Validation of a Climate-Data Record of the "Clear-Kky" Surface Temperature of the Greenland Ice Sheet
Surface temperatures on the Greenland Ice Sheet have been studied on the ground, using automatic weather station (AWS) data from the Greenland-Climate Network (GC-Net), and from analysis of satellite sensor data. Using Advanced Very High Frequency Radiometer (AVHRR) weekly surface temperature maps,...
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ftnasantrs:oai:casi.ntrs.nasa.gov:20110013378 2023-05-15T16:26:35+02:00 Validation of a Climate-Data Record of the "Clear-Kky" Surface Temperature of the Greenland Ice Sheet Hall, Dorothy K. DiGirolamo, Nicolo E. Comiso, Josefino C. Shuman, Christopher A. Koenig, Lora S. Box, Jason E. Unclassified, Unlimited, Publicly available [2011] application/pdf http://hdl.handle.net/2060/20110013378 unknown Document ID: 20110013378 http://hdl.handle.net/2060/20110013378 Copyright, Distribution as joint owner in the copyright CASI Meteorology and Climatology GSFC.CPR.4501.2011 Open Science Conference 2011; 24-28 Oct. 2011; Denver, CO; United States 2011 ftnasantrs 2019-07-21T01:01:55Z Surface temperatures on the Greenland Ice Sheet have been studied on the ground, using automatic weather station (AWS) data from the Greenland-Climate Network (GC-Net), and from analysis of satellite sensor data. Using Advanced Very High Frequency Radiometer (AVHRR) weekly surface temperature maps, warming of the surface of the Greenland Ice Sheet has been documented since 1981. We extended and refined this record using higher-resolution Moderate-Resolution Imaging Spectroradiometer (MODIS) data from March 2000 to the present. We developed a daily and monthly climate-data record (CDR) of the "clear-sky" surface temperature of the Greenland Ice Sheet using an ice-surface temperature (1ST) algorithm developed for use with MODIS data. Validation of this CDR is ongoing. MODIS Terra swath data are projected onto a polar stereographic grid at 6.25-km resolution to develop binary, gridded daily and mean-monthly 1ST maps. Each monthly map also has a color-coded image map that is available to download. Also included with the monthly maps is an accompanying map showing number of days in the month that were used to calculate the mean-monthly 1ST. This is important because no 1ST decision is made by the algorithm for cells that are considered cloudy by the internal cloud mask, so a sufficient number of days must be available to produce a mean 1ST for each grid cell. Validation of the CDR consists of several facets: 1) comparisons between ISTs and in-situ measurements; 2) comparisons between ISTs and AWS data; and 3) comparisons of ISTs with surface temperatures derived from other satellite instruments such as the Thermal Emission and Reflection Radiometer (ASTER) and Enhanced Thematic Mapper Plus (ETM+). Previous work shows that Terra MODIS ISTs are about 3 C lower than in-situ temperatures measured at Summit Camp, during the winter of 2008-09 under clear skies. In this work we begin to compare surface temperatures derived from AWS data with ISTs from the MODIS CDR. The Greenland Ice Sheet 1ST CDR will be useful for monitoring surface-temperature trends and can be used as input or for validation of climate models. The CDR can be extended into the future using MODIS Terra, Aqua and NPOESS Preparatory Project Visible Infrared Imager Radiometer Suite (VII RS) data. Other/Unknown Material Greenland Ice Sheet NASA Technical Reports Server (NTRS) Greenland Summit Camp ENVELOPE(-38.453,-38.453,72.579,72.579) |
institution |
Open Polar |
collection |
NASA Technical Reports Server (NTRS) |
op_collection_id |
ftnasantrs |
language |
unknown |
topic |
Meteorology and Climatology |
spellingShingle |
Meteorology and Climatology Hall, Dorothy K. DiGirolamo, Nicolo E. Comiso, Josefino C. Shuman, Christopher A. Koenig, Lora S. Box, Jason E. Validation of a Climate-Data Record of the "Clear-Kky" Surface Temperature of the Greenland Ice Sheet |
