El Nino’s Cold Tongue Baffles Climate Models


This post is prompted by an article published by Richard Seager et al. at AMS Journal Is There a Role for Human-Induced Climate Change in the Precipitation Decline that Drove the California Drought? Excerpts in italics with my bolds.

Overview

The recent California drought was associated with a persistent ridge at the west coast of North America that has been associated with, in part, forcing from warm SST anomalies in the tropical west Pacific. Here it is considered whether there is a role for human-induced climate change in favoring such a west coast ridge. The models from phase 5 of the Coupled Model Intercomparison Project do not support such a case either in terms of a shift in the mean circulation or in variance that would favor increased intensity or frequency of ridges. The models also do not support shifts toward a drier mean climate or more frequent or intense dry winters or to tropical SST states that would favor west coast ridges. However, reanalyses do show that over the last century there has been a trend toward circulation anomalies over the Pacific–North American domain akin to those during the height of the California drought.

Position of the Warm Pool in the western Pacific under La Niña conditions, and the convergence zone where the Warm Pool meets nutrient-enriched waters of the eastern equatorial Pacific. Tuna and their prey are most abundant in this convergence zone 21,48 (source: HadISST) 109 .

First we plot together the history of California winter precipitation and Arctic sea ice anomaly in terms of area covered by ice at the annual minimum month of September and also as the November through April winter average (Fig. 9, top). While all three are of course negative during the drought years there is no year to year relationship between these quantities. Next we composite 200-mb height anomalies, U.S. precipitation, and sea ice concentration for, during the period covered by sea ice data, the driest 15% of California winters and subtract the climatological winter values (Fig. 9, bottom). As in Seager et al. (2015), the composites show that when California is dry the entire western third of the United States tends to be dry and that there is a high pressure ridge located immediately off the west coast, which does not appear to be connected to a tropically sourced wave train. There also tends to be a trough over the North Atlantic, similar to winter 2013/14. There are notable localized sea ice concentration anomalies with increased ice in the Sea of Okohtsk, reduced ice in the Bering Sea, and increased ice in Hudson Bay and Labrador Sea, though the anomalies are small. These ice anomalies are consistent with atmospheric forcing. The Sea of Okhotsk and Hudson Bay/Labrador Sea anomalies appear under northerly flow that would favor cold advection and increased ice. The Bering Sea anomaly appears under easterly flow that would drive ice offshore. As shown by Seager et al. (2015), the dry California winters are also associated with North Pacific SST anomalies forced by the atmospheric wave train and the sea ice anomalies appear part of this feature rather than as causal drivers of the atmospheric circulation anomalies.

These analyses do not support the idea that variations in sea ice extent influence the prevalence of west coast ridges or dry winters in California.

Source: NASA

On the basis of the above analysis we conclude that the occurrence of persistent ridges at the west coast is more connected to SST anomalies than it is to sea ice anomalies. The CMIP5 model ensemble lends no support to the idea that ridge-inducing SST patterns become more likely as a result of rising GHGs. However, the models could be wrong so we next examine whether trends in observed SSTs lend any support to this idea. Trends were computed by straightforward linear least squares regression.

A number of features stand out in these trends regardless of the time period used.

  • Amid near-ubiquitous warming of the oceans the central equatorial Pacific stands out as a place that has not warmed.
  • The west–east SST gradient across the tropical Pacific has strengthened as the west Pacific has warmed.
  • Increased reanalysis precipitation over the Indian Ocean–Maritime Continent–tropical west Pacific and reduced reanalysis precipitation over the central equatorial Pacific Ocean were found.
  • Tropical geopotential heights have increased at all longitudes.
  • A trend toward a localized high pressure ridge extending from the subtropics toward Alaska across western North America.

These associations in the trends—a strengthened west–east SST gradient across the tropical Pacific and localized high pressure at the North American west coast—are in line with every piece of evidence based on observations and SST-forced models presented so far that there is a connection between drought-inducing circulation anomalies and tropical Pacific SSTs. The mediating influence is seen in the precipitation trends that show enhanced zonal gradients of tropical Indo-Pacific precipitation and a marked increase centered over the Maritime Continent region.

Conclusions and discussion

We have examined whether there is any evidence, observational and/or model based, that the precipitation decline that drove the California drought was contributed to by human-driven climate change. Findings are as follows:

  • The CMIP5 model ensemble provides no evidence for mean drying or increased prevalence of dry winters for California or a shift toward a west coast ridge either in the mean or as a more common event. They also provide no evidence of a shift in tropical SSTs toward a state with an increased west–east SST gradient that has been invoked as capable of forcing a west coast ridge and drought.
  • Analysis of observations-based reanalyses shows that west coast ridges, akin to that in winter 2013/14, are related to an increased west–east SST gradient across the tropical Pacific Ocean and have repeatedly occurred over past decades though as imperfect analogs.
  • SST-forced models can reproduce such ridges and their connection to tropical SST anomalies.  Century-plus-long reanalyses and SST-forced models indicate a long-term trend toward circulation anomalies more akin to that of winter 2013/14.
  • The trends of heights and SSTs in the reanalyses also show both an increased west–east SST gradient and a 200-mb ridge over western North America that, in terms of association between ocean and atmospheric circulation, matches those found via the other analyses on interannual time scales.
  • However, SST-forced models when provided the trends in SSTs create a 200-mb ridge over the central North Pacific and, in general, a circulation pattern that cannot be said to truly match that in reanalyses.

So can a case be made that human-driven climate change contributed to the precipitation drop that drives the drought? Not from the simulations of historical climate and projections of future climate of the CMIP5 multimodel ensemble.

These simulations show no current or future increase in the likelihood or extremity of negative precipitation, precipitation minus evaporation, west coast ridges, or ridge-forcing tropical SST patterns. However, when examining the observational record a case can be made that the climate system has been moving in a direction that favors both a ridge over the west coast, which has a limited similarity to that observed in winter 2013/14, the driest winter of the drought, and a ridge-generating pattern of increased west–east SST gradient across the tropical Pacific Ocean with warm SSTs in the Indo–west Pacific region. This observations-based argument then gets tripped up by SST-forced models, which know about the trends in SST but fail to simulate a trend toward a west coast ridge. On the other hand, idealized modeling indicates that preferential warming in the Indo–west Pacific region does generate a west coast ridge.

To make the argument we outline above requires rejecting the CMIP5 ensemble as a guide to how tropical climate responds to increased radiative forcing since this tropical ocean response is at odds with what they do. To do so follows in the footsteps of Kohyama and Hartmann (2017, p. 4248), who correctly point out that “El Niño–like mean-state warming is only a ‘majority decision’ based on currently available GCMs, most of which exhibit unrealistic nonlinearity of the ENSO dynamics” (see also Kohyama et al. 2017). The implications of changing tropical SST gradients would extend far beyond just California and include most regions of the world sensitive to ENSO-generated climate anomalies.

We believe that the current state of observational information, analysis of it, and climate modeling does not allow a confident rejection of the CMIP5 model responses and/or a confident assertion of human role in the precipitation drop of the California drought. We also believe that for the same reasons a human role cannot be excluded.

Comment:

The researchers set out to prove man-made global warming contributes to droughts in California, but their findings put them in a quandry.  The models include CO2 forcings, yet do not predict the conditions resulting in west coast droughts,   They have to admit the models are wrong in this respect (what else do the models get wrong?).  They cling to the hope that global warming can be tied to droughts, but have to admit there is no evidence from the failed models.

Postscript:

(a) Annual variation (Annual RMSE) of SST and Chl-a globally (units are °C/decade for SST and log(mg/m3/decade) for Chl-a). (b) The pattern of annual variation in the Bonney Upwelling, Southern Australia. (c) The pattern of annual variation in the the Florida Current, South East USA.

 

A separate study is Global patterns of change and variation in sea surface temperature and chlorophyll by Piers K. Dunstan et. al.

The blue tongue shows up as an equatorial pacific region that shows little variability over the 14 year period of study.  From the article:

The interaction between annual variation in SST and Chl-a provides insights into how and where linkages occur on annual time scales. Our analysis shows strong latitudinal bands associated with variation in seasonal warming (Fig. 4a). The equatorial Pacific, Indian and Atlantic Oceans are all characterised by very low annual RMSE for both SST and Chl-a. The mid latitudes of each ocean basin have higher variance in SST and/or Chl-a.

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Greenland Glaciers: History vs. Hysteria

The modern pattern of environmental scares started with Rachel Carson’s Silent Spring claiming chemical are killing birds, only today it is windmills doing the carnage. That was followed by ever expanding doomsday scenarios, from DDT, to SST, to CFC, and now the most glorious of them all, CO2. In all cases the menace was placed in remote areas difficult for objective observers to verify or contradict. From the wilderness bird sanctuaries, the scares are now hiding in the stratosphere and more recently in the Arctic and Antarctic polar deserts. See Progressively Scaring the World (Lewin book synopsis)

The advantage of course is that no one can challenge the claims with facts on the ground, or on the ice. Correction: Scratch “no one”, because the climate faithful are the exception. Highly motivated to go to the ends of the earth, they will look through their alarmist glasses and bring back the news that we are indeed doomed for using fossil fuels.

A recent example is a team of researchers from Dubai (the hot and sandy petro kingdom) going to Greenland to report on the melting of Helheim glacier there.  The article is NYUAD team finds reasons behind Greenland’s glacier melt.  Excerpts in italics with my bolds.

First the study and findings:

For the first time, warm waters that originate in the tropics have been found at uniform depth, displacing the cold polar water at the Helheim calving front, causing an unusually high melt rate. Typically, ocean waters near the terminus of an outlet glacier like Helheim are at the freezing point and cause little melting.

