A new study (Hanna et al., 2021) affirms a significant warming trend occurred in the late 20th century across Greenland, mirroring the warming that occurred in the early 20th century. Since 2001, the temperature trends across Greenland have stopped rising and begun cooling.
A temperature pattern has been emerging in Greenland during the last few decades that does not align with alarming proclamations of catastrophic ice sheet melt from accelerated warming.
After significant summer (winter) warming of about 2°C (to 4°C) from the 1980s to 2000, Greenland’s warming trend has plateaued and, since 2012, a cooling trend has commenced.
“[S]ince 2001 overall temperature trends are generally flat and insignificant due to a cooling pattern over the last 6–7 years.”
“According to MAR, and in line with the DMI coastal station analysis above, much of southern and southwest Greenland has not warmed during autumn since 1991. MAR trends between 2001 and 2019 show the southwest of the country cooling in winter and spring, and deeper, much more widespread cooling in west Greenland in autumn.”
Image Source: Hanna et al., 2021
Greenland’s Climate History Recycled
The temperature trends across Greenland seem to have followed an oscillatory pattern over the last 100 years. Between 1920 and 1930, Greenland abruptly warmed “between 2 and 4°C in less than ten years,” with some stations recording as much as 6°C warming during this span (Chylek et al., 2004).
Interestingly, Greenland’s “annual whole ice sheet 1919–32 warming trend [was] 33% greater in magnitude than the 1994–2007 warming” (Box et al., 2009).
Greenland temperatures plateaued during the 1930s and then, after 1940, a 50-year-long cooling trend commenced (Chylek et al., 2004).
Image Source: Chylek et al., 2004
Dubious CO2-Induced Greenland Warming
For some reason, Hanna and colleagues believe it is reasonable to assume CO2 has been driving the recent (1981-2000) warming even though they acknowledge CO2 has continued rising even as temperatures have flattened and cooled this century. They oddly project dramatic warming and ice sheet melt for the coming decades based on CO2 emissions scenarios.
Apparently these scientists are unaware of the measurements indicating the CO2 greenhouse effect forcing is as “comparatively weak” for Greenland as it is for Antarctica (-2.9 W/m² to +1 W/m²) according to Schmithusen et al. (2015), effectively ruling out a significant or even causal role for CO2 forcing of Greenland’s climate trends.
8 responses to “It’s Official: Greenland Has Not Warmed Since 2001: The Recent Sharp Warming Lasted From 1981-2000”
[…] It’s Official: Greenland Has Not Warmed Since 2001: The Recent Sharp Warming Lasted From 1981-2000 […]
So the warming petered out as The Pause (1997 – 2018?) started.
Their position on future CO2-driven warming actually helps the credibility of this paper to…disprove CO2-driven warming!
Because whereas their future estimate is just that, an estimate, their reconstruction of the past is based on empirical observations.
One is real, the other, well we’ll just have to wait and see.
For now, the message is clear; during the period of the greatest human CO2 emissions in history there’s been NO warming these past 20-odd years.
What does that say about ‘CO2-driven warming’?
Truth is so rare these days, but oh so refreshing!
Nowadays ice ages are referred to as “glaciations”, apparently because we now recognize that we’ve been experiencing an overall cooling over the past 65 million years.
Over the past 1.3 million years there have been 13 glaciations, average duration 90,000 years. Each glaciation was followed by a warming (an interglacial period), average duration 10,000 years.
Google “Post- Glacial Sea Level Rise” or “sea level graph covering past 12,000 years”: I can’t figure out how to get the graph directly into this comment.
This graph clearly reflects what transpires during an interglacial period. Also notice the graph covers 400+ feet of sea level rise since the last glaciation ended. About 6,000 years ago the rate of increase in sea level began to drop, and that has continued since. Our current rate of increase in sea level is a minuscule 1 to 3 mm per year. Almost the entire 400+ feet of increase was obviously brought on naturally. During the past few decades, during which some folks have become alarmed, the total rise in sea level rise has involved no more than the last few inches.
