UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Atmospheric drivers of Greenland surface melt revealed by self-organizing maps

Mioduszewski, JR; Rennermalm, AK; Hammann, A; Tedesco, M; Noble, EU; Stroeve, JC; Mote, TL; (2016) Atmospheric drivers of Greenland surface melt revealed by self-organizing maps. Journal of Geophysical Research: Atmospheres , 121 (10) pp. 5095-5114. 10.1002/2015JD024550. Green open access

[thumbnail of Stroeve_atmospheric_greenland aam.pdf]
Preview
Text
Stroeve_atmospheric_greenland aam.pdf - Accepted version

Download (3MB) | Preview

Abstract

Recent acceleration in surface melt on the Greenland ice sheet (GrIS) has occurred concurrently with a rapidly warming Arctic and has been connected to persistent, anomalous atmospheric circulation patterns over Greenland. To identify synoptic setups favoring enhanced GrIS surface melt and their decadal changes, we develop a summer Arctic synoptic climatology by employing self-organizing maps. These are applied to daily 500 hPa geopotential height fields obtained from the Modern Era Retrospective Analysis for Research and Applications reanalysis, 1979–2014. Particular circulation regimes are related to meteorological conditions and GrIS surface melt estimated with outputs from the Modèle Atmosphérique Régional. Our results demonstrate that the largest positive melt anomalies occur in concert with positive height anomalies near Greenland associated with wind, temperature, and humidity patterns indicative of strong meridional transport of heat and moisture. We find an increased frequency in a 500 hPa ridge over Greenland coinciding with a 63% increase in GrIS melt between the 1979–1988 and 2005–2014 periods, with 75.0% of surface melt changes attributed to thermodynamics, 17% to dynamics, and 8.0% to a combination. We also confirm that the 2007–2012 time period has the largest dynamic forcing relative of any period but also demonstrate that increased surface energy fluxes, temperature, and moisture separate from dynamic changes contributed more to melt even during this period. This implies that GrIS surface melt is likely to continue to increase in response to an ever warmer future Arctic, regardless of future atmospheric circulation patterns.

Type: Article
Title: Atmospheric drivers of Greenland surface melt revealed by self-organizing maps
Open access status: An open access version is available from UCL Discovery
DOI: 10.1002/2015JD024550
Publisher version: http://doi.org/10.1002/2015JD024550
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
Keywords: Greenland ice sheet; synoptic climatology; attribution; self-organizing maps; energy balance
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Earth Sciences
URI: https://discovery.ucl.ac.uk/id/eprint/1520431
Downloads since deposit
68Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item