NYUAD researchers, led by Professor of Mathematics at NYU’s Courant Institute of Mathematical Sciences and Principal Investigator for NYU Abu Dhabi’s Centre for Sea Level Change David Holland, on August 5, deployed a helicopter-borne ocean temperature probe into a pond-like opening, created by warm ocean waters, in the usually thick and frozen melange in front of the glacier terminus.

Normally, warm, salty waters from the tropics travel north with the Gulf Stream, where at Greenland they meet with cold, fresh water coming from the polar region. Because the tropical waters are so salty, they normally sink beneath the polar waters. But Holland and his team discovered that the temperature of the ocean water at the base of the glacier was a uniform 4 degrees Centigrade from top to bottom at depth to 800 metres. The finding was also recently confirmed by Nasa’s OMG (Oceans Melting Greenland) project.

“This is unsustainable from the point of view of glacier mass balance as the warm waters are melting the glacier much faster than they can be replenished,” said Holland.

Surface melt drains through the ice sheet and flows under the glacier and into the ocean. Such fresh waters input at the calving front at depth have enormous buoyancy and want to reach the surface of the ocean at the calving front. In doing so, they draw the deep warm tropical water up to the surface, as well.

All around Greenland, at depth, warm tropical waters can be found at many locations. Their presence over time changes depending on the behaviour of the Gulf Stream. Over the last two decades, the warm tropical waters at depth have been found in abundance. Greenland outlet glaciers like Helheim have been melting rapidly and retreating since the arrival of these warm waters.

Then the Hysteria and Pledge of Alligence to Global Warming

“We are surprised to learn that increased surface glacier melt due to warming atmosphere can trigger increased ocean melting of the glacier,” added Holland. “Essentially, the warming air and warming ocean water are delivering a troubling ‘one-two punch’ that is rapidly accelerating glacier melt.”

My comment: Hold on.They studied effects from warmer ocean water gaining access underneath that glacier. Oceans have roughly 1000 times the heat capacity of the atmosphere, so the idea that the air is warming the water is far-fetched. And remember also that long wave radiation of the sort that CO2 can emit can not penetrate beyond the first millimeter or so of the water surface. So how did warmer ocean water get attributed to rising CO2? Don’t ask, don’t tell.  And the idea that air is melting Arctic glaciers is also unfounded.

Consider the basics of air parcels in the Arctic.

The central region of the Arctic is very dry. Why? Firstly because the water is frozen and releases very little water vapour into the atmosphere. And secondly because (according to the laws of physics) cold air can retain very little moisture.

Greenland has the only veritable polar ice cap in the Arctic, meaning that the climate is even harsher (10°C colder) than at the North Pole, except along the coast and in the southern part of the landmass where the Atlantic has a warming effect. The marked stability of Greenland’s climate is due to a layer of very cold air just above ground level, air that is always heavier than the upper layers of the troposphere. The result of this is a strong, gravity-driven air flow down the slopes (i.e. catabatic winds), generating gusts that can reach 200 kph at ground level.

Arctic air temperatures

Some history and scientific facts are needed to put these claims in context. Let’s start with what is known about Helheim Glacier.

Holocene history of the Helheim Glacier, southeast Greenland

Helheim Glacier ranks among the fastest flowing and most ice discharging outlets of the Greenland Ice Sheet (GrIS). After undergoing rapid speed-up in the early 2000s, understanding its long-term mass balance and dynamic has become increasingly important. Here, we present the first record of direct Holocene ice-marginal changes of the Helheim Glacier following the initial deglaciation. By analysing cores from lakes adjacent to the present ice margin, we pinpoint periods of advance and retreat. We target threshold lakes, which receive glacial meltwater only when the margin is at an advanced position, similar to the present. We show that, during the period from 10.5 to 9.6 cal ka BP, the extent of Helheim Glacier was similar to that of todays, after which it remained retracted for most of the Holocene until a re-advance caused it to reach its present extent at c. 0.3 cal ka BP, during the Little Ice Age (LIA). Thus, Helheim Glacier’s present extent is the largest since the last deglaciation, and its Holocene history shows that it is capable of recovering after several millennia of warming and retreat. Furthermore, the absence of advances beyond the present-day position during for example the 9.3 and 8.2 ka cold events as well as the early-Neoglacial suggest a substantial retreat during most of the Holocene.

Quaternary Science Reviews, Holocene history of the Helheim Glacier, southeast Greenland
A.A.Bjørk et. Al. 1 August 2018

The topography of Greenland shows why its ice cap has persisted for millenia despite its southerly location.  It is a bowl surrounded by ridges except for a few outlets, Helheim being a major one.

And then, what do we know about the recent history of glacier changes. Two Decades of Changes in Helheim Glacier

Helheim Glacier is the fastest flowing glacier along the eastern edge of Greenland Ice Sheet and one of the island’s largest ocean-terminating rivers of ice. Named after the Vikings’ world of the dead, Helheim has kept scientists on their toes for the past two decades. Between 2000 and 2005, Helheim quickly increased the rate at which it dumped ice to the sea, while also rapidly retreating inland- a behavior also seen in other glaciers around Greenland. Since then, the ice loss has slowed down and the glacier’s front has partially recovered, readvancing by about 2 miles of the more than 4 miles it had initially ­retreated.

NASA has compiled a time series of airborne observations of Helheim’s changes into a new visualization that illustrates the complexity of studying Earth’s changing ice sheets. NASA uses satellites and airborne sensors to track variations in polar ice year after year to figure out what’s driving these changes and what impact they will have in the future on global concerns like sea level rise.

Since 1997, NASA has collected data over Helheim Glacier almost every year during annual airborne surveys of the Greenland Ice Sheet using an airborne laser altimeter called the Airborne Topographic Mapper (ATM). Since 2009 these surveys have continued as part of Operation IceBridge, NASA’s ongoing airborne survey of polar ice and its longest-running airborne mission. ATM measures the elevation of the glacier along a swath as the plane files along the middle of the glacier. By comparing the changes in the height of the glacier surface from year to year, scientists estimate how much ice the glacier has lost.

The animation begins by showing the NASA P-3 plane collecting elevation data in 1998. The laser instrument maps the glacier’s surface in a circular scanning pattern, firing laser shots that reflect off the ice and are recorded by the laser’s detectors aboard the airplane. The instrument measures the time it takes for the laser pulses to travel down to the ice and back to the aircraft, enabling scientists to measure the height of the ice surface. In the animation, the laser data is combined with three-dimensional images created from IceBridge’s high-resolution camera system. The animation then switches to data collected in 2013, showing how the surface elevation and position of the calving front (the edge of the glacier, from where it sheds ice) have changed over those 15 years.

Helheim’s calving front retreated about 2.5 miles between 1998 and 2013. It also thinned by around 330 feet during that period, one of the fastest thinning rates in Greenland.

“The calving front of the glacier most likely was perched on a ledge in the bedrock in 1998 and then something altered its equilibrium,” said Joe MacGregor, IceBridge deputy project scientist. “One of the most likely culprits is a change in ocean circulation or temperature, such that slightly warmer water entered into the fjord, melted a bit more ice and disturbed the glacier’s delicate balance of forces.”

Comment:

Once again, history is a better guide than hysteria.  Over time glaciers advance and retreat, and incursions of warm water are a key factor.  Greenland ice cap and glaciers are part of the the Arctic self-oscillating climate system operating on a quasi-60 year cycle.

H2O Reduces CO2 Climate Sensitivity

Francis Massen writes at his blog meteoLCD on The Kauppinen papers, summarizing and linking to studies by Dr Jyrki Kauppinen (Turku University in Finland) regarding the climate sensitivity problem. Excerpts in italics with my bolds

Dr. Jyrki Kauppinen (et al.) has published during the last decade several papers on the problem of finding the climate sensitivity (List with links at end). All these papers are, at least for big parts, heavy on mathematics, even if parts thereof are not too difficult to grasp. Let me try to summarize in layman’s words (if possible):

The authors remember that the IPCC models trying to deliver an estimate for ECS or TCR usually take the relative humidity of the atmosphere as constant, and practically restrict to allowing one major cause leading to a global temperature change: the change of the radiative forcing Q. Many factors can change Q, but overall the IPCC estimates the human caused emission of greenhouse gases and the land usage changes (like deforestation) are the principal causes of a changing Q. If the climate sensitivy is called R, the IPCC assumes that DT = R*DQ (here “D” is taken as the greek capital “delta”). This assumption leads to a positive water vapour feedback factor and so to the high values of R.

Kauppinen et al. disagree: They write that one has to include in the expression of DT the changes of the atmospheric water mass (which may show up in changes of the relative humidity and/or low cloud cover. Putting this into a equation leads to the conclusion that the water vapour feedback is negative and as a consequence that climate sensitivity is much lower.

Let us insist that the authors do not write that increasing CO2 concentrations do not have any influence on global temperature. They have, but it is many times smaller than the influence of the hydrological cycle.

Here what Kauppinen et al. find if they take real observational values (no fudge parameters!) and compare their calculated result to one of the offical global temperature series:

Figure 4. [2] Observed global mean temperature anomaly (red), calculated anomaly (blue), which is the sum of the natural and carbon dioxide contributions. The green line is the CO2 contribution merely. The natural component is derived using the observed changes in the relative humidity. The time resolution is one year.

The visual correlation is quite good: the changes in low cloud cover explain almost completely the warming of the last 40 years!

In their 2017 paper, they conclude to a CO2 sensitivity of 0.24°C (about ten times lower than the IPCC consensus value). In the last 2019 paper they refine their estimate, find again R=0.24 and give the following figure:

Figure 2. [2] Global temperature anomaly (red) and the global low cloud cover changes (blue) according to the observations. The anomalies are between summer 1983 and summer 2008. The time resolution of the data is one month, but the seasonal signal is removed. Zero corresponds about 15°C for the temperature and 26 % for the low cloud cover.

