Guest posts by Willis Eschenbach
This is an extension of my previous post titled “February fantasy vs reality“. Please read it to get the basic idea. In short, one study in the journal Science said
Despite the rapid warming that is a key sign of global climate change, especially in the Arctic, where temperatures are rising much higher than elsewhere in the world, the United States and other regions Other Northern Hemispheres have experienced a significant and increasingly frequent amount of extremely cold winter weather over the past four decades.
…
The Arctic is warming at twice the global average rate, and severe winter weather is reported to be increasing in many densely populated mid-latitude areas, but there is no agreement on it. whether there is a physical connection between the two phenomena.
To test the boost statement “severe winter weather”, in my previous post, I looked at the average February temperature for the continental US to see if it was cool. It is not cooled.
However, some commenters have correctly pointed out that the issue discussed in the study is not the average temperature. Instead, the authors talked about “extremely cold winter weather episodes” such as what Texas experienced in February 2011 and 2021.
Looking for a more accurate measurement of extremely cold winter weather, I received daily temperature data for the Southern Great Plains from DO NOT HAVE. Here is a map of the area in question.
Figure 1. Map of the National Climate Assessment regions.
Then I calculate the standard deviation (a measure of how wide a temperature spreads) of the February temperatures. I reasoned that if there were strong, short cold spells, the standard deviation would be larger.
Figure 2. Standard deviation of February daily minimum temperature for the Southern Great Plains. Cold spells are represented by an increase in standard deviation.
In Figure 2, we can clearly see the Texas cold spells in 2011 and 2021. But is there “The number of episodes of extremely cold winter weather has become increasingly frequent and conspicuous over the past four decades”?
Well… in a word, are not. Figure 2 shows a severe cold in 1951. And Texas State Climatologist agree, say:
January–February. 1951: Freeze. On January 31 – February. On February 3 and again on February 13–17, cold waves swept across the entire state, bringing snow and hail. Severe damage has occurred in the Lower Rio Grande Valley to truckload and citrus crops, notably in earlier northern regions. During the northern part of January 31 to February. On October 3, the temperature reached -19°F in Dalhart.
However, in the thirty years after 1951, there were few obstacles.”extremely cold winters” until the decade and a half from 1981 to 1996. During that time there were some cold spells, though not as intense as February 1951. The coldest was in February 1985, San Antonio rarely snowed, and they witnessed the coldest day ever recorded in Midland, Texas.
However, in the quarter of a century since 1996, there have been only two extreme cold spells mentioned above, in 2011 and 2021.
If we divide the 72 years of the record into three 24-year periods, we only have one “period of extremely cold winter weather” in the first period; six sections warmer in the second period; and only two episodes in the last 24 years.
So no, in the Southern Great Plains, yes Not one “The number of extremely cold winter weather events is increasing. It’s not “severe winter weather…increasingly” as they stated. Both of those statements are not true.
Then I thought, “Well, maybe I’m looking too far south. It is possible that the effect is claimed to be visible in the Northern Great Plains”. So it went back to the drawing board, and this is what I found.
Figure 3. Standard deviation of daily minimum temperature in February for Northern Great Plains. Cold spells are represented by an increase in standard deviation
Although there is a larger difference in February minimum temperatures in the North Great Plains NCA, the same situation is common as in the Southern Great Plains—a February.”period of extremely cold winter weather” for the first 24 years, about half a dozen in the middle 24 years, and two cold Februarys in 2011 and 2021 for the last 24 years. And there are no trends in the data.
Another beautiful theory runs aground on a string of ugly truths.
Best for all,
w.
Data access—I have put daily temperatures in the Southern Great Plains for 72 years (1951-2022), both maximum and minimum temperatures, into my Dropbox for download. It’s a pretty small file named Great Plains South nClimDiv.csv588 KB, in CSV format so that it can be opened with Excel or other programs.
My usual—I can defend my word. I choose them very carefully. I cannot defend your misunderstanding (wrong) of my words. So please, when you comment, quote exactly the words you are discussing.
Related
