Estimating Temperature Fields from MODIS Land Surface Temperature and Air Temperature Observations in a Sub-Arctic Alpine Environment
Spatially continuous satellite infrared temperature measurements are essential for understanding the consequences and drivers of change, at local and regional scales, especially in northern and alpine environments dominated by a complex cryosphere where in situ observations are scarce. We describe t...
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ftunivnebraskali:oai:digitalcommons.unl.edu:natrespapers-1879 2023-11-12T04:14:01+01:00 Estimating Temperature Fields from MODIS Land Surface Temperature and Air Temperature Observations in a Sub-Arctic Alpine Environment Williamson, Scott N. Hik, David S. Gamon, John A. Kavanaugh, Jeffrey L. Flowers, Gwenn E. 2014-01-24T08:00:00Z application/pdf https://digitalcommons.unl.edu/natrespapers/869 https://digitalcommons.unl.edu/context/natrespapers/article/1879/viewcontent/WilliamsonRemoteSensing2014EstimatingTemperature.pdf unknown DigitalCommons@University of Nebraska - Lincoln https://digitalcommons.unl.edu/natrespapers/869 https://digitalcommons.unl.edu/context/natrespapers/article/1879/viewcontent/WilliamsonRemoteSensing2014EstimatingTemperature.pdf Papers in Natural Resources mean daily surface temperature land surface temperature air temperature MODIS meteorological station tundra Yukon Canada Environmental Sciences Natural Resources and Conservation Natural Resources Management and Policy Other Environmental Sciences text 2014 ftunivnebraskali 2023-10-30T11:46:14Z Spatially continuous satellite infrared temperature measurements are essential for understanding the consequences and drivers of change, at local and regional scales, especially in northern and alpine environments dominated by a complex cryosphere where in situ observations are scarce. We describe two methods for producing daily temperature fields using MODIS ―clear-sky‖ day-time Land Surface Temperatures (LST). The Interpolated Curve Mean Daily Surface Temperature (ICM) method, interpolates single daytime Terra LST values to daily means using the coincident diurnal air temperature curves. The second method calculates daily mean LST from daily maximum and minimum LST (MMM) values from MODIS Aqua and Terra. These ICM and MMM models were compared to daily mean air temperatures recorded between April and October at seven locations in southwest Yukon, Canada, covering characteristic alpine land cover types (tundra, barren, glacier) at elevations between 1,408 m and 2,319 m. Both methods for producing mean daily surface temperatures have advantages and disadvantages. ICM signals are strongly correlated with air temperature (R2 = 0.72 to 0.86), but have relatively large variability (RMSE = 4.09 to 4.90 K), while MMM values had a stronger correlation to air temperature (R2 = 0.90) and smaller variability (RMSE = 2.67 K). Finally, when comparing 8-day LST averages, aggregated from the MMM method, to air temperature, we found a high correlation (R2 = 0.84) with less variability (RMSE = 1.54 K). Where the trend was less steep and the y-intercept increased by 1.6 °C compared to the daily correlations. This effect is likely a consequence of LST temperature averages being differentially affected by cloud cover over warm and cold surfaces. We conclude that satellite infrared skin temperature (e.g., MODIS LST), which is often aggregated into multi-day composites to mitigate data reductions caused by cloud cover, changes in its relationship to air temperature depending on the period of aggregation. Text Arctic glacier* Tundra Yukon University of Nebraska-Lincoln: DigitalCommons@UNL Arctic Yukon Canada The ''Y'' ENVELOPE(-112.453,-112.453,57.591,57.591) |
institution |
Open Polar |
collection |
University of Nebraska-Lincoln: DigitalCommons@UNL |
op_collection_id |
ftunivnebraskali |
language |
unknown |
topic |
mean daily surface temperature land surface temperature air temperature MODIS meteorological station tundra Yukon Canada Environmental Sciences Natural Resources and Conservation Natural Resources Management and Policy Other Environmental Sciences |
spellingShingle |
mean daily surface temperature land surface temperature air temperature MODIS meteorological station tundra Yukon Canada Environmental Sciences Natural Resources and Conservation Natural Resources Management and Policy Other Environmental Sciences Williamson, Scott N. Hik, David S. Gamon, John A. Kavanaugh, Jeffrey L. Flowers, Gwenn E. Estimating Temperature Fields from MODIS Land Surface Temperature and Air Temperature Observations in a Sub-Arctic Alpine Environment |
