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Wang, Wenshan

Publications and source records attributed to Wang, Wenshan.

3 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Wind‐Associated Melt Trends and Contrasts Between the Greenland and Antarctic Ice Sheets

Föhn and katabatic winds (downslope winds) can increase ice sheet surface melt, run-off, and ice-shelf vulnerability to hydrofracture and are poorly constrained on the Greenland and Antarctic ice sheets (GIS and AIS). We use regional climate model simulations of the GIS and AIS to quantify and intercompare trends in downslope winds and associated melt since 1960. Results reveal surface melt associated with downslope wind is significant on both the GIS and AIS representing 27.5 ± 4.5% and 19.7 ± 3.8% of total surface melt respectively. Wind-associated melt has decreased 31.8 ± 5.3% on the AIS while total melt decreased 15.4 ± 2.4% due to decreased föhn-induced melt on the Antarctic Peninsula and increasing stratospheric ozone. Wind-associated melt has increased 10.3 ± 2.5% on the GIS, combining with a more positive North Atlantic Oscillation and warmer surface to increase total melt 34 ± 5.8%.

58 GEOSCIENCES↗
DOE OSTI2021

Greenland Surface Melt Dominated by Solar and Sensible Heating

The Greenland Ice Sheet is the primary source of global Barystatic sea-level rise, and at least half of its recent mass-loss acceleration is caused by surface meltwater runoff. Previous studies on surface melt have examined various thermodynamic and dynamic drivers, yet their contributions are not compared using unified observations. We use decade-long in-situ measurements from automatic weather stations throughout the ablation zone to assess energy components and identify the leading physical processes in this area. Large melt events exceeding 3σ contribute only ~2% to total surface melt since 2007. The day-to-day variability of all melt is dominated by sensible heat exchange (31 ± 7%) and shortwave radiation (28 ± 5%). Sensible and solar heating correlate with the occurrence of dry and fast gravity-driven winds. These katabatic winds increase sensible heating of the surface mainly by enhancing vertical mixing that reduces the temperature inversion. The concomitant low humidity and clear skies yield increased solar heating.

54 ENVIRONMENTAL SCIENCES↗