A Long-Term Passive Microwave Snowoff Record for the Alaska Region 1988–2016
Snowoff (SO) date—defined as the last day of observed seasonal snow cover—is an important governor of ecologic and hydrologic processes across Alaska and Arctic-Boreal landscapes; however, our understanding and capacity for the monitoring of spatial and temporal variability in the SO date is still l...
Published in: | Remote Sensing |
---|---|
Main Authors: | , , , |
Format: | Text |
Language: | English |
Published: |
Multidisciplinary Digital Publishing Institute
2020
|
Subjects: | |
Online Access: | https://doi.org/10.3390/rs12010153 |
id |
ftmdpi:oai:mdpi.com:/2072-4292/12/1/153/ |
---|---|
record_format |
openpolar |
spelling |
ftmdpi:oai:mdpi.com:/2072-4292/12/1/153/ 2023-08-20T03:59:15+02:00 A Long-Term Passive Microwave Snowoff Record for the Alaska Region 1988–2016 Caleb G. Pan Peter B. Kirchner John S. Kimball Jinyang Du agris 2020-01-02 application/pdf https://doi.org/10.3390/rs12010153 EN eng Multidisciplinary Digital Publishing Institute https://dx.doi.org/10.3390/rs12010153 https://creativecommons.org/licenses/by/4.0/ Remote Sensing; Volume 12; Issue 1; Pages: 153 snow cover snowoff snow melt passive microwave Alaska Arctic Text 2020 ftmdpi https://doi.org/10.3390/rs12010153 2023-07-31T22:57:31Z Snowoff (SO) date—defined as the last day of observed seasonal snow cover—is an important governor of ecologic and hydrologic processes across Alaska and Arctic-Boreal landscapes; however, our understanding and capacity for the monitoring of spatial and temporal variability in the SO date is still lacking. In this study, we present a 6.25 km spatially gridded passive microwave (PMW) SO data record, complimenting current Alaskan SO records from Moderate Resolution Imaging Spectrometer (MODIS) and Landsat, but extending the SO record an additional 13 years. The PMW SO record was validated against in situ snow depth observations and showed favorable accuracy (0.66–0.92 mean correlations; 2–10 day mean absolute errors) for the major climate regions of Alaska. The PMW SO results were also within 10 days of finer spatial scale SO observational records, including Interactive Multisensor Snow and Ice Mapping System (IMS), MODIS, and Landsat, for a majority (75%) of Alaska. However, the PMW record showed a general SO delay at higher elevations and across the Alaska North Slope, and earlier SO in the Alaska interior and southwest regions relative to the other SO records. Overall, we assign an uncertainty +/−11 days to the PMW SO. The PMW SO record benefits from the near-daily temporal fidelity of underlying brightness temperature (Tb) observations and reveals a mean regional trend in earlier SO timing (−0.39 days yr−1), while significant (p < 0.1) SO trend areas encompassed 11% of the Alaska domain and ranged from −0.11 days yr−1 to −1.31 days yr−1 over the 29-year satellite record. The observed SO dates also showed anomalous early SO dates during markedly warm years. Our results clarify the pattern and rate of SO changes across Alaska, which are interactive with global warming and contributing to widespread permafrost degradation, changes in regional hydrology, ecosystems, and associated services. Our results also provide a robust means for SO monitoring from satellite PMW observations with similar precision as more ... Text Alaska North Slope Arctic Global warming Ice north slope permafrost Alaska MDPI Open Access Publishing Arctic Remote Sensing 12 1 153 |
institution |
Open Polar |
collection |
MDPI Open Access Publishing |
op_collection_id |
ftmdpi |
language |
English |
topic |
snow cover snowoff snow melt passive microwave Alaska Arctic |
spellingShingle |
snow cover snowoff snow melt passive microwave Alaska Arctic Caleb G. Pan Peter B. Kirchner John S. Kimball Jinyang Du A Long-Term Passive Microwave Snowoff Record for the Alaska Region 1988–2016 |
topic_facet |
snow cover snowoff snow melt passive microwave Alaska Arctic |
description |
Snowoff (SO) date—defined as the last day of observed seasonal snow cover—is an important governor of ecologic and hydrologic processes across Alaska and Arctic-Boreal landscapes; however, our understanding and capacity for the monitoring of spatial and temporal variability in the SO date is still lacking. In this study, we present a 6.25 km spatially gridded passive microwave (PMW) SO data record, complimenting current Alaskan SO records from Moderate Resolution Imaging Spectrometer (MODIS) and Landsat, but extending the SO record an additional 13 years. The PMW SO record was validated against in situ snow depth observations and showed favorable accuracy (0.66–0.92 mean correlations; 2–10 day mean absolute errors) for the major climate regions of Alaska. The PMW SO results were also within 10 days of finer spatial scale SO observational records, including Interactive Multisensor Snow and Ice Mapping System (IMS), MODIS, and Landsat, for a majority (75%) of Alaska. However, the PMW record showed a general SO delay at higher elevations and across the Alaska North Slope, and earlier SO in the Alaska interior and southwest regions relative to the other SO records. Overall, we assign an uncertainty +/−11 days to the PMW SO. The PMW SO record benefits from the near-daily temporal fidelity of underlying brightness temperature (Tb) observations and reveals a mean regional trend in earlier SO timing (−0.39 days yr−1), while significant (p < 0.1) SO trend areas encompassed 11% of the Alaska domain and ranged from −0.11 days yr−1 to −1.31 days yr−1 over the 29-year satellite record. The observed SO dates also showed anomalous early SO dates during markedly warm years. Our results clarify the pattern and rate of SO changes across Alaska, which are interactive with global warming and contributing to widespread permafrost degradation, changes in regional hydrology, ecosystems, and associated services. Our results also provide a robust means for SO monitoring from satellite PMW observations with similar precision as more ... |
format |
Text |
author |
Caleb G. Pan Peter B. Kirchner John S. Kimball Jinyang Du |
author_facet |
Caleb G. Pan Peter B. Kirchner John S. Kimball Jinyang Du |
author_sort |
Caleb G. Pan |
title |
A Long-Term Passive Microwave Snowoff Record for the Alaska Region 1988–2016 |
title_short |
A Long-Term Passive Microwave Snowoff Record for the Alaska Region 1988–2016 |
title_full |
A Long-Term Passive Microwave Snowoff Record for the Alaska Region 1988–2016 |
title_fullStr |
A Long-Term Passive Microwave Snowoff Record for the Alaska Region 1988–2016 |
title_full_unstemmed |
A Long-Term Passive Microwave Snowoff Record for the Alaska Region 1988–2016 |
title_sort |
long-term passive microwave snowoff record for the alaska region 1988–2016 |
publisher |
Multidisciplinary Digital Publishing Institute |
publishDate |
2020 |
url |
https://doi.org/10.3390/rs12010153 |
op_coverage |
agris |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Alaska North Slope Arctic Global warming Ice north slope permafrost Alaska |
genre_facet |
Alaska North Slope Arctic Global warming Ice north slope permafrost Alaska |
op_source |
Remote Sensing; Volume 12; Issue 1; Pages: 153 |
op_relation |
https://dx.doi.org/10.3390/rs12010153 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.3390/rs12010153 |
container_title |
Remote Sensing |
container_volume |
12 |
container_issue |
1 |
container_start_page |
153 |
_version_ |
1774724698135855104 |