Credit: USDA
WASHINGTON, DC –A new study shows extreme heat events both in the summer and in the winter are increasing across the U.S. and Canada, while extreme cold events in summer and winter are declining.
A new study in the in Journal of Geophysical Research: Atmospheres, a publication of the American Geophysical Union, examined absolute extreme temperatures–high temperatures in summer and low temperatures in winter–but also looked at relative extreme temperature events–unusually cold temperatures and unusually warm temperatures throughout the year.
The new study found both relative and absolute extreme heat events have increased across the US and Canada since 1980. This upward trend is greatest across the southern US, especially in the Ozarks and southern Arizona, as well as northern Quebec. That means there are more extremely hot days during the summer as well as more days that are considered extremely hot for the time of year, like abnormally warm days in the winter.
The new research also found both relative and absolute extreme cold events are decreasing, most notably in Alaska and Northern Canada, along with patches along the US Atlantic coast. In these areas, there are fewer instances of temperatures that are extremely cold either compared to the normal range, like in winter, or for the time of year, like unusually cold days in the summer.
Global mean surface temperature, the most frequently cited indicator of climate change, has been steadily increasing since the 1970s. However, temperature extremes pose a greater ecological risk to many species than average warming, according to the study’s authors.
The new study is one of the first to explore relative extreme temperature events, which are changing more rapidly than absolute temperature extremes, and can have important implications for the environment, agriculture and human health, according to Scott Sheridan, professor in the department of geography at Kent State University and lead author of the new study.
“Typically for this kind of research we look at the highest temperatures in the summer and lowest temperatures in the winter. But we’ve also seen that extreme temperatures that are really anomalous for the time of year can have a high impact–these relative extremes are important and underappreciated,” he said.
Investigating temperature extremes
To investigate how extreme temperature events have been changing over time, Sheridan and his co-author conducted a climatology of cold and heat events, both absolute and relative, for North America, followed by an analysis of how they have changed from 1980-2016.
Relative extreme temperature events are changing faster than absolute extreme events, and often occur outside of seasonal norms, according to the new study. In the eastern half of the US, relative extreme heat events occur as early as mid-winter into early spring. Out-of-season extreme temperatures can cause early thaws in mild winters or catch vulnerable populations unprepared and unacclimated.
Across parts of the Arctic, extreme cold events have become almost entirely nonexistent and increasingly difficult to identify, according to the researchers.
“Relative temperature anomalies can trigger what are called phenological mismatches, where a mismatch in the temperature and the season can cause trees to bloom too early and birds and insects to migrate before there is appropriate food,” Sheridan said.
Most notable is the highly anomalous warm event in March 2012, which included persistent mid-summer warmth in multiple locations. The event produced a ‘false spring’ in which vegetation prematurely left dormancy, so that it was not prepared for subsequent frosts, leading to large agricultural losses in certain areas, according to the researchers.
There is some evidence that early-season heat events are more hazardous to humans than heat events later in the season. When people are not acclimatized to hotter temperatures, they are more vulnerable to negative health impacts, especially the elderly, infants, young children, and people with chronic health problems or disabilities, according to the researchers.
The study clearly underlines the importance of not just looking at high temperatures in the summer but also looking at relative temperatures, said Kristie Ebi, professor of Environmental and Occupational Health Sciences at the University of Washington, who was not involved in the study.
“Using information generated in the study on regional patterns in extreme weather events, particularly relative extremes in temperature, early warnings could be issued that include information on what people can do to protect themselves and to protect crops and ecosystems,” Ebi said.
###
High temperatures have increased during the warm phase of the PDO/AMO.
Who’d a thunk it.
Meanwhile, stocks of wheat, corn and soybeans have increased to the point where we’re running out of places to put the stuff. The climate must be getting friendlier to agriculture.
Oh, pish-tush. Weather isn’t the same thing as climate.
Late, chilly spring means the bugs come out late, the trees don’t break buds by mid-April like they’re supposed to and we get an EARLY winter slush-to-snow and below average temperature blizzard in November, when it would normally come in December through February. Ain’t no heat involved in that stuff, except for what’s on my gas bill.
