Spatial Sampling Design in the Circumpolar Active Layer Monitoring Programme
Prior to development of the Circumpolar Active Layer Monitoring (CALM) programme, little attention was paid to formal spatial sampling designs for measuring active‐layer thickness (ALT). This omission made the accuracy of many data‐sets questionable, in part because spatial periodicities caused by l...
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Online Access: | https://doi.org/10.1002/ppp.1904 |
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ftrepec:oai:RePEc:wly:perpro:v:28:y:2017:i:1:p:42-51 2023-05-15T13:02:37+02:00 Spatial Sampling Design in the Circumpolar Active Layer Monitoring Programme John D. Fagan Frederick E. Nelson https://doi.org/10.1002/ppp.1904 unknown https://doi.org/10.1002/ppp.1904 article ftrepec https://doi.org/10.1002/ppp.1904 2020-12-04T13:31:25Z Prior to development of the Circumpolar Active Layer Monitoring (CALM) programme, little attention was paid to formal spatial sampling designs for measuring active‐layer thickness (ALT). This omission made the accuracy of many data‐sets questionable, in part because spatial periodicities caused by landscape features such as ice‐wedge polygons and thaw lakes can significantly influence the depth of thaw. Early in the development of CALM's protocols, ALT was sampled in the continuous permafrost zone in northern Alaska and simulated by computer, to determine how ALT could be measured accurately. The simulated and field data‐sets were analysed by comparing the means, variances and frequency distributions obtained using four spatial sampling designs (random, systematic, systematic random and systematic stratified unaligned). By a small margin, systematic stratified unaligned sampling provided the most accurate results. Systematic designs can, however, provide adequate estimates of the statistical moments of ALT with significant savings in cost, time and ease of implementation. Based on these results, the CALM programme recommended use of 10 x 10, 100 x 100 or 1000 x 1000 m grids, with sampling intervals of 1, 10 and 100 m, respectively. Most probed CALM sites now employ this strategy, except in terrain with unusual landscape elements or other special constraints. Copyright © 2016 John Wiley & Sons, Ltd. Article in Journal/Newspaper Active layer monitoring Active layer thickness Ice permafrost wedge* Alaska RePEc (Research Papers in Economics) Permafrost and Periglacial Processes 28 1 42 51 |
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Open Polar |
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RePEc (Research Papers in Economics) |
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Prior to development of the Circumpolar Active Layer Monitoring (CALM) programme, little attention was paid to formal spatial sampling designs for measuring active‐layer thickness (ALT). This omission made the accuracy of many data‐sets questionable, in part because spatial periodicities caused by landscape features such as ice‐wedge polygons and thaw lakes can significantly influence the depth of thaw. Early in the development of CALM's protocols, ALT was sampled in the continuous permafrost zone in northern Alaska and simulated by computer, to determine how ALT could be measured accurately. The simulated and field data‐sets were analysed by comparing the means, variances and frequency distributions obtained using four spatial sampling designs (random, systematic, systematic random and systematic stratified unaligned). By a small margin, systematic stratified unaligned sampling provided the most accurate results. Systematic designs can, however, provide adequate estimates of the statistical moments of ALT with significant savings in cost, time and ease of implementation. Based on these results, the CALM programme recommended use of 10 x 10, 100 x 100 or 1000 x 1000 m grids, with sampling intervals of 1, 10 and 100 m, respectively. Most probed CALM sites now employ this strategy, except in terrain with unusual landscape elements or other special constraints. Copyright © 2016 John Wiley & Sons, Ltd. |
format |
Article in Journal/Newspaper |
author |
John D. Fagan Frederick E. Nelson |
spellingShingle |
John D. Fagan Frederick E. Nelson Spatial Sampling Design in the Circumpolar Active Layer Monitoring Programme |
author_facet |
John D. Fagan Frederick E. Nelson |
author_sort |
John D. Fagan |
title |
Spatial Sampling Design in the Circumpolar Active Layer Monitoring Programme |
title_short |
Spatial Sampling Design in the Circumpolar Active Layer Monitoring Programme |
title_full |
Spatial Sampling Design in the Circumpolar Active Layer Monitoring Programme |
title_fullStr |
Spatial Sampling Design in the Circumpolar Active Layer Monitoring Programme |
title_full_unstemmed |
Spatial Sampling Design in the Circumpolar Active Layer Monitoring Programme |
title_sort |
spatial sampling design in the circumpolar active layer monitoring programme |
url |
https://doi.org/10.1002/ppp.1904 |
genre |
Active layer monitoring Active layer thickness Ice permafrost wedge* Alaska |
genre_facet |
Active layer monitoring Active layer thickness Ice permafrost wedge* Alaska |
op_relation |
https://doi.org/10.1002/ppp.1904 |
op_doi |
https://doi.org/10.1002/ppp.1904 |
container_title |
Permafrost and Periglacial Processes |
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28 |
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1 |
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42 |
op_container_end_page |
51 |
_version_ |
1766314724201332736 |