topic_facet |
Meteorology and Climatology |
description |
Surface temperatures on the Greenland Ice Sheet have been studied on the ground, using automatic weather station (AWS) data from the Greenland-Climate Network (GC-Net), and from analysis of satellite sensor data. Using Advanced Very High Frequency Radiometer (AVHRR) weekly surface temperature maps, warming of the surface of the Greenland Ice Sheet has been documented since 1981. We extended and refined this record using higher-resolution Moderate-Resolution Imaging Spectroradiometer (MODIS) data from March 2000 to the present. We developed a daily and monthly climate-data record (CDR) of the "clear-sky" surface temperature of the Greenland Ice Sheet using an ice-surface temperature (1ST) algorithm developed for use with MODIS data. Validation of this CDR is ongoing. MODIS Terra swath data are projected onto a polar stereographic grid at 6.25-km resolution to develop binary, gridded daily and mean-monthly 1ST maps. Each monthly map also has a color-coded image map that is available to download. Also included with the monthly maps is an accompanying map showing number of days in the month that were used to calculate the mean-monthly 1ST. This is important because no 1ST decision is made by the algorithm for cells that are considered cloudy by the internal cloud mask, so a sufficient number of days must be available to produce a mean 1ST for each grid cell. Validation of the CDR consists of several facets: 1) comparisons between ISTs and in-situ measurements; 2) comparisons between ISTs and AWS data; and 3) comparisons of ISTs with surface temperatures derived from other satellite instruments such as the Thermal Emission and Reflection Radiometer (ASTER) and Enhanced Thematic Mapper Plus (ETM+). Previous work shows that Terra MODIS ISTs are about 3 C lower than in-situ temperatures measured at Summit Camp, during the winter of 2008-09 under clear skies. In this work we begin to compare surface temperatures derived from AWS data with ISTs from the MODIS CDR. The Greenland Ice Sheet 1ST CDR will be useful for monitoring surface-temperature trends and can be used as input or for validation of climate models. The CDR can be extended into the future using MODIS Terra, Aqua and NPOESS Preparatory Project Visible Infrared Imager Radiometer Suite (VII RS) data. |
format |
Other/Unknown Material |
author |
Hall, Dorothy K. DiGirolamo, Nicolo E. Comiso, Josefino C. Shuman, Christopher A. Koenig, Lora S. Box, Jason E. |
author_facet |
Hall, Dorothy K. DiGirolamo, Nicolo E. Comiso, Josefino C. Shuman, Christopher A. Koenig, Lora S. Box, Jason E. |
author_sort |
Hall, Dorothy K. |
title |
Validation of a Climate-Data Record of the "Clear-Kky" Surface Temperature of the Greenland Ice Sheet |
title_short |
Validation of a Climate-Data Record of the "Clear-Kky" Surface Temperature of the Greenland Ice Sheet |
title_full |
Validation of a Climate-Data Record of the "Clear-Kky" Surface Temperature of the Greenland Ice Sheet |
title_fullStr |
Validation of a Climate-Data Record of the "Clear-Kky" Surface Temperature of the Greenland Ice Sheet |
title_full_unstemmed |
Validation of a Climate-Data Record of the "Clear-Kky" Surface Temperature of the Greenland Ice Sheet |
title_sort |
validation of a climate-data record of the "clear-kky" surface temperature of the greenland ice sheet |
publishDate |
2011 |
url |
http://hdl.handle.net/2060/20110013378 |
op_coverage |
Unclassified, Unlimited, Publicly available |
long_lat |
ENVELOPE(-38.453,-38.453,72.579,72.579) |
geographic |
Greenland Summit Camp |
geographic_facet |
Greenland Summit Camp |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_source |
CASI |
op_relation |
Document ID: 20110013378 http://hdl.handle.net/2060/20110013378 |
op_rights |
Copyright, Distribution as joint owner in the copyright |
_version_ |
1766015512058265600 |