Skip to main content
Menu

Main navigation

  • About
    • Annual Reports
    • Leadership
    • Jobs
    • Student Programs
    • Media Information
    • Store
    • Contact
    LOADING...
  • Experts
    • Policy Scholars
    • Adjunct Scholars
    • Fellows
  • Events
    • Upcoming
    • Past
    • Event FAQs
    • Sphere Summit
    LOADING...
  • Publications
    • Studies
    • Commentary
    • Books
    • Reviews and Journals
    • Public Filings
    LOADING...
  • Blog
  • Donate
    • Sponsorship Benefits
    • Ways to Give
    • Planned Giving

Issues

  • Constitution and Law
    • Constitutional Law
    • Criminal Justice
    • Free Speech and Civil Liberties
  • Economics
    • Banking and Finance
    • Monetary Policy
    • Regulation
    • Tax and Budget Policy
  • Politics and Society
    • Education
    • Government and Politics
    • Health Care
    • Poverty and Social Welfare
    • Technology and Privacy
  • International
    • Defense and Foreign Policy
    • Global Freedom
    • Immigration
    • Trade Policy
Live Now

Cato at Liberty


  • Blog Home
  • RSS

Email Signup

Sign up to have blog posts delivered straight to your inbox!

Topics
  • Banking and Finance
  • Constitutional Law
  • Criminal Justice
  • Defense and Foreign Policy
  • Education
  • Free Speech and Civil Liberties
  • Global Freedom
  • Government and Politics
  • Health Care
  • Immigration
  • Monetary Policy
  • Poverty and Social Welfare
  • Regulation
  • Tax and Budget Policy
  • Technology and Privacy
  • Trade Policy
Archives
  • April 2021
  • March 2021
  • February 2021
  • January 2021
  • December 2020
  • November 2020
  • October 2020
  • September 2020
  • August 2020
  • July 2020
  • June 2020
  • May 2020
  • April 2020
  • March 2020
  • February 2020
  • January 2020
  • December 2019
  • November 2019
  • October 2019
  • September 2019
  • August 2019
  • July 2019
  • June 2019
  • May 2019
  • April 2019
  • March 2019
  • February 2019
  • January 2019
  • December 2018
  • November 2018
  • October 2018
  • September 2018
  • August 2018
  • July 2018
  • June 2018
  • May 2018
  • April 2018
  • March 2018
  • February 2018
  • January 2018
  • December 2017
  • November 2017
  • October 2017
  • September 2017
  • August 2017
  • July 2017
  • June 2017
  • May 2017
  • April 2017
  • March 2017
  • February 2017
  • January 2017
  • December 2016
  • November 2016
  • October 2016
  • September 2016
  • August 2016
  • July 2016
  • June 2016
  • May 2016
  • April 2016
  • March 2016
  • February 2016
  • January 2016
  • December 2015
  • November 2015
  • October 2015
  • September 2015
  • August 2015
  • July 2015
  • June 2015
  • May 2015
  • April 2015
  • March 2015
  • February 2015
  • January 2015
  • December 2014
  • November 2014
  • October 2014
  • September 2014
  • August 2014
  • July 2014
  • June 2014
  • May 2014
  • April 2014
  • March 2014
  • February 2014
  • January 2014
  • December 2013
  • November 2013
  • October 2013
  • September 2013
  • August 2013
  • July 2013
  • June 2013
  • May 2013
  • April 2013
  • March 2013
  • February 2013
  • January 2013
  • December 2012
  • November 2012
  • October 2012
  • September 2012
  • August 2012
  • July 2012
  • June 2012
  • May 2012
  • April 2012
  • March 2012
  • February 2012
  • January 2012
  • December 2011
  • November 2011
  • October 2011
  • September 2011
  • August 2011
  • July 2011
  • June 2011
  • May 2011
  • April 2011
  • March 2011
  • February 2011
  • January 2011
  • December 2010
  • November 2010
  • October 2010
  • September 2010
  • August 2010
  • July 2010
  • June 2010
  • May 2010
  • April 2010
  • March 2010
  • February 2010
  • January 2010
  • December 2009
  • November 2009
  • October 2009
  • September 2009
  • August 2009
  • July 2009
  • June 2009
  • May 2009
  • April 2009
  • March 2009
  • February 2009
  • January 2009
  • December 2008
  • November 2008
  • October 2008
  • September 2008
  • August 2008
  • July 2008
  • June 2008
  • May 2008
  • April 2008
  • March 2008
  • February 2008
  • January 2008
  • December 2007
  • November 2007
  • October 2007
  • September 2007
  • August 2007
  • July 2007
  • June 2007
  • May 2007
  • April 2007
  • March 2007
  • February 2007
  • January 2007
  • December 2006
  • November 2006
  • October 2006
  • September 2006
  • August 2006
  • July 2006
  • June 2006
  • May 2006
  • April 2006
  • Show More
June 10, 2016 10:10AM