topic_facet |
mean daily surface temperature land surface temperature air temperature MODIS meteorological station tundra Yukon Canada Environmental Sciences Natural Resources and Conservation Natural Resources Management and Policy Other Environmental Sciences |
description |
Spatially continuous satellite infrared temperature measurements are essential for understanding the consequences and drivers of change, at local and regional scales, especially in northern and alpine environments dominated by a complex cryosphere where in situ observations are scarce. We describe two methods for producing daily temperature fields using MODIS ―clear-sky‖ day-time Land Surface Temperatures (LST). The Interpolated Curve Mean Daily Surface Temperature (ICM) method, interpolates single daytime Terra LST values to daily means using the coincident diurnal air temperature curves. The second method calculates daily mean LST from daily maximum and minimum LST (MMM) values from MODIS Aqua and Terra. These ICM and MMM models were compared to daily mean air temperatures recorded between April and October at seven locations in southwest Yukon, Canada, covering characteristic alpine land cover types (tundra, barren, glacier) at elevations between 1,408 m and 2,319 m. Both methods for producing mean daily surface temperatures have advantages and disadvantages. ICM signals are strongly correlated with air temperature (R2 = 0.72 to 0.86), but have relatively large variability (RMSE = 4.09 to 4.90 K), while MMM values had a stronger correlation to air temperature (R2 = 0.90) and smaller variability (RMSE = 2.67 K). Finally, when comparing 8-day LST averages, aggregated from the MMM method, to air temperature, we found a high correlation (R2 = 0.84) with less variability (RMSE = 1.54 K). Where the trend was less steep and the y-intercept increased by 1.6 °C compared to the daily correlations. This effect is likely a consequence of LST temperature averages being differentially affected by cloud cover over warm and cold surfaces. We conclude that satellite infrared skin temperature (e.g., MODIS LST), which is often aggregated into multi-day composites to mitigate data reductions caused by cloud cover, changes in its relationship to air temperature depending on the period of aggregation. |
format |
Text |
author |
Williamson, Scott N. Hik, David S. Gamon, John A. Kavanaugh, Jeffrey L. Flowers, Gwenn E. |
author_facet |
Williamson, Scott N. Hik, David S. Gamon, John A. Kavanaugh, Jeffrey L. Flowers, Gwenn E. |
author_sort |
Williamson, Scott N. |
title |
Estimating Temperature Fields from MODIS Land Surface Temperature and Air Temperature Observations in a Sub-Arctic Alpine Environment |
title_short |
Estimating Temperature Fields from MODIS Land Surface Temperature and Air Temperature Observations in a Sub-Arctic Alpine Environment |
title_full |
Estimating Temperature Fields from MODIS Land Surface Temperature and Air Temperature Observations in a Sub-Arctic Alpine Environment |
title_fullStr |
Estimating Temperature Fields from MODIS Land Surface Temperature and Air Temperature Observations in a Sub-Arctic Alpine Environment |
title_full_unstemmed |
Estimating Temperature Fields from MODIS Land Surface Temperature and Air Temperature Observations in a Sub-Arctic Alpine Environment |
title_sort |
estimating temperature fields from modis land surface temperature and air temperature observations in a sub-arctic alpine environment |
publisher |
DigitalCommons@University of Nebraska - Lincoln |
publishDate |
2014 |
url |
https://digitalcommons.unl.edu/natrespapers/869 https://digitalcommons.unl.edu/context/natrespapers/article/1879/viewcontent/WilliamsonRemoteSensing2014EstimatingTemperature.pdf |
long_lat |
ENVELOPE(-112.453,-112.453,57.591,57.591) |
geographic |
Arctic Yukon Canada The ''Y'' |
geographic_facet |
Arctic Yukon Canada The ''Y'' |
genre |
Arctic glacier* Tundra Yukon |
genre_facet |
Arctic glacier* Tundra Yukon |
op_source |
Papers in Natural Resources |
op_relation |
https://digitalcommons.unl.edu/natrespapers/869 https://digitalcommons.unl.edu/context/natrespapers/article/1879/viewcontent/WilliamsonRemoteSensing2014EstimatingTemperature.pdf |
_version_ |
1782331764651327488 |