Temperature anomalies are warming faster than Earth's average

Temperature anomalies are warming faster than Earth's average
The middle panel illustrates spatial patterns of temperature anomalies for April 1998. The top panel shows locations that are below the 25th percentile, and the bottom panel shows locations that are above the 75th percentile. Credit: Scott Robeson, Indiana University

It's widely known that the Earth's average temperature has been rising. But research by an Indiana University geographer and colleagues finds that spatial patterns of extreme temperature anomalies—readings well above or below the mean—are warming even faster than the overall average.

And trends in extreme heat and cold are important, said Scott M. Robeson, professor of geography in the College of Arts and Sciences at IU Bloomington. They have an outsized impact on water supplies, agricultural productivity and other factors related to human health and well-being.

"Average temperatures don't tell us everything we need to know about climate change," he said. "Arguably, these cold extremes and warm extremes are the most important factors for human society."

Robeson is the lead author of the article "Trends in hemispheric warm and cold anomalies," which will be published in the journal Geophysical Review Letters and is available online. Co-authors are Cort J. Willmott of the University of Delaware and Phil D. Jones of the University of East Anglia.

The researchers analyzed temperature records for the years 1881 to 2013 from HadCRUT4, a widely used data set for land and sea locations compiled by the University of East Anglia and the U.K. Met Office. Using monthly average temperatures at points across the globe, they sorted them into "spatial percentiles," which represent how unusual they are by their geographic size.

Their findings include:

  • Temperatures at the cold and warm "tails" of the spatial distribution—the 5th and 95th percentiles—increased more than the overall average Earth temperature.
  • Over the 130-year record, cold anomalies increased more than warm anomalies, resulting in an overall narrowing of the range of Earth's temperatures.
  • In the past 30 years, however, that pattern reversed, with warm anomalies increasing at a faster rate than cold anomalies.

"Earth's temperature was becoming more homogenous with time," Robeson said, "but now it's not."

The study records separate results for the Northern and Southern Hemispheres. Temperatures are considerably more volatile in the Northern Hemisphere, an expected result because there's considerably less land mass in the South to add complexity to weather systems.

The study also examined anomalies during the "pause" in global warming that scientists have observed since 1998. While a 16-year-period is too short a time to draw conclusions about trends, the researchers found that warming continued at most locations on the planet and during much of the year, but that warming was offset by strong cooling during winter months in the Northern Hemisphere.

"There really hasn't been a pause in global warming," Robeson said. "There's been a pause in Northern Hemisphere winter warming."

Co-author Jones of the University of East Anglia said the study provides scientists with better knowledge about what's taking place with the Earth's climate. "Improved understanding of the spatial patterns of change over the three periods studied are vital for understanding the causes of recent events," he said.

It may seem counterintuitive that global warming would be accompanied by colder winter weather at some locales. But Robeson said the observation aligns with theories about climate change, which hold that amplified warming in the Arctic region produces changes in the jet stream, which can result in extended periods of cold weather at some locations in the mid-northern latitudes.

And while the rate of planetary warming has slowed in the past 16 years, it hasn't stopped. The World Meteorological Organization announced this month that 2014 is on track to be one of the warmest, if not the warmest, years on record as measured by global average temperatures.

In the U.S., the East has been unusually cold and snowy in recent years, but much of the West has been unusually warm and has experienced drought. And what happens here doesn't necessarily reflect conditions on the rest of the planet. Robeson points out that the United States, including Alaska, makes up only 2 percent of the Earth's surface.


Explore further

Human influence important factor in possible global and UK temperature records

More information: "Trends in hemispheric warm and cold anomalies." Geophysical Research Letters DOI: 10.1002/2014GL062323
Journal information: Geophysical Research Letters

Provided by Indiana University
Citation: Temperature anomalies are warming faster than Earth's average (2014, December 9) retrieved 26 May 2019 from https://phys.org/news/2014-12-extreme-temperature-anomalies-faster-earth.html
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Dec 09, 2014
So there it is - the USA, with only 2 percent of the Earth's surface, cannot serve as the denier's proof that global warming is not occurring.

Dec 09, 2014
Hmmm, there are extreme local effects?
Where have you heard that before?

Oh, yeah, from me. I'll go ahead and cite this article, and continue in my long line of "I told ya so's."

Food for thought. They don't say what is causing the local effects, but something is causing them.

Dec 09, 2014
extreme temperature anomalies...are warming even faster than the overall average.

Yes, of course, but that's purely statistical information and doesn't mean anything. Then again, the global average temperature hasn't gone up for 16 to 26 years (depending on the statistical confidence level) so those warming extremes are currently being cancelled out by cooling extremes. Here's what HadCRUT4 shows:

http://www.cru.ue...RUT4.png

Notice the global trend line since 1998 is flat. Of course some areas warm more (and cool) more--and more rapidly--than others. There's nothing new about that. Those are the same regional effects that humans have been aware of for millennia that are associated with cold spells, warm spells, etc. To date, according to the latest IPCC report, there is little evidence of weather extremes increasing and thus no correlation to global warming.

It's interesting that the graphic is from 1998, the big El Niño year.

Dec 09, 2014
extreme temperature anomalies...are warming even faster than the overall average.


Yes, of course, but that's purely statistical information and doesn't mean anything. Then again, the global average temperature hasn't gone up for 16 to 26 years


From the article:

"And while the rate of planetary warming has slowed in the past 16 years, it hasn't stopped. The World Meteorological Organization announced this month that 2014 is on track to be one of the warmest, if not the warmest, years on record as measured by global average temperatures"

Do refrain from comment until you learn how to read.

Dec 10, 2014
Quoting from the article: "In the U.S., the East has been unusually cold and snowy in recent years, but much of the West has been unusually warm and has experienced drought."