What’s next? Fire from volcanoes? Already have that one in an ongoing state. Devastating storms? All during this past summer, and another one started Sunday night, knocked out power to 364,000 people in my AO, shut down roads and businesses and whatever court proceedings were going on. We’ll probably get more of the same. I’m stocked up on food and kitchen matches, and yes, I will get out my grandmother’s oil lamps and fill the bowls with lamp oil if I have to.
I now have a sort of crush on the linemen from the power company who worked for 4 hours on a thankless task Monday evening from 4PM to 8PM, just to get the electricity back up and running in my neighborhood. All my neighbors were in their cars, trying to stay warm.
Extreme heat? 92F in July is normal, you know. 14F in November is a little odd, but – well, we survived it and we’re all better now.
Conspiracy theories are the work of idiots. I can come up with better stories in the blink of an eye. You guys better stock up on vinegar. Have you watched your trees to see if crows are rooking up there? If they are, you should make sure that your trash is bagged and in the trash bin where it belongs. Otherwise, they’ll stick around to rummage through it.
Oaks in Poland had an extremely large number of acorns. Russian frost is coming.
Since it is demonstrable from NOAA data that absolute e tremes are NOT increasing, the paper invents relative extremes to finally find something increasing.
I’m going to start worrying when it gets to be -14c in summer and + 30c in winter. Until then it is just weather and more warmest blather. (Unless some major strato-volcano blows somewhere in which case just wait a while.)
“Across parts of the Arctic, extreme cold events have become almost entirely nonexistent and increasingly difficult to identify, according to the researchers.”
Arctic warming is normal during a solar minimum.
“Most notable is the highly anomalous warm event in March 2012, which included persistent mid-summer warmth in multiple locations.”
That would have not existed without short term solar variability, nor would have the very cold March 2013.
I went to the original Texas A & M College just up the road from Navasota during the drought of the 1950s. Much, much, much, much worse. Spring of 1957 flood you could not drive across the Brazos River floodplain.
“ EHE = excess heat event; ECE = excess cold event; REHE = relative excess heat event; RECE = relative excess cold event; ETE = extreme temperature event.” Yep, we lived through it. Freezes of 1947 and 1951, drought from 1947 to 1957, worst part, 1954-57.
At least they got back to 1980. Just drove to Louisiana and back below there near the coast, water, water everywhere. Lush, lush, lush. It’s called Texas.
I should add that I just talked to someone born in Wichita Falls in 1927. He remembers living both through the 30s and 50s. It did get very dry there this decade, but it rained. Texas records go back to the 1880s, before computers. Information available, but it requires homework.
I went into reading this with my hackles up. than I calmed down and said to myself, “Shelly, you have to be open to new information and maybe they know something you don’t.” So I carefully and calmly read the study inbetween deep yoga breaths.
This caught my attention:
We already do this every single day. It’s called the weather channel.
I agree heartily with Zigmaster :
And Samuel was pretty coherent
So why would we expect them to find other wise?
But Richard M allowed me to stop with the deep breahing and go for the deep belly laughs
You know, my dog Moxie helps me predict the weather–or Climate–ah, well global warming. If its warming she runs all over the yard and I have to hollar for her to come back; if its cooling, she pees and runs back inside. If you don’t believe me, Coach Springer, here’s my weather predictor dog, Moxie.
http://www.day-by-day.org/weatherpredictor.jpg
Moxie has a lot more trustworthy face than most sentient beings dealing with … [clear throat] … “forecasting climate”.
Haha! Glad you warned us!
So, I searched for this “new study”, and I found it here (full article, NOT paywalled):
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018JD029150
Sheridan, S. C., & Lee, C. C. (2018). Temporal trends in absolute and relative extreme temperature events across North America. Journal of Geophysical Research: Atmospheres, 123.
The math looks pretty impressive, and the descriptive language is jargonesque to obscure understanding of the calculation for non-tech laypeople such as myself, … BUT this caught my eye:
2.2 Calculation of Extreme Events
The extreme events in this paper are all based on the initial definition of EHF (Nairn & Fawcett, 2014), with the exception that apparent temperature is used instead of temperature.