Clearly the results are quite satisfactory, and show also clearly that their simple model can not render the spikes caused by volcanic or El Nino activity, as these natural disturbances are not included in their balance.

The authors conclude that the IPCC models can not give a “correct” value for the climate sensitivity, as they practically ignore (at least until AR5) the influence of low cloud cover. Their finding is politically explosive in the sense that there is no need for a precipitous decarbonization (even if on the longer run a reduction in carbon intensity in many activities might be recommendable.

Francis Massen opinion

As written in part 1, Kauppinen et al. are not the first to conclude to a much lower climate sensitivity as the IPCC and its derived policies do. Many papers, even if based on different assumptions and methods come to a similar conclusion i.e. the IPCC models give values that are (much) too high. Kaupinnen et al. also show that the hydrological cycle can not be ignored, and that the influence of low clouds cover (possibly modulated by solar activity) should not be ignored.

What makes their papers so interesting is that they rely only on practically 2 observational factors and are not forced to introduce various fudge parameters.

The whole problem is a complicated one, and rushing into ill-reflected and painful policies should be avoided before we have a much clearer picture.

Footnote: The four Kauppinen papers.

2011 : Major portions in climate change: physical approach. (International Review of Physics) link

2014: Influence of relative humidity and clouds on the global mean surface temperature (Energy & Environment). Link to abstract.   Link to jstor read-only version (download is paywalled).

2018: Major feedback factors and effects of the cloud cover and the relative humidity on the climate. Link.

2019: No experimental evidence for the significant anthropogenic climate change. Link.
The last two papers are on arXiv and are not peer reviewed, not an argument to refute them in my opinion.

Francis Massen (francis.massen@education.lu), a physicist by education, who manages and operates the meteo/climate station http://meteo.lcd.lu of the Lycée Classique de Diekirch in Luxembourg, Europe.

See Also my recent post More 2019 Evidence of Nature’s Sunscreen

Postscript:

Dr. Dai Davies summarized this perspective this way:

The most fundamental of the many fatal mathematical flaws in the IPCC related modelling of atmospheric energy dynamics is to start with the impact of CO2 and assume water vapour as a dependent ‘forcing’ .  This has the tail trying to wag the dog. The impact of CO2 should be treated as a perturbation of the water cycle. When this is done, its effect is negligible.

See Davies article synopsis at Earth Climate Layers

Update: The LIA Warming Rebound Is Over

Figure 1. Graph showing the number of volcanoes reported to have been active each year since 1800 CE. Total number of volcanoes with reported eruptions per year (thin upper black line) and 10-year running mean of same data (thick upper red line). Lower lines show only the annual number of volcanoes producing large eruptions (>= 0.1 km3 of tephra or magma) and scale is enlarged on the right axis; thick red lower line again shows 10-year running mean. Global Volcanism Project Discussion

Update August 2, 2019

University of Bern confirms in a recent announcement that volcanoes triggered the depths of the LIA (Little Ice Age).  Their article is Volcanoes shaped the climate before humankind. H/T GWPF.  However, they spin the story in support of climate alarm (emergency, whatever), rather than making the more obvious point that recent warming was  recovering to roughly Medieval Warming levels after the abnormal cooling disruption from volcanoes. Excerpt in italics with my bolds.

“The new Bern study not only explains the global early 19th century climate, but it is also relevant for the present. “Given the large climatic changes seen in the early 19th century, it is difficult to define a pre-industrial climate,” explains lead author Stefan Brönnimann, “a notion to which all our climate targets refer.” And this has consequences for the climate targets set by policymakers, who want to limit global temperature increases to between 1.5 and 2 degrees Celsius at the most. Depending on the reference period, the climate has already warmed up much more significantly than assumed in climate discussions. The reason: Today’s climate is usually compared with a 1850-1900 reference period to quantify current warming. Seen in this light, the average global temperature has increased by 1 degree. “1850 to 1900 is certainly a good choice but compared to the first half of the 19th century, when it was significantly cooler due to frequent volcanic eruptions, the temperature increase is already around 1.2 degrees,” Stefan Brönnimann points out.”

Bern seems preoccupied with targets and accounting, while others are concerned to understand the role of volcanoes in natural climate change.  A previous post gives a more detailed explanation, thanks to a suggestion I received.

The LIA Warming Rebound Is Over

Thanks to Dr. Francis Manns for drawing my attention to the role of Volcanoes as a climate factor, particularly related to the onset of the Little Ice Age (LIA), 1400 to 1900 AD. I was aware that the temperature record since about 1850 can be explained by a steady rise of 0.5C per century rebound overlaid with a quasi-60 year cycle, most likely oceanic driven. See below Dr. Syun Akasofu 2009 diagram from his paper Two Natural Components of Recent Warming.
When I presented this diagram to my warmist friends, they would respond, “But you don’t know what caused the LIA or what ended it!” To which I would say, “True, but we know it wasn’t due to burning fossil fuels.” Now I find there is a body of evidence suggesting what caused the LIA and why the temperature rebound may be over. Part of it is a familiar observation that the LIA coincided with a period when the sun was lacking sunspots, the Maunder Minimum, and later the Dalton.

Not to be overlooked is the climatic role of volcano activity inducing deep cooling patterns such as the LIA.  Jihong Cole-Dai explains in a paper published 2010 entitled Volcanoes and climate. Excerpt in italics with my bolds.

There has been strong interest in the role of volcanism during the climatic episodes of Medieval Warm Period (MWP,800–1200 AD) and Little Ice Age (LIA, 1400–1900AD), when direct human influence on the climate was negligible. Several studies attempted to determine the influence of solar forcing and volcanic forcing and came to different conclusions: Crowley and colleagues suggested that increased frequency of stratospheric eruptions in the seventeenth century and again in the early nineteenth century was responsible in large part for LIA. Shindell et al. concluded that LIA is the result of reduced solar irradiance, as seen in the Maunder Minimum of sunspots, during the time period. Ice core records show that the number of large volcanic eruptions between 800 and 1100 AD is possibly small (Figure 1), when compared with the eruption frequency during LIA. Several researchers have proposed that more frequent large eruptions during the thirteenth century(Figure 1) contributed to the climatic transition from MWP to LIA, perhaps as a part of the global shift from a warmer to a colder climate regime. This suggests that the volcanic impact may be particularly significant during periods of climatic transitions.

How volcanoes impact on the atmosphere and climate

Alan Robock explains Climatic Impacts of Volcanic Eruptions in Chapter 53 of the Encyclopedia of Volcanoes.  Excerpts in italics with my bolds.

The major component of volcanic eruptions is the matter that emerges as solid, lithic material or solidifies into large particles, which are referred to as ash or tephra. These particles fall out of the atmosphere very rapidly, on timescales of minutes to a few days, and thus have no climatic impacts but are of great interest to volcanologists, as seen in the rest of this encyclopedia. When an eruption column still laden with these hot particles descends down the slopes of a volcano, this pyroclastic flow can be deadly to those unlucky enough to be at the base of the volcano. The destruction of Pompeii and Herculaneum after the AD 79 Vesuvius eruption is the most famous example.

Volcanic eruptions typically also emit gases, with H2O, N2, and CO2 being the most abundant. Over the lifetime of the Earth, these gases have been the main source of the Earth’s atmosphere and ocean after the primitive atmosphere of hydrogen and helium was lost to space. The water has condensed into the oceans, the CO2 has been changed by plants into O2 or formed carbonates, which sink to the ocean bottom, and some of the C has turned into fossil fuels. Of course, we eat plants and animals, which eat the plants, we drink the water, and we breathe the oxygen, so each of us is made of volcanic emissions. The atmosphere is now mainly composed of N2 (78%) and O2 (21%), both of which had sources in volcanic emissions.

Of these abundant gases, both H2O and CO2 are important greenhouse gases, but their atmospheric concentrations are so large (even for CO2 at only 400 ppm in 2013) that individual eruptions have a negligible effect on their concentrations and do not directly impact the greenhouse effect. Global annually averaged emissions of CO2 from volcanic eruptions since 1750 have been at least 100 times smaller than those from human activities. Rather the most important climatic effect of explosive volcanic eruptions is through their emission of sulfur species to the stratosphere, mainly in the form of SO2, but possibly sometimes as H2S. These sulfur species react with H2O to form H2SO4 on a timescale of weeks, and the resulting sulfate aerosols produce the dominant radiative effect from volcanic eruptions.

The major effect of a volcanic eruption on the climate system is the effect of the stratospheric cloud on solar radiation (Figure 53.1). Some of the radiation is scattered back to space, increasing the planetary albedo and cooling the Earth’s atmosphere system. The sulfate aerosol particles (typical effective radius of 0.5 mm, about the same size as the wavelength of visible light) also forward scatter much of the solar radiation, reducing the direct solar beam but increasing the brightness of the sky. After the 1991 Pinatubo eruption, the sky around the sun appeared more white than blue because of this. After the El Chicho´n eruption of 1982 and the Pinatubo eruption of 1991, the direct radiation was significantly reduced, but the diffuse radiation was enhanced by almost as much. Nevertheless, the volcanic aerosol clouds reduced the total radiation received at the surface.

Crowley et al 2008 go into the details in their paper Volcanism and the Little Ice Age. Excerpts in italics with my bolds.

Although solar variability has often been considered the primary agent for LIA cooling, the most comprehensive test of this explanation (Hegerl et al., 2003) points instead to volcanism being substantially more important, explaining as much as 40% of the decadal-scale variance during the LIA. Yet, one problem that has continually plagued climate researchers is that the paleo-volcanic record, reconstructed from Antarctic and Greenland ice cores, cannot be well calibrated against the instrumental record. This is because the primary instrumental volcano reconstruction used by the climate community is that of Sato et al. (1993), which is relatively poorly constrained by observations prior to 1960 (especially in the southern hemisphere).

