Abstract

The relationship between leading atmospheric teleconnection patterns and Greenland Ice Sheet (GrIS) temperature, precipitation, and surface mass balance (SMB) are investigated for the last 36 summers (1979–2014) based on Modern-Era Retrospective analysis for Research and Applications version 2 reanalyses. The results indicate that the negative phase of both the North Atlantic Oscillation (NAO) and Arctic Oscillation, associated with warm and dry conditions for the GrIS, lead to SMB decreases within 0–1 months. Furthermore, the positive phase of the East Atlantic (EA) pattern often lags the negative NAO, reflecting a dynamical linkage between these modes that acts to further enhance the warm and dry conditions over the GrIS, leading to a favorable environment for enhanced surface mass loss. The development of a strong negative NAO in combination with a strong positive EA in recent years leads to significantly larger GrIS warming compared to when the negative NAO occurs in combination with a negative or weak positive EA (0.69 K versus 0.13 K anomaly). During 2009 and 2011, weakened (as compared to conditions during the severe surface melt cases of 2010 and 2012) local high pressure blocking produced colder northerly flow over the GrIS inhibiting warming despite the occurrence of a strong negative NAO, reflecting an important role for the EA during those years. In particular, the EA acts with the NAO to enhance warming in 2010 and 2012, and weaken high pressure blocking in 2009 and 2011. In general, high pressure blocking primarily impacts the western areas of the GrIS via advective temperature increases, while changes in net surface radiative fluxes account for both western and eastern GrIS temperature changes.

Details

Title
Atmospheric summer teleconnections and Greenland Ice Sheet surface mass variations: insights from MERRA-2
Author
Young-Kwon, Lim 1 ; Schubert, Siegfried D 2 ; Nowicki, Sophie M J 3 ; Lee, Jae N 4 ; Molod, Andrea M 5 ; Cullather, Richard I 5 ; Zhao, Bin 6 ; Velicogna, Isabella 7 

 Global Modeling and Assimilation Office, NASA/GSFC, Greenbelt, MD, USA; Goddard Earth Sciences Technology and Research/I. M. Systems Group, Greenland, MD, USA 
 Global Modeling and Assimilation Office, NASA/GSFC, Greenbelt, MD, USA 
 Cryospheric Sciences Laboratory, NASA/GSFC, Greenbelt, MD, USA 
 Climate and Radiation Laboratory, NASA/GSFC, Greenbelt, MD, USA; University of Maryland, Baltimore County, Baltimore, MD, USA 
 Global Modeling and Assimilation Office, NASA/GSFC, Greenbelt, MD, USA; Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD, USA 
 Global Modeling and Assimilation Office, NASA/GSFC, Greenbelt, MD, USA; Science Appications International Corporation, Greenbelt, MD, USA 
 Earth System Science, University of California, Irvine, CA, USA; Jet Propulsion Laboratory, CA, USA 
Publication year
2016
Publication date
Feb 2016
Publisher
IOP Publishing
e-ISSN
17489326
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2549219239
Copyright
© 2016. This work is published under http://creativecommons.org/licenses/by/3.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.