A Concept To Assess The Performance Of A Permafrost Model Run Fully Coupled With A Climate Model
Dissertation (Ph.D.) University of Alaska Fairbanks, 2009 Soil-temperatures simulated by the fully coupled Community Climate System Model LCM version 3.0 (CCSM3) are evaluated using three gridded Russian soil-temperature climatologies (1951-1980, 1961-1990, and 1971-2000) to assess the performance o...
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ftunivalaska:oai:scholarworks.alaska.edu:11122/9015 2023-05-15T17:57:38+02:00 A Concept To Assess The Performance Of A Permafrost Model Run Fully Coupled With A Climate Model Paimazumder, Debasish 2009 http://hdl.handle.net/11122/9015 unknown http://hdl.handle.net/11122/9015 Department of Atmospheric Sciences Atmospheric sciences Dissertation phd 2009 ftunivalaska 2023-02-23T21:37:11Z Dissertation (Ph.D.) University of Alaska Fairbanks, 2009 Soil-temperatures simulated by the fully coupled Community Climate System Model LCM version 3.0 (CCSM3) are evaluated using three gridded Russian soil-temperature climatologies (1951-1980, 1961-1990, and 1971-2000) to assess the performance of permafrost and/or soil simulations. CCSM3 captures the annual phase of the soil-temperature cycle well, but not the amplitude. It provides slightly too high (low) soil-temperatures in winter (summer) with a better performance in summer than winter. In winter, soil-temperature biases reach up to 6 K. Simulated near-surface air temperatures agree well with the near-surface air temperatures from reanalysis data. Discrepancies in CCSM3-simulated near-surface air temperatures significantly correlate with discrepancies in CCSM3-simulated soil-temperatures, i.e. contribute to discrepancy in soil-temperature simulation. Evaluation of cloud-fraction by means of the International Satellite Cloud Climatology project data reveals that errors in simulated cloud fraction explain some of the soil-temperature discrepancies in summer. Evaluation by means of the Global Precipitation Climatology Centre data identifies inaccurately-simulated precipitation as a contributor to underestimating summer soil-temperatures. Comparison to snow-depth observations shows that overestimating snow-depth leads to winter soil-temperature overestimation. Sensitivity studies reveal that uncertainty in mineral-soil composition notably contributes to discrepancies between CCSM3-simulated and observed soil-temperature climatology while differences between the assumed vegetation in CCSM3 and the actual vegetation in nature marginally contribute to the discrepancies in soil-temperature. Out of the 6 K bias in CCSM3 soil-temperature simulation, about 2.5 K of the bias may result from the incorrect simulation of the observed forcing and about 2 K of the bias may be explained by uncertainties due network density in winter. This means that about 1.5 K ... Doctoral or Postdoctoral Thesis permafrost Alaska University of Alaska: ScholarWorks@UA Fairbanks |
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University of Alaska: ScholarWorks@UA |
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Atmospheric sciences |
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Atmospheric sciences Paimazumder, Debasish A Concept To Assess The Performance Of A Permafrost Model Run Fully Coupled With A Climate Model |
topic_facet |
Atmospheric sciences |
description |
Dissertation (Ph.D.) University of Alaska Fairbanks, 2009 Soil-temperatures simulated by the fully coupled Community Climate System Model LCM version 3.0 (CCSM3) are evaluated using three gridded Russian soil-temperature climatologies (1951-1980, 1961-1990, and 1971-2000) to assess the performance of permafrost and/or soil simulations. CCSM3 captures the annual phase of the soil-temperature cycle well, but not the amplitude. It provides slightly too high (low) soil-temperatures in winter (summer) with a better performance in summer than winter. In winter, soil-temperature biases reach up to 6 K. Simulated near-surface air temperatures agree well with the near-surface air temperatures from reanalysis data. Discrepancies in CCSM3-simulated near-surface air temperatures significantly correlate with discrepancies in CCSM3-simulated soil-temperatures, i.e. contribute to discrepancy in soil-temperature simulation. Evaluation of cloud-fraction by means of the International Satellite Cloud Climatology project data reveals that errors in simulated cloud fraction explain some of the soil-temperature discrepancies in summer. Evaluation by means of the Global Precipitation Climatology Centre data identifies inaccurately-simulated precipitation as a contributor to underestimating summer soil-temperatures. Comparison to snow-depth observations shows that overestimating snow-depth leads to winter soil-temperature overestimation. Sensitivity studies reveal that uncertainty in mineral-soil composition notably contributes to discrepancies between CCSM3-simulated and observed soil-temperature climatology while differences between the assumed vegetation in CCSM3 and the actual vegetation in nature marginally contribute to the discrepancies in soil-temperature. Out of the 6 K bias in CCSM3 soil-temperature simulation, about 2.5 K of the bias may result from the incorrect simulation of the observed forcing and about 2 K of the bias may be explained by uncertainties due network density in winter. This means that about 1.5 K ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Paimazumder, Debasish |
author_facet |
Paimazumder, Debasish |
author_sort |
Paimazumder, Debasish |
title |
A Concept To Assess The Performance Of A Permafrost Model Run Fully Coupled With A Climate Model |
title_short |
A Concept To Assess The Performance Of A Permafrost Model Run Fully Coupled With A Climate Model |
title_full |
A Concept To Assess The Performance Of A Permafrost Model Run Fully Coupled With A Climate Model |
title_fullStr |
A Concept To Assess The Performance Of A Permafrost Model Run Fully Coupled With A Climate Model |
title_full_unstemmed |
A Concept To Assess The Performance Of A Permafrost Model Run Fully Coupled With A Climate Model |
title_sort |
concept to assess the performance of a permafrost model run fully coupled with a climate model |
publishDate |
2009 |
url |
http://hdl.handle.net/11122/9015 |
geographic |
Fairbanks |
geographic_facet |
Fairbanks |
genre |
permafrost Alaska |
genre_facet |
permafrost Alaska |
op_relation |
http://hdl.handle.net/11122/9015 Department of Atmospheric Sciences |
_version_ |
1766166112265830400 |