Now the “with the exception” part of this sentence put me on guard — what’s “apparent temperature” ? They are using NOT “temperature” but “apparent temperature”. Soooooooooo, I had to look up the term to try figuring out what distinction they were making.
As best as I can tell, they are using wind-chill temps and heat-index temps. Well, what if the winds were particularly gusty in some places in certain years?, or what if the humidity was particularly low or high in other places in certain years? And how does this metric using “apparent” temps compare to other studies that might or might not [I don’t know] be talking about the same sorts of highs and lows, calculated the same ways ? And is this really telling us what we need to know at all about temps?, … or is it conflating/contaminating temp data with wind-chill and heat-index data ?
Needless to say, I am suspicious, perhaps ignorantly so, but I’d be curious what math masters here might think.
So, I screwed up my bold face — grrrrrrrrrrrrrr ! — it should have stopped after the word, “temperature” in the calculation sentence.
There’s just something about that “apparent temperature” bugging me. I can’t put my finger on it.
Yeah, they compare like categories of measurement to like categories of measurement over three-day and thirty-day periods, which would seem to be using a consistently defined set of values, but, within each of those values, there seems to be something that is not consistent from value to value.
Is a humidity-value-with-a-temp value comparable to another humidity-value-with-another-temp value? I just get the feeling that the comparison of like measurement to like measurement somehow breaks down.
If heat extremes are more common across the U.S., and they show a field of soybeans in cracked clay-rich dirt as the example, the implication is that these heat extremes are reducing our soybean production?
So I looked up a few years of soybean product – it is trending upwards (amount grown per acre) not downwards. Sooo? What exactly is the problem? We will be growing too much food or something if the trend continues?
They can’t even cherry-pick very well.
The graphs of all agricultural products are trending up with no sign of slowing.
We grow more food now than ever, by any metric one can think of: Yield per hectare, total amount of harvest, acres in production, food per person alive in the world…
And the increases are everywhere in the world, such that the sorts of famines that used to be regular events, requiring massive and immediate food aid, are now virtually unheard of.
Oh hey…forgot this:
Soybeans for five countries back to 1965, and world production of the 3 major grains:
http://www.earth-policy.org/images/uploads/graphs_tables/highlights43_prod_soy.PNG
http://www.earth-policy.org/images/uploads/graphs_tables/indicator3_2012_CornWheatRice.PNG
After 60’s with chemical inputs technology + high yielding seeds + irrigation = increasing trend in yields — I presented these in graph form in my book in 2007 [data in 2000 book]. With rainfed crops it is slow raise with high yielding seed.
Dr. S. Jeevananda Reddy
These “scientists” can’t tell the difference between heat and water. Just because it is hot doesn’t mean it can’t rain. Look at Florida and the South-East. Just because it rains doesn’t mean it is cold…
Another nonsense “study” based on statistical voodoo and cherry-picked data. It means exactly bupkis.
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018JD029150
THIS STUDY IS COMPLETELY FRAUDULENT.
“Three‐hourly values of 2‐m temperature, 2‐m dew point, and 10‐m wind speed (from u‐ and v‐wind components) were obtained from the North American Regional Reanalysis (Mesinger et al., 2006) for all available land points over North America between 23°–84°N and 178°–46°W for the period 1979–2016.
For each 3‐hourly period, an apparent temperature was then calculated based on the Steadman (1984) formula for outdoor shade conditions, where AT = −2.7 + 1.04 T + 2.0P − 0.65u, where T and AT are in degrees Celsius, P is vapor pressure in kilopascals (calculated from dew point), and u is wind speed in meters per second. The Steadman AT was chosen over other apparent temperature metrics as it has typically been used in year‐round analyses such as this study, where a standard single metric is needed across multiple seasons. Daily mean apparent temperature (AT) was then calculated based on the average of the eight 3‐hourly values.”
Nothing was measured. This is all made up nonsense.
How do you spell FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFRAUD?
Like others who have commented, I stopped reading when I got to the part where they cherry-pick the cut off dat for the “study”.
Longer terms trends for extreme weather show exactly the opposite trend.
We see the same disingenuous shenanigans in studies of forest fires, and all sorts of other crap.