Here, we report on a new study that has successfully calibrated the Antarctic sulfate record of volcanism from the 1991 eruptions of Pinatubo (Philippines) and Hudson (Chile) against satellite aerosol optical depth (AOD) data (AOD is a measure of stratospheric transparency to incoming solar radiation). A total of 22 cores yield an area-weighted sulfate accumulation rate of 10.5 kg/km2 , which translates into a conversion rate for AOD of 0.011 AOD/ kg/km2 sulfate. We validated our time series by comparing a canonical growth and decay curve for eruptions for Krakatau (1883), the 1902 Caribbean eruptions (primarily Santa Maria), and the 1912 eruption of Novarupta/Katmai (Alaska)

We therefore applied the methodology to part of the LIA record that had some of the largest temperature changes over the last millennium.

Figure 2: Comparison of 30-90°N version of ice core reconstruction with Jones et al. (1998) temperature reconstruction over the interval 1630-1850. Vertical dashed lines denote levels of coincidence between eruptions and reconstructed cooling. AOD = Aerosol Optical Depth.

The ice core chronology of volcanoes is completely independent of the (primarily) tree ring based temperature reconstruction. The volcano reconstruction is deemed accurate to within 0 ± 1 years over this interval. There is a striking agreement between 16 eruptions and cooling events over the interval 1630-1850. Of particular note is the very large cooling in 1641-1642, due to the concatenation of sulfate plumes from two eruptions (one in Japan and one in the Philippines), and a string of eruptions starting in 1667 and culminating in a large tropical eruption in 1694 (tentatively attributed to Long Island, off New Guinea). This large tropical eruption (inferred from ice core sulfate peaks in both hemispheres) occurred almost exactly at the beginning of the coldest phase of the LIA in Europe and represents a strong argument against the implicit link of Late Maunder Minimum (1640-1710) cooling to solar irradiance changes.

Figure 1: Comparison of new ice core reconstruction with various instrumental-based reconstructions of stratospheric aerosol forcing. The asterisks refer to some modification to the instrumental data; for Sato et al. (1993) and the Lunar AOD, the asterisk refers to the background AOD being removed for the last 40 years. For Stothers (1996), it refers to the fact that instrumental observations for Krakatau (1883) and the 1902 Caribbean eruptions were only for the northern hemisphere. To obtain a global AOD for these estimates we used Stothers (1996) data for the northern hemisphere and our data for the southern hemisphere. The reconstruction for Agung eruption (1963) employed Stothers (1996) results from 90°N-30°S and the Antarctic ice core data for 30-90°S.

During the 18th century lull in eruptions, temperatures recovered somewhat but then cooled early in the 19th century. The sequence begins with a newly postulated unknown tropical eruption in midlate 1804, which deposited sulfate in both Greenland and Antarctica. Then, there are four well-documented eruptions—an unknown tropical eruption in 1809, Tambora (1815) and a second doublet tentatively attributed in part to Babuyan (Philippines) in 1831 and Cosiguina (Nicaragua) in 1835. These closely spaced eruptions are not only large but have a temporally extended effect on climate, due to the fact that they reoccur within the 10-year recovery timescale of the ocean mixed layer.

The ocean has not recovered from the first eruption so the second eruption drives the temperatures to an even lower state.

Implications for Contemporary Climate Science

In this context Dr. Francis Manns went looking for a volcanic signature in recent temperature records. His paper is Volcano and Enso Punctuation of North American Temperature: Regression Toward the Mean  Excerpts in italics with my bolds.

Abstract: Contrary to popular media and urban mythology the global warming we have experienced since the Little Ice Age is likely finished. A review of 10 temperature time series from US cities ranging from the hottest in Death Valley, CA, to possible the most isolated and remote at Key West, FL, show rebound from the Little Ice Age (which ended in the Alps by 1840) by 1870. The United States reached temperatures like modern temperatures (1950 – 2000) by about 1870, then declined precipitously principally caused by Krakatoa, and a series of other violent eruptions. Nine of these time series started when instrumental measurement was in its infancy and the world was cooled by volcanic dust and sulphate spewed into the atmosphere and distributed by the jet streams. These ten cities represent a sample of the millions of temperature measurements used in climate models. The average annual temperatures are useful because they account for seasonal fluctuations. In addition, time series from these cities are punctuated by El Nino Southern Oscillation (ENSO).

As should be expected, temperature at each city reacted differently to differing events. Several cities measured the effects of Krakatoa in 1883 while only Death Valley, CA and Berkeley CA sensed the minor new volcano Paricutin in Michoacán, Mexico. The Key West time series shows rapid rebound from the Little Ice Age as do Albany, NY, Harrisburg, PA, and Chicago. IL long before the petroleum-industrial revolution got into full swing. Recording at most sites started during a volcanic induced temperature minimum thus giving an impression of global warming to which industrial carbon dioxide is persuasively held responsible. Carbon dioxide, however, cannot be proven responsible for these temperatures. These and likely subsequent temperatures could be the result of regression to the normal equilibrium temperatures of the earth (for now). If one were to remove the volcanic punctuation and El Nino Southern Oscillation (ENSO) input many would display very little alarming warming from 1815 to 2000. This review illustrates the weakness of linear regression as a measure of change. If there is a systemic reason for the global warming hypothesis, it is an anthropogenic error in both origin and termination. ENSO compliments and confirms the validity of NOAA temperature data. Temperatures since 2000 during the current hiatus are not available because NOAA has closed the public website.

Example of time series from Manns. Numbers refer to major named volcano eruptions listed in his paper.  For instance, #3 was Krakatoa

The cooling effect is said to have lasted for 5 years after Krakatoa erupted – from 1883 to 1888. Examination of these charts, However, shows that, e.g., Krakatoa did not add to the cooling effect from earlier eruptions of Cosaguina in 1835 and Askja in 1875. The temperature charts all show rapid rebound to equilibrium temperature for the region affected in a year or two at most.

Manns Map

Fourteen major volcanic eruptions, however, were recorded between 1883 and 1918 (Robock, 2000, and this essay). Some erupted for days or weeks and some were cataclysmic and shorter. The sum of all these eruptions from Krakatoa onward effected temperatures early in the instrumental age. Judging from wasting glaciers in the Alps, abrupt retreat began about 1860).

Manns Conclusions:
1)Four of these time series (Albany, Harrisburg, Chicago and Key West) show recovery to the range of today’s temperatures by 1870 before the eruption of Askja in 1875. The temperature rebounded very quickly after the Little Ice Age in the northern hemisphere.

Manns ENSO Map

2)Volcanic eruptions and unrelated huge swings shown from ENSO largely rule global temperature. Volcanic history and the El Nino Southern Oscillation (ENSO) trump all other increments of temperature that may be hidden in the lists.

3)The sum of the eruptions from Krakatoa (1883) to Katla (1918) and Cerro Azul (1932) was a cold start for climate models.

4)It is beyond doubt that academic and bureau climate models use data that was gathered when volcanic activity had depressed global temperature. The cluster from Krakatoa to Katla (1883 -1918) were global.

5)Modern events, Mount Saint Helens and Pinatubo, moreover, were a fraction of the event intensity of the late 19th and early 20th centuries eruptions.

6) The demise of frequent violent volcanos has allowed the planet to regress toward a norm (for now).

Summary

These findings describe a natural process by which a series of volcanoes along with a period of quiet solar cycles ended the Medieval Warm Period (MWP), chilling the land and inducing deep oceanic cooling resulting in the Little Ice Age. With much less violent volcanic activity in the 20th century, coincidental with typically active solar cycles, a Modern Warm Period ensued with temperatures rebounding back to approximately the same as before the LIA.

This suggests that humans and the biosphere were enhanced by a warming process that has ended. The solar cycles are again going quiet and are forecast to continue that way. Presently, volcanic activity has been routine, showing no increase over the last 100 years. No one knows how long will last the current warm period, a benefit to us from the ocean recovering after the LIA. But future periods are as likely to be cooler than to be warmer compared to the present.

Greenland Makes Its Own Weather

This is a reblog from Ontario-Goldfish entitled Greenland blocks the warm air Excerpts in italics with my bolds.

All the doom-mongers said that Greenland would melt from the Europe stagnant air. Ha! This demonstrates interesting physics.

The warm air just bounces off Greenland. This shows the permanent high pressure air over the ice, and shows the winds.

And the ice stays as cold as ever. I never realized it before, but this demonstrates my concept of an ‘ice block’, which is a major component of my hypothesis for major ice advances. No need for solar cycles.

The glacier creates its own weather. That comes mainly from the ability to shed off solar heat flux, and to maintain a high pressure zone. This seems to only happen for continental ice sheets, the Arctic ocean has its own problems with the sea trying to melt it from below, so it isn’t cold enough for weather-making.

Thus, once a continental ice sheet starts (or the Arctic ice becomes very thick), then it’s a ‘snowball’ effect. The true Ice Age starts. But, as I have said, there is the little problem of the continents sinking under ice load, so we won’t have this for another few thousand years.

All the papers that reported this doom won’t follow through. People will be left with the impression that Greenland is melting, and impressions are what the warmies live on.