But wait, there’s more. Sun activity has recently dropped considerably. Sun activity drives both warming and cooling during the past 800,000 years according to Don Easterbrook (geologist). “The Solar Magnetic Cause of Climate Changes and Origin of the Ice Ages”. John Casey also talks about sun influence in “Dark Winter”.
Henrick Svensmark, Danish physicist, claimed, back in the 90s, how sun influence works. Cosmic rays entering the lower atmosphere contribute to the level of cloud formation. While there is pretty much a steady stream of cosmic rays, the strength of the sun’s magnetic field presents a “shield” during periods when sun activity is high and that reduces the level of cosmic rays which otherwise gain entry into the lower atmosphere. (CERN has long since validated Svensmark’s theory.) Low sun activity leads to more cosmic ray entry, hence more cloud cover, which reduces the amount of sun radiation reaching the earth’s surface.
Easterbrook’s stand-alone data strengthens Svensmark’s theory but is not dependent on its validity. Average cloud cover is beginning to have some impact on our global temperature. The temperature for February was the lowest in the past four decades.
What about CO2 increase causing global warming? There is no evidence that CO2 level has ever had any impact on our global temperature. What’s more, the actual warming projected by the computer models of proponents of human-caused warming involves an assumption that water vapor feedback is the real culprit, causing 2 to 3 times the warming supposedly brought on by CO2 increase. However, that assumption depends upon the validity of the greenhouse gas theory when applied to the open atmosphere. The GHG theory, to be applicable to the open atmosphere, must, at a minimum, also bring on a warming region about 10km above the tropics. Despite decades of radiosondes the hot spot in that region has never been found. The proponents of warming have defended themselves by providing more speculation as assumptions as to where that “hot spot” has gone.
In any case, take a harder look at that post-glacial map. It appears that we can assume from that graph that it represents almost the entire sea level cycle during this interglacial period. Now consider that during the past 13 glaciations (each earlier referred to as an “ice age”) have each, on average, lasted 90,000 years. Between each glaciation there has been a warming period (such as we have experienced for the past 10,000+ years), average duration 10,000 years. What do you think will happen next?
But there’s more. Sun activity recently dropped to its minimum. Such periods, if of significant duration, generally bring on a cooling period. Easterbrook (geologist) has a study (“The Solar Maganetic Cause of Climate Changes and Origin of the Ice Ages”) published as a book and available via Amazon. Easterbrook claims that the standalone data indicates that every warming and / or cooling is related to whether sun activity has been high or low.
Henrik Svensmark (Danish physicist) proposed a theory back in the late 90s that cosmic rays entering the lower atmosphere contribute to cloud cover. Cloud cover varies because during periods when the sun is active it provides a “shield” which obstructs some of the cosmic rays which would otherwise enter the lower atmosphere.
Conclusions drawn from the sea level graph plus the current low solar activity both indicate that we should expect either a serious cooling or the onset of our next glaciation. The former may cause serious problems for humanity, the latter will undoubtedly result in a catastrophe.
Since about 2007 I’ve been telling everyone that I noticed a change in jet stream behaviour around 2000.
Increased jet stream meridionality is associated with a less active sun and a cooling world.
My mechanism differs from the cosmic ray hypothesis of Svensmark but does affect global cloudiness and albedo because a more meridional jet stream results in longer lines of air mass mixing and greater cloudiness.
More clouds leads to less solar energy into the oceans and an increase in cold La Nina events relative to warm El Nino events.
It is looking like I was correct.
I don’t think Svensmark has it right:
[…] Kenneth Richard tar upp detta på NoTricksZone. Han uttrycker en förvåning över artikelförfattarnas slutsatser när de trots sina egna data påstår att det är CO2 som står bakom temperaturutvecklingen på Grönland: […]