The Post-1998 Hiatus Plods On…Regionally
North America (180-0°N, 15-60°N) has been characterized as a “major cooling center” by the authors of a new paper (Gan et al., 2019) published in Earth and Space Science.
The continent warmed from 1982-1998, but a cooling trend since 1998 has nearly wiped out all the previous warming.
Overall, there has been no significant temperature change in North America since 1982.
The warming and cooling trends, especially the daily temperature minimum (Tmin), are well-correlated (r=0.71) with the path of the Atlantic Multidecadal Oscillation (AMO) during 1950-2014, leading the authors to conclude that the temperature trends over this 32-year period are “a result of” natural changes in the AMO.
The Key Role of Atlantic Multidecadal Oscillation in Minimum Temperature Over North America During Global Warming Slowdown
Daily Minimum temperature (Tmin) is an important variable in both global and regional climate changes, and its variability can greatly affect the ecological system. In the early 21st century, warming slowdown is seen over the North Hemisphere and North America is one of the major cooling centers.
In this study, we found that Tmin experienced an obvious decline in North America during warming slowdown period.
Such Tmin decline is closely related to the Atlantic Multidecadal Oscillation (AMO), the correlation between the decadal components of Tmin and AMO reached 0.71 during 1950-2014.
According to composite analysis, the AMO on the positive (negative) phase takes two low-pressure (high-pressure) systems in the northeastern Pacific and the North Atlantic at night, accompanied by cyclonic (anticyclonic) circulations and warm (cold) advection in North America.
Therefore, the analyses conclude that the Tmin decline during warming slowdown period is a result of the synchronous decrease of the AMO. The results emphasize the key role of AMO on the decadal variation of Tmin in North America.
Image Source: Gan et al., 2019
Another new paper renews the global warming “hiatus” debate and documents a 21st-century cooling trend in northern China that also effectively snuffs out the previous decades of warming for the region.
Satellite-based regional warming hiatus in China and its implication
Global warming ‘stalled’ or ‘paused’ for the period 1998–2012, as claimed by the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) (IPCC, 2013).
However, the early drafts of IPCC AR5 have no detailed explanation for this “hiatus” since 111 of 114 climate models in the CMIP5 earth system model did not verify this phenomenon. …
In 2017, after a wave of scientific publications and public debate, the climate models as reported in IPCC remain debates, including definitions of “hiatus” and datasets (Medhaug et al., 2017).
Image Source: Li et al., 2019
The slowdown in global warming since 1998, often termed the global warming hiatus. Reconciling the “hiatus” is a main focus in the 2013 climate change conference.
Accurately characterizing the spatiotemporal trends in surface air temperature (SAT) is helps to better understand the “hiatus” during the period. This article presents a satellite-based regional warming simulation to diagnose the “hiatus” for 2001–2015 in China.
Results show that the rapid warming is mainly in western and southern China, such as Yunnan (mean ± standard deviation: 0.39 ± 0.26 °C (10 yr)−1 ), Tibet (0.22 ± 0.25 °C (10 yr)−1), Taiwan (0.21 ± 0.25 °C (10 yr)−1), and Sichuan (0.19± 0.25 °C (10 yr)−1).
On the contrary, there is a cooling trend by 0.29 ± 0.26 °C (10 yr)−1 in northern China during the recent 15 yr, where a warming rate about 0.38 ± 0.11 °C (10 yr)−1 happened for 1960–2000. Overall, satellite simulation shows that the warming rate is reduced to −0.02 °C (10 yr)−1.
The changes in underlying surface, Earth’s orbit, solar radiation and atmospheric counter radiation (USEOSRACR) cause China’s temperature rise about 0.02 °C (10 yr)−1. A combination of greenhouse gases (GHGs) and other natural forcing (ONAT, predominately volcanic activity, and atmosphere and ocean circulation) explain another part of temperature trend by approximately −0.04 °C (10 yr)−1.
We conclude that there is a regional warming hiatus, a pause or a slowdown in China, and imply that GHGs-induced warming is suppressed by ONAT [other natural forcing] in the early 21st century.
Image Source: Li et al., 2019
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In a perfect world, people would give global warming /climate change a critical review. The “remedies” proposed to solve the “threat” are really a protection racket.
Everyone should ask themselves these questions : Did you sense or notice any trend in the weather over the last 25 years? (climate)
Has your perception been influenced by suggestion?
Answer honestly.
Sonnyhill, we respond to the activists because they are loud and put themselves in people’s faces. They also have political influence way out of proportion to their numbers. I believe that most people have actually followed your suggestion. That is why survey’s have shown that climate change is near the bottom of the issues Americans are concerned about. In some cases, climate change is so low it doesn’t even listed in the survey results.
Cooling they say ? OK but cooling caused by global warming right ?
It’s just not fair to screw with some peoples religion and big scary .
Wait till the full effect of no sun spots take hold .
The scam is in its death throes and these phony politicians can’t resist going to the scary global warming piggy bank one more time .
This time they aren’t just targeting coal workers they plan on wiping out
aviation , jobs and quality of life from fossil fuels , .
In two weeks they have given the finger to :
Jews
Unions and non union workers
Victims of illegal immigrant murders and rapists
Border security
the Deplorables … again
NY economy
Nancy Pelosi already looks exhausted from playing new Democrat wack a mole as the Trump hate continues to consume the old guard of the party .
And clearly the cooling is caused by “Climate Change” from CO2 emissions as their models told them. It’s clear as mud!
So, how can the claim that 2015 of warmer than 2014, 2016 of warmer than 2015, and 2017 of warmer than 2016 be true if we have cooling. That is where NOAA comes in. If the data doesn’t support the climate change movement, then change it so that it does.
I had an on line debate with a warmest who was claiming that the hiatus in cooling didn’t exist. I shut him down by pointing out that activists had come up with 64 excuses for the hiatus. If it didn’t exist why were so many environmentalist trying to explain it?
Yes changes are very apparent. There are increasingly number of sudden temperature shifts in any given season, Winter will now have several 60deg thaws within a context of 20 degree temperatures. Summer likewise extremes push warmer temps followed by colder and sudden storms. Rainfall is extreme, this is the first time in 60 years we have seen consistent and numerous gullies half a foot deep and a foot wide form from as little as a half hour downpour. Winter snows have become far more wet, typical inch of snow followed by sleet and then rain, consistently. Now a heavy dry snow is the exception. There are also sudden temp changes in april and may, frequent overnight frosts which have frozen blossoms and buds from trees and fruit trees.