Taming the Greenland Melting Global Warming Hype

By Patrick J. Michaels and Paul C. "Chip" Knappenberger

SHARE

Global Science Report is a feature from the Center for the Study of Science, where we highlight one or two important new items in the scientific literature or the popular media. For broader and more technical perspectives, consult our monthly “Current Wisdom.”


—


There is a new paper generating some press attention (e.g. Chris Mooney at the Washington Post) that strongly suggests global warming is leading to specific changes in the atmospheric circulation over the Northern Hemisphere that is causing an enhancement of surface melting across Greenland—and of course, that this mechanism will make things even worse than expected into the future.


We are here to strongly suggest this is not the case.


The new paper is by a team of authors led by Marco Tedesco from Columbia University’s Lamont‐​Doherty Earth Observatory. The main gist of the paper is that Arctic sea ice loss as a result of human‐​caused global warming is causing the jet stream to slow down and become wigglier—with deeper north‐​south excursions that hang around longer. This type of behavior is referred to as atmospheric “blocking.”


If this sounds familiar, it’s the same theoretical argument that is made to try to link wintertime “polar vortex” events (i.e., cold outbreaks) and blizzards to global warming. This argument which has been pretty well debunked, time and time again.


Well, at least it has as it concerns wintertime climate.


The twist of the new Tedesco and colleagues’ paper is that they’ve applied it to the summertime climate over Greenland. They argue that global warming is leading to an increase in blocking events over Greenland in the summer and that is causing warm air to be “locked” in place leading to enhanced surface melting there. Chris Mooney, who likes to promote climate alarm buzzwords, refers to this behavior as “weird.” And he describes the worrysome implications:

The key issue, then, is whether 2015 is a harbinger of a future in which the jet stream keeps sending Greenland atmospheric systems that drive major melt — and in turn, whether the Arctic amplification of climate change is driving this. If so, that could be a factor, not currently included in many climate change simulations, that would worsen the ice sheet’s melt, drive additional sea level rise and perhaps upend ocean currents due to large influxes of fresh water.

As proof that things were weird over Greenland in recent summers, Tedesco’s team offers up this figure in their paper:

Media Name: greenlandagain.png

<--break->


This chart (part of a multipanel figure) shows the time history of the North Atlantic Oscillation (NAO—a pattern of atmospheric variation over the North Atlantic) as red bars and something called the Greenland Blocking Index (GBI) as the black line, for the month of July during the period 1950–2015. The chart is meant to show that in recent years, the NAO has been very low with 2015 being “a new record low of -1.23 (since 1899),” and the GBI has been very high with the authors noting that “[c]oncurrently, the GBI also set a new record for the month of July [2015].” Clearly the evidence is showing that atmospheric blocking increasing over Greenland which fits nicely into the global warming/​sea ice loss/​wiggly jet stream theory.


So what’s our beef?


