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Title: Evaluation of Greenland near surface air temperature datasets

Abstract

Near-surface air temperature (SAT) over Greenland has important effects on mass balance of the ice sheet, but it is unclear which SAT datasets are reliable in the region. Here extensive in situ SAT measurements ( ∼  1400 station-years) are used to assess monthly mean SAT from seven global reanalysis datasets, five gridded SAT analyses, one satellite retrieval and three dynamically downscaled reanalyses. Strengths and weaknesses of these products are identified, and their biases are found to vary by season and glaciological regime. MERRA2 reanalysis overall performs best with mean absolute error less than 2 °C in all months. Ice sheet-average annual mean SAT from different datasets are highly correlated in recent decades, but their 1901–2000 trends differ even in sign. Compared with the MERRA2 climatology combined with gridded SAT analysis anomalies, thirty-one earth system model historical runs from the CMIP5 archive reach  ∼  5 °C for the 1901–2000 average bias and have opposite trends for a number of sub-periods.

Authors:
ORCiD logo;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1367939
Grant/Contract Number:
SC0016533
Resource Type:
Journal Article: Published Article
Journal Name:
The Cryosphere (Online)
Additional Journal Information:
Journal Name: The Cryosphere (Online); Journal Volume: 11; Journal Issue: 4; Related Information: CHORUS Timestamp: 2017-07-05 06:19:46; Journal ID: ISSN 1994-0424
Publisher:
Copernicus GmbH
Country of Publication:
Germany
Language:
English

Citation Formats

Reeves Eyre, J. E. Jack, and Zeng, Xubin. Evaluation of Greenland near surface air temperature datasets. Germany: N. p., 2017. Web. doi:10.5194/tc-11-1591-2017.
Reeves Eyre, J. E. Jack, & Zeng, Xubin. Evaluation of Greenland near surface air temperature datasets. Germany. doi:10.5194/tc-11-1591-2017.
Reeves Eyre, J. E. Jack, and Zeng, Xubin. 2017. "Evaluation of Greenland near surface air temperature datasets". Germany. doi:10.5194/tc-11-1591-2017.
@article{osti_1367939,
title = {Evaluation of Greenland near surface air temperature datasets},
author = {Reeves Eyre, J. E. Jack and Zeng, Xubin},
abstractNote = {Near-surface air temperature (SAT) over Greenland has important effects on mass balance of the ice sheet, but it is unclear which SAT datasets are reliable in the region. Here extensive in situ SAT measurements ( ∼  1400 station-years) are used to assess monthly mean SAT from seven global reanalysis datasets, five gridded SAT analyses, one satellite retrieval and three dynamically downscaled reanalyses. Strengths and weaknesses of these products are identified, and their biases are found to vary by season and glaciological regime. MERRA2 reanalysis overall performs best with mean absolute error less than 2 °C in all months. Ice sheet-average annual mean SAT from different datasets are highly correlated in recent decades, but their 1901–2000 trends differ even in sign. Compared with the MERRA2 climatology combined with gridded SAT analysis anomalies, thirty-one earth system model historical runs from the CMIP5 archive reach  ∼  5 °C for the 1901–2000 average bias and have opposite trends for a number of sub-periods.},
doi = {10.5194/tc-11-1591-2017},
journal = {The Cryosphere (Online)},
number = 4,
volume = 11,
place = {Germany},
year = 2017,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.5194/tc-11-1591-2017

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