Greenland Ice Sheet: High-elevation balance and peripheral thinning

Science

Volumn 289, Issue 5478, 2000, Pages 428-430

  Krabill, W ^a   Abdalati, W ^a   Frederick, E ^b   Manizade, S ^b   Martin, C ^b   Sonntag, J ^b   Swift, R ^b   Thomas, R ^b   Wright, W ^a   Yungel, J ^b  

^a NASA GODDARD SPACE FLIGHT CENTER   (United States)

^b EG&G   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ELEVATION; ICE SHEET; MASS BALANCE;

ARTICLE; CLIMATE; ENVIRONMENTAL MONITORING; GEOGRAPHY; GREENLAND; PRIORITY JOURNAL;

GREENLAND;

EID: 0034698208     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.289.5478.428     Document Type: Article

References (18)

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2. 0.5 cm, where N is the number of flight lines over the region. Nearer the coast, spatial variability increases and interpolation errors can predominate. Errors that are systematic to an entire year's survey are caused mainly by uncertainty (of about 1 cm) in the location of GPS base stations, introducing a possible bias to estimates of dH/dt of 0.3 cm/year.
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9. L. Toudal Pedersen, personal communication. The polynya size was calculated using passive microwave-derived ice concentration data.
10. PDD anomalies were calculated using 6-hourly temperature data dating back to 1979 from coastal stations around the perimeter of Greenland. Of the 54 stations in the data set, the 13 shown in Fig. 1 had values for at least 15 of the last 20 years, and for all five of the years that separate the surveys. Anomalies were calculated by subtracting the mean PDD for the full record from that for the 5-year period between surveys.
11. The PDD ablation factors used are 3 mm water/ PDD for snow and 8 mm water/PDD for ice [R. J. Braithwaite, J. Glaciol. 41, 153 (1995)]. After adjusting for density, each of these numbers corresponds to an elevation change of 9 mm/PDD.
12. 3/year volume change (75% of the total). The true volume change in this area is likely to be greater.
13. R. Warrick, C. Le Provost, M. Meier, J. Oerlemans, P. Woodwortn, in Climate Change, 1995; The Science of Climate Change (Cambridge Univ. Press, Cambridge, 1996), pp. 359-405.
14. Temperature records were decoded by the National Center for Environmental Prediction and were obtained from the National Center for Atmospheric Research.
15. M. M. Herron, S. L. Herron, C. C. Langway, Nature 293, 389 (1981).
16. A temperature record for 1900-95 was calculated using data from the NOAA National Climate Diagnostic Center accessible at http://www.ncdc.noaa. gov/onlineprod/ghcnmcdwseasonal/form.html. Quality control procedures are described in J. K. Eischeid et al. [J. Appl. Meteorol. 34, 2787 (1995)].
17. A. Weidick, Rapp. Gronlands Geol. Unders. 152, 73 (1991).
18. We thank the crew of the NASA P-3 aircraft used for the Greenland surveys. We acknowledge the technical support of R. Mitchell, A. Waller, and J. Scott. This work was supported by NASA's Polar Research Program and the ICESAT Project.