 

The LIA Warming Rebound Is Over

Figure 1. Graph showing the number of volcanoes reported to have been active each year since 1800 CE. Total number of volcanoes with reported eruptions per year (thin upper black line) and 10-year running mean of same data (thick upper red line). Lower lines show only the annual number of volcanoes producing large eruptions (>= 0.1 km3 of tephra or magma) and scale is enlarged on the right axis; thick red lower line again shows 10-year running mean. Global Volcanism Project Discussion

Thanks to Dr. Francis Manns for drawing my attention to the role of Volcanoes as a climate factor, particularly related to the onset of the Little Ice Age (LIA), 1400 to 1900 AD. I was aware that the temperature record since about 1850 can be explained by a steady rise of 0.5C per century rebound overlaid with a quasi-60 year cycle, most likely oceanic driven. See below Dr. Syun Akasofu 2009 diagram from his paper Two Natural Components of Recent Warming.
When I presented this diagram to my warmist friends, they would respond, “But you don’t know what caused the LIA or what ended it!” To which I would say, “True, but we know it wasn’t due to burning fossil fuels.” Now I find there is a body of evidence suggesting what caused the LIA and why the temperature rebound may be over. Part of it is a familiar observation that the LIA coincided with a period when the sun was lacking sunspots, the Maunder Minimum.

Not to be overlooked is the climatic role of volcano activity inducing deep cooling patterns such as the LIA.  Jihong Cole-Dai explains in a paper published 2010 entitled Volcanoes and climate. Excerpt in italics with my bolds.

There has been strong interest in the role of volcanism during the climatic episodes of Medieval Warm Period (MWP,800–1200 AD) and Little Ice Age (LIA, 1400–1900AD), when direct human influence on the climate was negligible. Several studies attempted to determine the influence of solar forcing and volcanic forcing and came to different conclusions: Crowley and colleagues suggested that increased frequency of stratospheric eruptions in the seventeenth century and again in the early nineteenth century was responsible in large part for LIA. Shindell et al. concluded that LIA is the result of reduced solar irradiance, as seen in the Maunder Minimum of sunspots, during the time period. Ice core records show that the number of large volcanic eruptions between 800 and 1100 AD is possibly small (Figure 1), when compared with the eruption frequency during LIA. Several researchers have proposed that more frequent large eruptions during the thirteenth century(Figure 1) contributed to the climatic transition from MWP to LIA, perhaps as a part of the global shift from a warmer to a colder climate regime. This suggests that the volcanic impact may be particularly significant during periods of climatic transitions.

How volcanoes impact on the atmosphere and climate

Alan Robock explains Climatic Impacts of Volcanic Eruptions in Chapter 53 of the Encyclopedia of Volcanoes.  Excerpts in italics with my bolds.

The major component of volcanic eruptions is the matter that emerges as solid, lithic material or solidifies into large particles, which are referred to as ash or tephra. These particles fall out of the atmosphere very rapidly, on timescales of minutes to a few days, and thus have no climatic impacts but are of great interest to volcanologists, as seen in the rest of this encyclopedia. When an eruption column still laden with these hot particles descends down the slopes of a volcano, this pyroclastic flow can be deadly to those unlucky enough to be at the base of the volcano. The destruction of Pompeii and Herculaneum after the AD 79 Vesuvius eruption is the most famous example.

Volcanic eruptions typically also emit gases, with H2O, N2, and CO2 being the most abundant. Over the lifetime of the Earth, these gases have been the main source of the Earth’s atmosphere and ocean after the primitive atmosphere of hydrogen and helium was lost to space. The water has condensed into the oceans, the CO2 has been changed by plants into O2 or formed carbonates, which sink to the ocean bottom, and some of the C has turned into fossil fuels. Of course, we eat plants and animals, which eat the plants, we drink the water, and we breathe the oxygen, so each of us is made of volcanic emissions. The atmosphere is now mainly composed of N2 (78%) and O2 (21%), both of which had sources in volcanic emissions.

Of these abundant gases, both H2O and CO2 are important greenhouse gases, but their atmospheric concentrations are so large (even for CO2 at only 400 ppm in 2013) that individual eruptions have a negligible effect on their concentrations and do not directly impact the greenhouse effect. Global annually averaged emissions of CO2 from volcanic eruptions since 1750 have been at least 100 times smaller than those from human activities. Rather the most important climatic effect of explosive volcanic eruptions is through their emission of sulfur species to the stratosphere, mainly in the form of SO2, but possibly sometimes as H2S. These sulfur species react with H2O to form H2SO4 on a timescale of weeks, and the resulting sulfate aerosols produce the dominant radiative effect from volcanic eruptions.

The major effect of a volcanic eruption on the climate system is the effect of the stratospheric cloud on solar radiation (Figure 53.1). Some of the radiation is scattered back to space, increasing the planetary albedo and cooling the Earth’s atmosphere system. The sulfate aerosol particles (typical effective radius of 0.5 mm, about the same size as the wavelength of visible light) also forward scatter much of the solar radiation, reducing the direct solar beam but increasing the brightness of the sky. After the 1991 Pinatubo eruption, the sky around the sun appeared more white than blue because of this. After the El Chicho´n eruption of 1982 and the Pinatubo eruption of 1991, the direct radiation was significantly reduced, but the diffuse radiation was enhanced by almost as much. Nevertheless, the volcanic aerosol clouds reduced the total radiation received at the surface.

Crowley et al 2008 go into the details in their paper Volcanism and the Little Ice Age. Excerpts in italics with my bolds.

Although solar variability has often been considered the primary agent for LIA cooling, the most comprehensive test of this explanation (Hegerl et al., 2003) points instead to volcanism being substantially more important, explaining as much as 40% of the decadal-scale variance during the LIA. Yet, one problem that has continually plagued climate researchers is that the paleo-volcanic record, reconstructed from Antarctic and Greenland ice cores, cannot be well calibrated against the instrumental record. This is because the primary instrumental volcano reconstruction used by the climate community is that of Sato et al. (1993), which is relatively poorly constrained by observations prior to 1960 (especially in the southern hemisphere).

Here, we report on a new study that has successfully calibrated the Antarctic sulfate record of volcanism from the 1991 eruptions of Pinatubo (Philippines) and Hudson (Chile) against satellite aerosol optical depth (AOD) data (AOD is a measure of stratospheric transparency to incoming solar radiation). A total of 22 cores yield an area-weighted sulfate accumulation rate of 10.5 kg/km2 , which translates into a conversion rate for AOD of 0.011 AOD/ kg/km2 sulfate. We validated our time series by comparing a canonical growth and decay curve for eruptions for Krakatau (1883), the 1902 Caribbean eruptions (primarily Santa Maria), and the 1912 eruption of Novarupta/Katmai (Alaska)

We therefore applied the methodology to part of the LIA record that had some of the largest temperature changes over the last millennium.

Figure 2: Comparison of 30-90°N version of ice core reconstruction with Jones et al. (1998) temperature reconstruction over the interval 1630-1850. Vertical dashed lines denote levels of coincidence between eruptions and reconstructed cooling. AOD = Aerosol Optical Depth.

The ice core chronology of volcanoes is completely independent of the (primarily) tree ring based temperature reconstruction. The volcano reconstruction is deemed accurate to within 0 ± 1 years over this interval. There is a striking agreement between 16 eruptions and cooling events over the interval 1630-1850. Of particular note is the very large cooling in 1641-1642, due to the concatenation of sulfate plumes from two eruptions (one in Japan and one in the Philippines), and a string of eruptions starting in 1667 and culminating in a large tropical eruption in 1694 (tentatively attributed to Long Island, off New Guinea). This large tropical eruption (inferred from ice core sulfate peaks in both hemispheres) occurred almost exactly at the beginning of the coldest phase of the LIA in Europe and represents a strong argument against the implicit link of Late Maunder Minimum (1640-1710) cooling to solar irradiance changes.

Figure 1: Comparison of new ice core reconstruction with various instrumental-based reconstructions of stratospheric aerosol forcing. The asterisks refer to some modification to the instrumental data; for Sato et al. (1993) and the Lunar AOD, the asterisk refers to the background AOD being removed for the last 40 years. For Stothers (1996), it refers to the fact that instrumental observations for Krakatau (1883) and the 1902 Caribbean eruptions were only for the northern hemisphere. To obtain a global AOD for these estimates we used Stothers (1996) data for the northern hemisphere and our data for the southern hemisphere. The reconstruction for Agung eruption (1963) employed Stothers (1996) results from 90°N-30°S and the Antarctic ice core data for 30-90°S.

During the 18th century lull in eruptions, temperatures recovered somewhat but then cooled early in the 19th century. The sequence begins with a newly postulated unknown tropical eruption in midlate 1804, which deposited sulfate in both Greenland and Antarctica. Then, there are four well-documented eruptions—an unknown tropical eruption in 1809, Tambora (1815) and a second doublet tentatively attributed in part to Babuyan (Philippines) in 1831 and Cosiguina (Nicaragua) in 1835. These closely spaced eruptions are not only large but have a temporally extended effect on climate, due to the fact that they reoccur within the 10-year recovery timescale of the ocean mixed layer.

The ocean has not recovered from the first eruption so the second eruption drives the temperatures to an even lower state.

Implications for Contemporary Climate Science

In this context Dr. Francis Manns went looking for a volcanic signature in recent temperature records. His paper is Volcano and Enso Punctuation of North American Temperature: Regression Toward the Mean  Excerpts in italics with my bolds.

Abstract: Contrary to popular media and urban mythology the global warming we have experienced since the Little Ice Age is likely finished. A review of 10 temperature time series from US cities ranging from the hottest in Death Valley, CA, to possible the most isolated and remote at Key West, FL, show rebound from the Little Ice Age (which ended in the Alps by 1840) by 1870. The United States reached temperatures like modern temperatures (1950 – 2000) by about 1870, then declined precipitously principally caused by Krakatoa, and a series of other violent eruptions. Nine of these time series started when instrumental measurement was in its infancy and the world was cooled by volcanic dust and sulphate spewed into the atmosphere and distributed by the jet streams. These ten cities represent a sample of the millions of temperature measurements used in climate models. The average annual temperatures are useful because they account for seasonal fluctuations. In addition, time series from these cities are punctuated by El Nino Southern Oscillation (ENSO).

