Again this week I got an email from a friend linking to an alarmist website claiming (among other things) 2015 the Hottest Year Ever, August 2016 the Hottest Month Ever, 16 Hottest Months in a row, The Earth is Burning!
My reply:
Calm down and breathe through your nose. Be not afraid.
You have been misinformed, and I will tell you how and why.
1. “Hotter” does not describe a long period when daily highs are falling, not rising. That’s right, generally the temperature records are showing a decline over time in the maximums recorded at the weather stations.
For example look at results from USHCN (US Historical Climate Network) for the trend of daily maximums since 1930.
Source: Tony Heller, Real Climate Science
It is clear that measurements of actual afternoon highs are trending down in most places, and lower much more strongly than the few increases. Below the same results displayed geographically.
2. Temperature averages over decades show great climate stability, not change. The calculated trends are in fractions of a degree Celsius, well within the error range of the instruments.
Alarmists favor the dataset from GISS, a part of NASA. They fabricate estimates of an hypothetical Global Mean Temperature not from satellites, but by taking weather station records and performing various statistical manipulations, including adjusting, deleting, infilling, gridding, weighting, homogenizing, and averaging.
Out of all that processing they produce estimates of annual GMTs, which can not be attributed to any actual observation. More importantly, the dataset is unstable–past history, for example the 1930s, appears in GISS graphs with different values this year than last, and different again from 5 and 10 years ago. As Dr. Ole Humlum commented: A temperature record which keeps on changing the past hardly can qualify as being correct.
Below is shown GISS estimates in the context of human experience of daily and seasonal temperature variability.
3. The planet has a vast array of climates, each of which has it’s own experience of changing weather and longer term patterns. That is evident in the first chart above. It is also the case that generally as daily highs have been falling, daily lows (minimums) have been rising more strongly, resulting in slightly increasing daily averages. That is the basis for claiming hottest years and months.
This phenomenon is widespread around the world, as demonstrated by studies reported here at this blog under the category Temperature Trend Analysis. For example, Analyzing Temperature Change using World Class Stations.
In addition, 70% of the GISS surface temperatures are from SSTs (sea surface temperatures), meaning that ocean cycles like El Nino dominate the results. Short-term variations recently derive from changes in the Pacific basin, the largest of the world’s oceans.
Because climates are local and plural, any general statement about warming or cooling does not necessarily apply to the place where you live.
Summary
The next time you read or are told the world is getting hotter, you should respond along these lines.
“You have been misinformed. It is not getting hotter, it has become milder. The temperature records show fewer extremes of highs and lows, milder Winters, earlier Springs and later Autumns. The longer growing seasons are producing bumper crops almost every year.
Instead of complaining about hotter weather, we should enjoy the bounty of harvests Nature is providing to us.”
The 2016 harvest is shaping up to be a whopper, according to Western Canada’s largest elevator companies.
Footnote:
Another post Arctic Warming Unalarming reports on in depth analysis of 118 weather stations around the Arctic Circle, where so-called “Arctic amplification” should be evident. The conclusions:
The Arctic has warmed at the same rate as Europe over the past two centuries. . . The warming has not occurred at a steady rate. . .During the 1900s, all four (Arctic) regions experienced increasing temperatures until about 1940. Temperatures then decreased by about 1 °C over the next 50 years until rising in the 1990s.
For the period 1820–2014, the trends for the January, July and annual temperatures are 1.0, 0.0 and 0.7 °C per century, respectively. . . Much of the warming trends found during 1820 to 2014 occurred in the late 1990s, and the data show temperatures leveled off after 2000. (my bold).
So, consistent with statements above: No increase in July temperatures, some warming overall due mostly to January.
Science Matters 
Ron,
Whilst the evidence shows that global average temperatures are now slightly higher than in 1910, it is the scale of the warming and the variations across the globe that is interesting. Last year (with a little prompting in the right direction from you in the comments) I looked at the issues of homogenisation adjustments. What I found was that the temperature trends were quite different. This was not just in magnitude (Parts of Northern Siberia have warmed at a rate many times greater than most other areas) but in timing. Some odd places have bucked the trend. In a post Defining “Temperature Homogenisation” I tried to understand the difference between the definition and what was actually achieved. Two quotes illustrate the problem.
Venema et al 2012 stated
But examination of the data shows that the assumption of consistency breaks down. A well-known blogger fairly accurately describing real-world homogenisation processes said
GISS do not just take the data from 1880 to the present day of all the temperature stations and homogenize it to the present day. They add new data and then homogenize the entire data set, most of which has already been reprocessed a number of times before. Each time that happens data that had previous historical data that seemed compatible, is now incompatible. The data homogenisers have to then make subjective decisions. As they usually believe that the world should be warming faster than it is, they will find reasons to accept temperature station data slightly above the surrounding temperature stations, but will not accept reasons to accept temperature station data slightly below.
In the follow up I postulated that the impact of repeated homogenisations by believers in a strong AGW impact could affect the temperature record. That is to continually reduce the early twentieth century warming relative to the late twentieth century. I also suggested ways that this could be tested.
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manic, thanks for the links to your interesting analyses. I noticed this is your followup piece:
“Figure 1 shows the NASA Gistemp global anomaly in black along with a split be eight bands of latitude. Of note are the polar extremes, each covering 5% of the surface area.”
You alluded to the thinning out of weather stations reports, especially in the North, and issue I addressed in this post: https://rclutz.wordpress.com/2016/08/09/nunavut-is-melting-or-not/. Included there is mention of Eureka Canada, “the last station above latitude 65N.” Also, there is a link to that depth analysis of 118 Arctic Circle station records, which show unalarming warming, and mostly in January.
I appreciate your efforts to get at the mechanisms by which temperature reconstruction products like GISTEMP manage to make global estimates so out of tune with local measurements. I suspect that we may not get to the bottom of it, since they are so resistant to information requests from the US House Space and Technology committee.
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Reblogged this on Climate Collections.
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