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Abstract. Understanding the role of atmospheric circulation anomalies on the surfacemass balance of the Greenland ice sheet (GrIS) is fundamental for improvingestimates of its current and future contributions to sea level rise. Here,we show, using a combination of remote sensing observations, regionalclimate model outputs, reanalysis data, and artificial neural networks, thatunprecedented atmospheric conditions (1948–2019) occurring in the summerof 2019 over Greenland promoted new record or close-to-record values ofsurfacemass balance (SMB), runoff, and snowfall. Specifically, runoff in 2019 ranked second withinthe 1948–2019 period (after 2012) and first in terms of surface massbalance negative anomaly for the hydrological year 1 September 2018–31 August 2019. The summer of 2019 was characterized by an exceptionalpersistence of anticyclonic conditions that, in conjunction with low albedoassociated with reduced snowfall in summer, enhanced the melt–albedofeedback by promoting the absorption of solar radiation and favoredadvection of warm, moist air along the western portion of the ice sheettowards the north, where the surface melt has been the highest since 1948.The analysis of the frequency of daily 500 hPa geopotential heights obtainedfrom artificial neural networks shows that the total number of days with thefive most frequent atmospheric patterns that characterized the summer of2019 was 5 standard deviations above the 1981–2010 mean, confirming theexceptional nature of the 2019 season over Greenland.
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Imaging subglacial hydrology beneath the Greenland Ice Sheet
We will deploy 36 3-component short period (1 Hz?) sensors for one summer, May-August 2019 on the Greenland Ice sheet at about 1000m elevation. Sensors will need to be installed on poles drilled into the ice due to melt out during the summer, similar to previous projects. Ideally these would be L2s with Q330s similar to the request we put in last year, but I am less clear on the frequency range of your new GeoIce equipment, perhaps that is also appropriate. We would like to preserve the 1-4 Hz band and not use 4.5 Hz sensors if possible. Instruments would need to be shipped in spring to make the air force flights up to Greenland. They would be pulled out in August and presumably back to PASSCAL by October sometime.
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- Award ID(s):
- 1838464
- PAR ID:
- 10561226
- Publisher / Repository:
- International Federation of Digital Seismograph Networks
- Date Published:
- Format(s):
- Medium: X Size: 600000 MB Other: SEED data
- Size(s):
- 600000 MB
- Location:
- (East Bound Longitude:-49.163; North Bound Latitude:72.554; South Bound Latitude:70.348; West Bound Longitude:-53.360)
- Sponsoring Org:
- National Science Foundation
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