As should be expected, temperature at each city reacted differently to differing events. Several cities measured the effects of Krakatoa in 1883 while only Death Valley, CA and Berkeley CA sensed the minor new volcano Paricutin in Michoacán, Mexico. The Key West time series shows rapid rebound from the Little Ice Age as do Albany, NY, Harrisburg, PA, and Chicago. IL long before the petroleum-industrial revolution got into full swing. Recording at most sites started during a volcanic induced temperature minimum thus giving an impression of global warming to which industrial carbon dioxide is persuasively held responsible. Carbon dioxide, however, cannot be proven responsible for these temperatures. These and likely subsequent temperatures could be the result of regression to the normal equilibrium temperatures of the earth (for now). If one were to remove the volcanic punctuation and El Nino Southern Oscillation (ENSO) input many would display very little alarming warming from 1815 to 2000. This review illustrates the weakness of linear regression as a measure of change. If there is a systemic reason for the global warming hypothesis, it is an anthropogenic error in both origin and termination. ENSO compliments and confirms the validity of NOAA temperature data. Temperatures since 2000 during the current hiatus are not available because NOAA has closed the public website.

Example of time series from Manns. Numbers refer to major named volcano eruptions listed in his paper.  For instance, #3 was Krakatoa

The cooling effect is said to have lasted for 5 years after Krakatoa erupted – from 1883 to 1888. Examination of these charts, However, shows that, e.g., Krakatoa did not add to the cooling effect from earlier eruptions of Cosaguina in 1835 and Askja in 1875. The temperature charts all show rapid rebound to equilibrium temperature for the region affected in a year or two at most.

Manns Map

Fourteen major volcanic eruptions, however, were recorded between 1883 and 1918 (Robock, 2000, and this essay). Some erupted for days or weeks and some were cataclysmic and shorter. The sum of all these eruptions from Krakatoa onward effected temperatures early in the instrumental age. Judging from wasting glaciers in the Alps, abrupt retreat began about 1860).

Manns Conclusions:
1)Four of these time series (Albany, Harrisburg, Chicago and Key West) show recovery to the range of today’s temperatures by 1870 before the eruption of Askja in 1875. The temperature rebounded very quickly after the Little Ice Age in the northern hemisphere.

Manns ENSO Map

2)Volcanic eruptions and unrelated huge swings shown from ENSO largely rule global temperature. Volcanic history and the El Nino Southern Oscillation (ENSO) trump all other increments of temperature that may be hidden in the lists.

3)The sum of the eruptions from Krakatoa (1883) to Katla (1918) and Cerro Azul (1932) was a cold start for climate models.

4)It is beyond doubt that academic and bureau climate models use data that was gathered when volcanic activity had depressed global temperature. The cluster from Krakatoa to Katla (1883 -1918) were global.

5)Modern events, Mount Saint Helens and Pinatubo, moreover, were a fraction of the event intensity of the late 19th and early 20th centuries eruptions.

6) The demise of frequent violent volcanos has allowed the planet to regress toward a norm (for now).

Summary

These findings describe a natural process by which a series of volcanoes along with a period of quiet solar cycles ended the Medieval Warm Period (MWP), chilling the land and inducing deep oceanic cooling resulting in the Little Ice Age. With much less violent volcanic activity in the 20th century, coincidental with typically active solar cycles, a Modern Warm Period ensued with temperatures rebounding back to approximately the same as before the LIA.

This suggests that humans and the biosphere were enhanced by a warming process that has ended. The solar cycles are again going quiet and are forecast to continue that way. Presently, volcanic activity has been routine, showing no increase over the last 100 years. No one knows how long will last the current warm period, a benefit to us from the ocean recovering after the LIA. But future periods are as likely to be cooler than to be warmer compared to the present.

Climate Changes Both Ways

The title comes from a news event last week when President Trump reminded Prince Charles of a natural truism:  Climate change goes both ways.  A media freak out ensued, as shown by this example from Newsweek.  Excerpt in italics with my bolds.

President Donald Trump said Wednesday he believes there has been a change in the weather due to climate change, but that “it changes both ways.”

The president then explained his views on the climate. “Don’t forget, it used to be called global warming, that wasn’t working, then it was called climate change, now it’s actually called extreme weather because with extreme weather you can’t miss,” the president said.

Environmental watchdog groups now advocate calling the phenomenon “climate catastrophe.”

It seemed to me that Trump is learning from his briefings with William Happer, and is finding the weak spots in the alarmist house of cards.  It also reminded me of a previous post describing the complexity of tracking climate change.  That essay is reprinted below because it reminds us that not only does climate change both ways, but also the warming and cooling can happen concurrently in some times and places.

Concurrent Climate Warming and Cooling

This post highlights recent interesting findings regarding past climate change in NH, Scotland in particular. The purpose of the research was to better understand how glaciers could be retreating during the Younger Dryas Stadia (YDS), one of the coldest periods in our Holocene epoch.

The lead researcher is Gordon Bromley, and the field work was done on site of the last ice fields on the highlands of Scotland. 14C dating was used to estimate time of glacial events such as vegetation colonizing these places. Bromely explains in article Shells found in Scotland rewrite our understanding of climate change at siliconrepublic. Excerpts in italics with my bolds.

By analysing ancient shells found in Scotland, the team’s data challenges the idea that the period was an abrupt return to an ice age climate in the North Atlantic, by showing that the last glaciers there were actually decaying rapidly during that period.

The shells were found in glacial deposits, and one in particular was dated as being the first organic matter to colonise the newly ice-free landscape, helping to provide a minimum age for the glacial advance. While all of these shell species are still in existence in the North Atlantic, many are extinct in Scotland, where ocean temperatures are too warm.

This means that although winters in Britain and Ireland were extremely cold, summers were a lot warmer than previously thought, more in line with the seasonal climates of central Europe.

“There’s a lot of geologic evidence of these former glaciers, including deposits of rubble bulldozed up by the ice, but their age has not been well established,” said Dr Gordon Bromley, lead author of the study, from NUI Galway’s School of Geography and Archaeology.

“It has largely been assumed that these glaciers existed during the cold Younger Dryas period, since other climate records give the impression that it was a cold time.”

He continued: “This finding is controversial and, if we are correct, it helps rewrite our understanding of how abrupt climate change impacts our maritime region, both in the past and potentially into the future.”

The recent report is Interstadial Rise and Younger Dryas Demise of Scotland’s Last Ice Fields G. Bromley A. Putnam H. Borns Jr T. Lowell T. Sandford D. Barrell  First published: 26 April 2018.(my bolds)

Abstract

Establishing the atmospheric expression of abrupt climate change during the last glacial termination is key to understanding driving mechanisms. In this paper, we present a new 14C chronology of glacier behavior during late‐glacial time from the Scottish Highlands, located close to the overturning region of the North Atlantic Ocean. Our results indicate that the last pulse of glaciation culminated between ~12.8 and ~12.6 ka, during the earliest part of the Younger Dryas stadial and as much as a millennium earlier than several recent estimates. Comparison of our results with existing minimum‐limiting 14C data also suggests that the subsequent deglaciation of Scotland was rapid and occurred during full stadial conditions in the North Atlantic. We attribute this pattern of ice recession to enhanced summertime melting, despite severely cool winters, and propose that relatively warm summers are a fundamental characteristic of North Atlantic stadials.

Plain Language Summary

Geologic data reveal that Earth is capable of abrupt, high‐magnitude changes in both temperature and precipitation that can occur well within a human lifespan. Exactly what causes these potentially catastrophic climate‐change events, however, and their likelihood in the near future, remains frustratingly unclear due to uncertainty about how they are manifested on land and in the oceans. Our study sheds new light on the terrestrial impact of so‐called “stadial” events in the North Atlantic region, a key area in abrupt climate change. We reconstructed the behavior of Scotland’s last glaciers, which served as natural thermometers, to explore past changes in summertime temperature. Stadials have long been associated with extreme cooling of the North Atlantic and adjacent Europe and the most recent, the Younger Dryas stadial, is commonly invoked as an example of what might happen due to anthropogenic global warming. In contrast, our new glacial chronology suggests that the Younger Dryas was instead characterized by glacier retreat, which is indicative of climate warming. This finding is important because, rather than being defined by severe year‐round cooling, it indicates that abrupt climate change is instead characterized by extreme seasonality in the North Atlantic region, with cold winters yet anomalously warm summers.

The complete report is behind a paywall, but a 2014 paper by Bromley discusses the evidence and analysis in reaching these conclusions. Younger Dryas deglaciation of Scotland driven by warming summers  Excerpts with my bolds.

Significance: As a principal component of global heat transport, the North Atlantic Ocean also is susceptible to rapid disruptions of meridional overturning circulation and thus widely invoked as a cause of abrupt climate variability in the Northern Hemisphere. We assess the impact of one such North Atlantic cold event—the Younger Dryas Stadial—on an adjacent ice mass and show that, rather than instigating a return to glacial conditions, this abrupt climate event was characterized by deglaciation. We suggest this pattern indicates summertime warming during the Younger Dryas, potentially as a function of enhanced seasonality in the North Atlantic.

Surface temperatures range from -30C to +30C

Fig. 1. Surface temperature and heat transport in the North Atlantic Ocean.  The relatively mild European climate is sustained by warm sea-surface temperatures and prevailing southwesterly airflow in the North Atlantic Ocean (NAO), with this ameliorating effect being strongest in maritime regions such as Scotland. Mean annual temperature (1979 to present) at 2 m above surface (image obtained using University of Maine Climate Reanalyzer, http://www.cci-reanalyzer.org). Locations of Rannoch Moor and the GISP2 ice core are indicated (yellow and red dots).