A couple of months ago, some of the same authors of the Tedesco paper (notably Ed Hanna) published a paper showing the history of the monthly GBI going back to 1851 (as opposed to 1950 as depicted in the Tedesco paper).


Here’s their GBI plotted for the month of July from 1851 to 2015:

Media Name: greenlanddoubleagain.jpg

This picture tells a completely different story. Instead of a long‐​term trend that could be related to anthropogenic global warming, what we see is large annual and multidecadal variability, with the end of the record not looking much different than say a period around 1880 and with the highest GBI occurring in 1918 (with 1919 coming in 2nd place). While this doesn’t conclusively demonstrate that the current rise in GBI is not related to jet stream changes induced by sea ice loss, it most certainly does demonstrate that global‐​warming induced sea ice loss is not a requirement for blocking events to occur over Greenland and that recent events are not at all “weird.” An equally plausible, if not much more plausible, expectation of future behavior is that this GBI highstand is part of multidecadal natural variability and will soon relax back towards normal values. But such an explanation isn’t Post‐​worthy.


Another big problem with all the new hype is that history shows the current goings‐​on in Greenland to be irrelevant, because humans just can’t make it warm enough up there to melt all that much ice. For example, in 2013, Dorthe Dahl‐​Jensen and her colleagues published a paper in Nature detailing the history of the ice in Northwest Greenland during the beginning of the last interglacial, which included a 6,000 year period in which her ice core data showed averaged a whopping 6⁰C warmer in summer than the 20th century average. Greenland only lost around 30% of its ice with a heat load of (6 X 6000) 36,000 degree‐​summers. The best humans could ever hope to do with greenhouse gases is—very liberally—about 5 degrees for 500 summers, or (5 X 500) 2,500 degree‐​summers. In other words, the best we can do is 500/6000 times 30%, or a 2.5% of the ice, resulting in a grand total of seven inches of sea level rise over 500 years. That’s pretty much the death of the Greenland disaster story, despite every lame press release and hyped “news” article on it.


While you won’t find this kind of analysis elsewhere, we’re happy to do it here at Cato. 


References:


Dahl‐​Jensen, D., et al., 2013. Eemian interglacial reconstructed from a Greenland folded ice core. Nature 489, doi: 10.1038/nature11789.


Hanna, E., et al., 2016. Greenland Blocking Index 1851–2015: a regional climate change signal. International Journal of Climatology, doi: 10.1002/joc.4673.


Tedesco, M., et al., 2016. Arctic cut‐​off high drives the poleward shift of a new Greenland melting record. Nature Communications, DOI: 10.1038/ncomms11723, http://​www​.nature​.com/​n​c​o​m​m​s​/​2​0​1​6​/​1​6​0​6​0​9​/​n​c​o​m​m​s​1​1​7​2​3​/​f​u​l​l​/​n​c​o​m​m​s​1​1​7​2​3​.html

Related Tags
Energy and Environment

Stay Connected to Cato

Sign up for the newsletter to receive periodic updates on Cato research, events, and publications.

View All Newsletters

1000 Massachusetts Ave. NW
Washington, DC 20001-5403
202-842-0200
Contact Us
Privacy

Footer 1

  • About
    • Annual Reports
    • Leadership
    • Jobs
    • Student Programs
    • Media Information
    • Store
    • Contact
  • Podcasts

Footer 2

  • Experts
    • Policy Scholars
    • Adjunct Scholars
    • Fellows
  • Events
    • Upcoming
    • Past
    • Event FAQs
    • Sphere Summit

Footer 3

  • Publications
    • Books
    • Cato Journal
    • Regulation
    • Cato Policy Report
    • Cato Supreme Court Review
    • Cato’s Letter
    • Human Freedom Index
    • Economic Freedom of the World
    • Cato Handbook for Policymakers

Footer 4

  • Blog
  • Donate
    • Sponsorship Benefits
    • Ways to Give
    • Planned Giving
Also from Cato Institute:
Libertarianism.org
|
Humanprogress.org
|
Downsizinggovernment.org