And if the data does not show what they want it to, they just change it by any of the several means they have devised to do so.
These jackasses should really be ashamed of themselves for stooping this low to try to prove a lie.
A random choice of a Midwest weather station with a long record and little UHI:
COLUMBUS 3 NE, Nebraska
Period of record: 1893-07-02 to 2018-11-27
Maximum number of consecutive days MAX temperature exceeded 100°F:
1936 – 11
1936 – 10
1940 – 8
1935 – 8
1988 – 7
1936 – 7
1939 – 6
1937 – 6
1930 – 6
1901 – 6
In 2002 and 2012 there were 3 consecutive days >=100, tied for 36th in the entire record.
Maximum number of consecutive days MAX temperature remained below freezing:
1936 – 31
1978 – 28
1979 – 24
1929 – 23
2010 – 22
1983 – 22
1979 – 22
1930 – 22
1895 – 22
1966 – 21
Maximum 7-Day Mean Min Temperature °F,
December 1 to March 1:
2000 – 37.6
1913 – 37.5
2000 – 37.4
2000 – 36.7
1930 – 36.7
1930 – 35.9
2000 – 35.6
1930 – 35.1
1930 – 35.0
2000 – 34.6
1981 – 34.6
1931 – 34.6
Not much of trend there.
The record MAX temperature of 115°F occurred in 1936.
MAX temperature this century was 103 in 2012.
A record low summertime MAX of 94 was set in 2014.
The record MIN temperature of -29°F was last reached in 1912. Last winter it was a balmy -17.
According to the USDA August forecast, Nebraska’s 2018 corn, soybean, sorghum, and winter wheat production will all reach record highs this year.
Oh, woe are we to live in such a frightening political climate!
Correction: first listing should be number of days consecutive days MAX temperature exceeded 99°F
Extreme temperatures have been declining in the United States since the 1930’s. I don’t know how these guys can find just the opposite. It just goes to show how statistics can be used to manipulate the truth.
Here’s a graph from Roy Spencer that is pertinent, “Number of days daily Maximum temperature above 100 F and 105 F (US)”. As you can see, extreme heat has been declining since the 1930’s:
http://www.drroyspencer.com/wp-content/uploads/US-extreme-high-temperatures-1895-2017.jpg
When the data series follow a cyclic variation, analysis of truncated data part of the cycle lead to misleading conclusions. Scientists from IITM sent a note to the minister on Indian southwest monsoon rainfall saying that the rainfall is decreasing. The same, minister informed to the parliament with reference to question. IITM brought out a data series [monthly, seasonal] at met sub-division level for the period 1871 to 1994. I simply calculated 10-year averages and plotted on a graph [Reddy, 2000]. This showed a Sine Curve of 60 years. The first two 60-year cycles completed by 1985/86. The third cycle started in 1986/87 [starting year of Telugu 60 year calandar year — Prabhava]. IITM scientists selected the data series starting from the centre of the above average 30 year period and moved on to the lowest point of the below the average 30 year period. This naturally present a decreasing trend. If they would have selected 30 period prior to this, would have presented exactly opposite pattern [increasing trend]. This I brought to the notice of the minister concerned. Also, if the data series present not only principal cycle but also sub-multiples, the pattern could be different. For example Durban rainfall presents 66 year cycle with 22 year sub-multiple. After integrating these two cycles [using amplitude and phase angles with reference starting year] the pattern showed “W” [below the average] followed by “M” [above the average]. Similar situation was observed in Mahalypye in Botswana, Catuane in Mozambique and Fortaleza in Northeast Brazil.
If we come to US temperature and AMO: increasing trend of the 60-year cycle arm of Sine Curve started around 1980. Thus, the truncated data showed warmer conditions in summer and winter. If the authors would have selected 30 year period prior to 1980s, the conclusion will be different — opposite –. So, it is always better to use the data series of one full cycle [if any].
During drought period of natural variability in rainfall generally show higher temperatures. In addition these are modified by urban effect in the down side [advection]. Changes in greenery/forests, etc.
Dr. S. Jeevananda Reddy
All of which is irrelevant if there is not a specification on the response times on instruments when they are replaced and even half way to due care and attention to the measurement environment.