Thus the Scottish glacial record is ideal for reconstructing late glacial variability in North Atlantic temperature (Fig. 1). The last glacier resurgence in Scotland—the “Loch Lomond Advance” (LLA)—culminated in a ∼9,500-km2 ice cap centered over Rannoch Moor (Fig. 2A) and surrounded by smaller ice fields and cirque glaciers.

Fig. 2. Extent of the LLA ice cap in Scotland and glacial geomorphology of western Rannoch Moor. (A) Maximum extent of the ∼9,500 km2 LLA ice cap and larger satellite ice masses, indicating the central location of Rannoch Moor. Nunataks are not shown. (B) Glacial-geomorphic map of western Rannoch Moor. Distinct moraine ridges mark the northward active retreat of the glacier margin (indicated by arrow) across this sector of the moor, whereas chaotic moraines near Lochan Meall a’ Phuill (LMP) mark final stagnation of ice. Core sites are shown, including those (K1–K3) of previous investigations (14, 15).

When did the LLA itself occur? We consider two possible resolutions to the paradox of deglaciation during the YDS. First, declining precipitation over Scotland due to gradually increasing North Atlantic sea-ice extent has been invoked to explain the reported shrinkage of glaciers in the latter half of the YDS (18). However, this course of events conflicts with recent data depicting rapid, widespread imposition of winter sea-ice cover at the onset of the YDS (9), rather than progressive expansion throughout the stadial.

Loch Lomond

Furthermore, considering the gradual active retreat of LLA glaciers indicated by the geomorphic record, our chronology suggests that deglaciation began considerably earlier than the mid-YDS, when precipitation reportedly began to decline (18). Finally, our cores contain lacustrine sediments deposited throughout the latter part of the YDS, indicating that the water table was not substantially different from that of today. Indeed, some reconstructions suggest enhanced YDS precipitation in Scotland (24, 25), which is inconsistent with the explanation that precipitation starvation drove deglaciation (26).

We prefer an alternative scenario in which glacier recession was driven by summertime warming and snowline rise. We suggest that amplified seasonality, driven by greatly expanded winter sea ice, resulted in a relatively continental YDS climate for western Europe, both in winter and in summer. Although sea-ice formation prevented ocean–atmosphere heat transfer during the winter months (10), summertime melting of sea ice would have imposed an extensive freshwater cap on the ocean surface (27), resulting in a buoyancy-stratified North Atlantic. In the absence of deep vertical mixing, summertime heating would be concentrated at the ocean surface, thereby increasing both North Atlantic summer sea-surface temperatures (SSTs) and downwind air temperatures. Such a scenario is analogous to modern conditions in the Sea of Okhotsk (28) and the North Pacific Ocean (29), where buoyancy stratification maintains considerable seasonal contrasts in SSTs. Indeed, Haug et al. (30) reported higher summer SSTs in the North Pacific following the onset of stratification than previously under destratified conditions, despite the growing presence of northern ice sheets and an overall reduction in annual SST. A similar pattern is evident in a new SST record from the northeastern North Atlantic, which shows higher summer temperatures during stadial periods (e.g., Heinrich stadials 1 and 2) than during interstadials on account of amplified seasonality (30).

Our interpretation of the Rannoch Moor data, involving the summer (winter) heating (cooling) effects of a shallow North Atlantic mixed layer, reconciles full stadial conditions in the North Atlantic with YDS deglaciation in Scotland. This scenario might also account for the absence of YDS-age moraines at several higher-latitude locations (12, 36–38) and for evidence of mild summer temperatures in southern Greenland (11). Crucially, our chronology challenges the traditional view of renewed glaciation in the Northern Hemisphere during the YDS, particularly in the circum-North Atlantic, and highlights our as yet incomplete understanding of abrupt climate change.

Summary

Several things are illuminated by this study. For one thing, glaciers grow or recede because of multiple factors, not just air temperature. The study noted that glaciers require precipitation (snow) in order to grow, but also melt under warmer conditions. For background on the complexities of glacier dynamics see Glaciermania

Also, paleoclimatology relies on temperature proxies who respond to changes over multicentennial scales at best. C14 brings higher resolution to the table.

Finally, it is interesting to consider climate changing with respect to seasonality.  Bromley et al. observe that during Younger Dryas, Scotland shifted from a moderate maritime climate to one with more seasonal extremes like that of inland continental regions. In that light, what should we expect from cooler SSTs in the North Atlantic?

Note also that our modern warming period has been marked by the opposite pattern. Many NH temperature records show slight summer cooling along with somewhat stronger warming in winter, the net being the modest (fearful?) warming in estimates of global annual temperatures.

I’m with Trump on this one:  Climate shifts are not a matter of one-way warming, as we have been told.

 

Stop Fake Science. Approve the PCCS!

John Droz makes some good points writing at Town Hall.Stop Fake Science. Approve the PCCS! Excerpts in italics with my bolds, images and header questions.

Shouldn’t We Get Independent Advice Before We Spend Trillions of Dollars?

Not to date myself, but in my day the “$64,000 Question” represented a lot of money!

Today I’m proposing to you a $64 Trillion question: “Should the United States conduct a full, independent expert scientific investigation into the models and studies that say we face a serious risk of manmade global warming, climate change and extreme weather disasters?”

That independent expert investigation is what’s being proposed by Dr. Will Happer, President Trump’s Senior Director for Emerging Technologies, in the National Security Council. Specifically, a brand new Presidential Committee on Climate Science (PCCS) will do this analysis. The decision about launching the PCCS will be made in the next few days. America’s support for President Trump is urgently needed.

(For the sake of brevity – and to use the most commonly employed term – when I say “global warming,” I mean all the climate changes that are supposedly caused by fossil fuel use and other human activities.)

$64 Trillion is actually at the lower end of estimates of what it will cost the USA over the next decade to replace all our fossil fuel use with (supposedly) green, renewable, sustainable wind, solar and biofuel energy – in order to (supposedly) stabilize Earth’s climate (which has never been stable).

Many say the obvious answer to this $64 Trillion question is YES, of course. However, many other parties are saying NO. What are the arguments against the PCCS, and do they hold water?

If the case for alarm is so convincing, what’s the problem?

1) It’s a waste of money to have this PCCS investigation. If the US was about to spend an enormous amount of money – such as $64 trillion or more – would you say an investigation costing one-billionth(!) of that monumental expenditure would be a waste of money? That’s what we are talking about here.

2) It’s a waste of time. President Trump has already stated that (without new facts confirming that we actually face imminent manmade climate chaos) he’s not going to do anything consequential about global warming. So since the USA is in a holding period on this issue, how is any time being wasted?

In fact, since the President is asking for an independent investigation, the end result could be that the PCCS would recommend that Mr. Trump take a different global warming policy position, and actually support action against fossil fuels. One would think those clamoring for exactly that would be ecstatic!

3) Human responsibility for climate change and extreme weather has already been scientifically resolved. That is simply not so. A genuine scientific assessment has four necessary components. It must be: a) comprehensive, b) objective, c) transparent, and d) empirical. There has never been a true scientific assessment of global warming claims, anywhere on the planet.


How about the many scientists who have valid questions about the evidence?

What about the position of 97% of the world’s scientists? That’s a good question, because we constantly hear that virtually the entire scientific community agrees that humans are causing climate catastrophes.

Fact one: there never has been a survey of the world’s 2+ million scientists on anything – certainly not on this vital issue, which is being used to demand the immediate end to all use of fossil fuels that today provide over 80% of all the energy the United States and entire world use.

Fact two: There may indeed be a majority of certain subsets of scientists who hold an opinion about global warming. However, many who support climate cataclysm claims receive government or other grants that would be terminated if they began to “question the science of global warming.” And not one of them has ever conducted a genuine, evidence-based scientific analysis of the global warming matter.

Fact three: Science is never determined by a vote. Do you think that Einstein’s Theory of Relativity was accepted due to a poll? Or was it because his theory survived extensive scientific scrutiny?

What about the UN Intergovernmental Panel on Climate Change’s voluminous Assessment Reports?

Another good question. However, if we compare the reports to the four necessary requirements for Real Science, as practiced for centuries, they actually fail on at least three of the four criteria that I just presented a few paragraphs ago!

If the global warming cataclysm proponents’ scientific arguments were as unassailable as they say they are, then those scientists should relish this high-profile opportunity to publicly upstage the skeptics and prove to the world that “dangerous manmade climate change” is real.

On the other hand, those alarmist scientists might fail spectacularly. They might be shown to have no real-world evidence to back up their computer models and assertions. I submit that they are scared to death this would happen. That is why they oppose the PCCS so stridently.

How about our long history of coping with changes in climate and weather extremes?

4) Global Warming is a national security threat. This is another three-card-Monte trick being played on the technically-challenged public. Multiple studies have shown there is little correlation between extreme weather events (e.g. hurricanes, tornadoes, floods) and global warming. Moreover, our military – indeed our entire country and civilization – have been dealing with these problems for centuries, and today we have far better technologies to do so than ever before.

On the other hand, one of the key “solutions” to Global Warming (industrial wind energy), has a well-documented history of interfering with the missions and operational readiness of our military. Where is the outcry against that?

What’s wrong with asking questions about actions being promoted?

5) President Trump is acting irrationally regarding global warming. Surprisingly, President Trump, as a skeptic, is actually taking a more scientific position than many scientists who hold PhDs. Skepticism is the primary pillar of Real Science. So being labeled a “skeptic” is high praise to real scientists.