Curious, but as I examine the images ( red = hot anomaly , blue = cool anomaly), I see quite the opposite.

Dec 10, 2014
Quoting from the article: "In the U.S., the East has been unusually cold and snowy in recent years, but much of the West has been unusually warm and has experienced drought."

Curious, but as I examine the images ( red = hot anomaly , blue = cool anomaly), I see quite the opposite.


This is why:
"The middle panel illustrates spatial patterns of temperature anomalies for April 1998"

Dec 14, 2014
Hmmm, there are extreme local effects?
Where have you heard that before?
@ALCHE/crybaby
well, it has been in at least 4 article links i have posted, as well as 2 studies and I study i recently linked to you to refute...

I guess you ARE reading some of the studies i left
Oh, yeah, from me. I'll go ahead and cite this article, and continue in my long line of "I told ya so's."
ok, maybe you are reading them and now trying to convince the suckers that it has ALWAYS been your own idea...
TOO BAD it is already in the studies i linked

ROTFLMFAO
i love how you actually gave the argument right here PROVING adn SUPPORTING the studies i've linked to you, but somehow it is all YOUR knowledge now!
ROTFLMFAO
http://sci-ence.o...-flags2/

Dec 14, 2014
Stumpy-GET THIS:
I ONLY SEE YOUR POSTS IF I GO TO THE SITE WITHOUT LOGGING ON.
YOUR POSTS. WHEN I HAVE READ THEM USE MIS-DIRECTION WHEN THEY AREN'T ACTUALLY IRRELEVANT.

Please stop using the fact I ignore you for cheap shots. It shows what you are.

Dec 14, 2014
GET THIS:
I ONLY SEE YOUR POSTS IF I GO TO THE SITE WITHOUT LOGGING ON.
YOUR POSTS. WHEN I HAVE READ THEM USE MIS-DIRECTION WHEN THEY AREN'T ACTUALLY IRRELEVANT.

Please stop using the fact I ignore you for cheap shots. It shows what you are.
@ALCHE/Crybaby
crying about being outed AGAIN?

I don't give you cheap shots... i simply keep reminding everyone else about the PSEUDOSCIENCE that you continually post with regard to climate science, and how you have been proven wrong ans well as how you IGNORE the science for your own personal faith in waterbowls

THIS is not cheap shots, this is REMINDING people of who you REALLY are and reminding them of how you've suckered them in the past

AND IT WORKS, because i've noticed that you've been caught in other lies by other posters

THANKS for listening guys

REGARDLESS of the poster
FOLLOW THE SCIENCE
forget about politics

http://marine.rut..._pub.pdf

Dec 14, 2014
Let me guess, another book-long irrelevant rant against poor me?

Dec 21, 2014
Elsewhere Water_Prophet claimed
They show everything you need to know about why CO2 doesn't work
That is ONLY from Sol to Earth, U miss SO MUCH !

WHY Water_Prophet do U REFUSE to look at absorption/re-radiation of Earth to Space ?

You seem to have a very serious reading/comprehension neglect bias problem !

Please FOCUS on these SIMPLE questions, do U accept:-

1. Your TSI graph ONLY shows Sol to Earth - largely Shortwave (SW) ?

2. Earth converts SW to Longwave radiation (LW) ?

3. Negligible SW is emitted to space ?

SIMPLE logic by way of SUBTRACTION re energy PROVES LW to space is CORE issue !
.
.
.
Water_Prophet, these is a VERY simple issue, WHY do U ignore it & look intellectually feeble ?

Please be GENUINE & smarter & not come across with some form of disability... :-(

I await the clarity of response a REAL Physical Chemist (PC) can actually muster to this link:-
http://phys.org/n...day.html

Dec 25, 2014
Elsewhere Water_Prophet expounded by showing us example of Hypocrisy
The biggest problem is from pretenders or people with no education who spout their opinions out, which is fine, but then deny even when they do not know, and of course are uninterested in learning or even considering a fact that contradicts their opinion
Agree fully with that pattern.

Your opinion Water_Prophet that CO2 is not significant re TSI is correct, agree with You :-)

People who graduated as a Physical Chemist (PC) of which Water_Prophet claims, should KNOW energy flows in 3D, so Y do U completely IGNORE Earth's emissions which any person with intelligence & Physics training easily determine it MUST be overwhelmingly Long Wave (LW) ie. Plain to "see" Short Wave (SW) from Earth is negligible !

Why do You ignore LW, where CO2's absorbance/re-radiation is the HIGHEST ?

Water_Prophet muttered
..having only a fork's understanding of how the food tastes
What does this even mean?

Dec 26, 2014
Elsewhere Water_Prophet claimed
How can you say I ignore longwave radiations?
By evidence U ignored long wave (LW) radiation re CO2's interference to space, U only saw TSI.

U write fossil fuel (FF) proportion of TSI, yet U IGNORE FACT Earth converts short wave (SW) to LW & CO2 interferes with emission to Space. Nobody is disagreeing FF adds heat & CO2. But, U, as a claimed Physical Chemist (PC) haven't acknowledged CO2's interference U even claimed "CO2 is a red herring", which is obviously completely WRONG !

Water_Prophet claimed
..1998 was a very hot year; Industry was booming and the Sun was at/near a max
Huh? U claim Sun TSI was at max ? Not according to this
http://www.skepti...asic.gif

Water_Prophet claimed to be a PC, yet doesn't write like one, does Water_Prophet accept:-

1. TSI mainly SW
2. Earth converts SW to LW
3. LW to space interfered by CO2

Simple issue Water_Prophet I asked before, WHY do u STILL evade ?

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