Unless we pay close attention, it may not be apparent that America’s Left is frequently in favor of exactly the opposite of what they are now saying. For example:

* The people who say they want more unity – are actually instigating divisiveness.

* The people who say they are protectors of the environment – are actually doing the most to ravage the environment, by demanding energy systems that require far more land, far more raw materials, and far more environmental damage than fossil fuels have ever caused.

* The people who say immediate, extraordinary, highly disruptive changes are needed to prevent global warming catastrophe – are promoting feeble, inadequate solutions: like wind and solar energy.

So when these same people clamor that they want President Trump to reverse his position on global warming (and the Paris Climate Accord – in reality they actually want President Trump to continue with his present climate policies and skepticism. Why is that?

Because they think that will give them political ammunition to use against him in the 2020 election.

 Shouldn’t we try to separate private interests from the public good?

The bottom line is very simple. President Trump should be applauded for proposing the PCCS, and for being open-minded enough to reconsider global warming claims – before our nation accepts them as gospel … and rushes headlong into disrupting our energy, economy, living standards and lives … probably for no climate benefit whatsoever.

We citizens need to support him against the very vocal (and often very self-interested) people and organizations that strongly oppose the Presidential Committee on Climate Science. We need to take immediate action to support President Trump on this vitally important initiative.

Send him a quick note. Real, evidence-based climate science demands that we have this PCCS review. So does the future of our country and our children.

A Critical Framework For Climate Change

This dialogue framework was proposed for a debate between William Happer and David Karoly sponsored by The Best Schools.  As you can see it reads like an high hurdle course for alarmists/activists.  There are significant objections at every leap in connecting the beliefs.

Happer’s Statement: CO₂ will be a major benefit to the Earth

Earth does better with more CO2.  CO2 levels are increasing

Atmospheric transmission of radiation: Tyndall correctly recognized in 1861 that the most important greenhouse gas of the Earth’s atmosphere is water vapor. CO2 was a modest supporting actor, then as now.

Radiative cooling of the Earth: Clouds are one of the most potent factors controlling Earth’ s surface temperature.

The Schwarzschild equation:  The observed intensity I of upwelling radiation comes from the radiation emitted by the surface and by greenhouse gases in the atmosphere above the surface. The rate of change of the intensity with altitude is given by the Schwarzschild equation.

Logarithmic forcing by CO2:  The intensity for a doubling of CO2 concentrations from the present value of 400 ppm to 800 ppm makes little difference, and simply leads to a slight broadening of the width of the band.

Convection:  Radiation, which we have discussed above, is an important part of the energy transfer budget of the earth, but not the only part.

Numerical Modeling:  Predictions about what more CO2 will do to the Earth’s climate are based on numerical modeling of the fluid flows in the atmosphere and oceans.  Including water vapor, clouds, and precipitation further complicates the modeling considerations outlined above. Climate model builders have a hard job.

Equilibrium Climate Sensitivity: If increasing CO2 causes very large warming, harm can indeed be done. But most studies suggest that warmings of up to 2 K will be good for the planet.  More than a century after Arrhenius, and after the expenditure of many tens of billions of dollars on climate science, the official value of S still differs little from the guess that Arrhenius made in 1912: S = 4 K. Could it be that the climate establishment does not want to work itself out of a job?

Overestimate of S:  Contrary to the predictions of most climate models, there has been very little warming of the Earth’s surface over the last two decades.  If one assumes negligible feedback, where other properties of the atmosphere change little in response to additions of CO2, the doubling efficiency can be estimated to be about S = 1 K. The much larger doubling sensitivities claimed by the IPCC, which look increasingly dubious with each passing year, are due to “positive feedbacks.”

Benefits of CO2:  More CO2 in the atmosphere will be good for life on planet earth. Few realize that the world has been in a CO2 famine for millions of years — a long time for us, but a passing moment in geological history.

More bogeymen: The earth has stubbornly refused to warm nearly as much as demanded by computer models. To cope with this threat to full employment, the climate establishment has invented a host of bogeymen, other supposed threats from more CO2.  One of the bogeymen is that more CO2 will lead to, and already has led to, more extreme weather, But extreme weather is not increasing.  We also hear that more CO2 will cause rising sea levels to flood coastal cities, large parts of Florida, tropical island paradises, etc.

Climate Science:  Too much “climate research” money is pouring into very questionable efforts, like mitigation of the made-up horrors mentioned above. It reminds me of Gresham’s Law: “Bad money drives out good.”

Summary

The Earth is in no danger from increasing levels of CO2. More CO2 will be a major benefit to the biosphere and to humanity.

Karoly’s Statement: Climate change is harming nature and humanity

1. Observed global warming is beyond reasonable doubt

2. Increases in greenhouse gases are due to human activity

3. Most of the observed global warming since the mid-twentieth century is due to human activity

4. Global warming will continue over the twenty-first century

5. Many adverse impacts result from global warming

6. Substantial reductions in greenhouse gas emissions are needed to minimize dangerous global warming

Summary

The key points presented above are just a small fraction of the vast body of evidence that support the scientific conclusions on global warming accepted by all the scientific Academies and by all the governments around the world.

Science has established that it is virtually certain that increases of atmospheric CO2 due to burning of fossil fuels will cause climate change that will have substantial adverse impacts on humanity and on natural systems. Therefore, immediate stringent measures to suppress the burning of fossil fuels are both justified and necessary.

Happer’s detailed response to Karoly on climate change

Dr. Karoly begins his Statement, not with evidence to support the title, “Climate change is harming nature and humanity,” but with a summary of what happened in the “21st Conference of Parties to the United Nations Framework Convention on Climate Change in December of 2015.” What a mouthful!

As I pointed out in my Interview and Statement, there is no scientific evidence that global greenhouse gas emissions will have a harmful effect on climate. Quite the contrary, there is very good evidence that the modest increase in atmospheric CO2 since the start of the Industrial Age has already been good for the Earth and that more will be better.

Some climate scientists, including Dr. Karoly, are doing praiseworthy work. I especially admire high-quality, year-by-year measurements of properties of the atmosphere and oceans. But if they have doubts about climate hysteria, most practicing climate scientists keep these to themselves because of the ferocity of the attacks they know will come to those who question the party line.

In my Interview, I mentioned the attacks on me by Greenpeace. No wonder there is a consensus of climate scientists, or that few scientists from other fields are willing to question the established dogma!  Even though creative scientists are not greatly impressed by them, claims of consensus work wonders with educated elites.

A brief discussion of those key points of Dr. Karoly’s Statement with which I disagree:

3. “The observed large-scale increase in surface temperature across the globe since the mid-twentieth century is primarily due to human activity, the increase of greenhouse gases in the atmosphere, and other impacts on the human climate system.”  This statement is based on excessive faith in computer models.

Trends in global mean surface temperature. a. 1993-2012. b. 1998-2012. Histograms of observed trends (red hatching) are from 100 reconstructions of the HadCRUT4 dataset. Histograms of model trends (grey bars) are based on 117 simulations of the models, and black curves are smoothed versions of the model trends. The ranges of observed trends reflect observational uncertainty, whereas the ranges of model trends reflect forcing uncertainty, as well as differences in individuals model responses to external forcings and uncertainty arising from internal climate variability.

4. “There will continue to be significant global warming over the 21st century with its magnitude depending on the emissions of greenhouse gases from human activities.”  Again, this is a statement based on computer models. No one knows how the temperature of the Earth will change over the twenty-first century. It is just as likely that the Earth will cool, since whatever mechanism caused the Little Ice Age could act again and could overwhelm the small warming expected from increased CO2. In both my Statement and my Interview, I pointed out how much most models overestimated the warming of the Earth since the year 2000, when there was a hiatus or pause in warming, which may not be over yet.

5. “There are substantial adverse impacts on human and natural systems from global warming.” I disagree. I don’t know of a single adverse impact that can be confidently ascribed to more CO2. There are plenty of phony claims of damage, which quickly fall apart when scrutinized.

6. “Rapid, substantial, and sustained reductions in greenhouse gas emissions from human activities are needed to slow global warming and stabilize global temperature at a level that would minimize dangerous human influence on the climate system.”  I disagree. We are being exhorted to “reduce our carbon footprint,” although to Dr. Karoly’s credit, he does not use this silly slogan. To the extent that “carbon footprint” includes soot (small particles of elemental carbon), and CO, carbon monoxide molecules, I would be glad to be part of the crusade.

General Comments

My Statement had 64 citations. I, too, cited many government reports, including those of the IPCC, but I also cited at least 16 peer-reviewed papers by independent scientific researchers. Dr. Karoly’s overwhelming focus on government reports looks like fully developed groupthink. Or maybe it is better described by the old Russian proverb:

Сила есть, ума не надо.

We have power, no need for intelligence.

Trotsky refers to the old principle which St. Paul states in 2 Thessalonians chapter 3:10 “We gave you this rule: if a man will not work, he shall not eat.” And before that Deuteronomy 25:4: “Do not muzzle an ox while it is treading out the grain.”

Enormous imagination has gone into showing that increasing concentrations of CO2 will be catastrophic. Cities will be flooded by sea-level rises that are 10 or more times bigger than even the IPCC predicts. There will be mass extinctions of species; billions of people will die; “tipping points” will render the planet a desert.

If you wrote down all the ills attributed to global warming, you would fill up a very thick book. And all of this despite the fact that in the history of higher life forms on Earth (the Phanerozoic), CO2 levels were four or more times higher than today, but life nevertheless flourished at least as abundantly on land and in the sea as it does today. It’s an ill wind, indeed, that blows no good.

In summary, Dr. Karoly is a good scientist who means well. But he lives in an echo chamber of like-minded people who are convinced that they are saving the world.

The scholars of the floating island of Laputa had much in common with many promoters of global-­warming alarmism