Active Layer Subsidence: An Indicator of Change
The active layer is the most dynamic and sensitive subsurface component of the permafrost environment. The thickness of the active layer is expected to increase in a warmer climate. It has been widely documented that both the annual air temperature and permafrost temperatures are increasing. However...
Main Authors: | , , , |
---|---|
Format: | Conference Object |
Language: | unknown |
Published: |
2010
|
Subjects: | |
Online Access: | https://epic.awi.de/id/eprint/22774/ https://hdl.handle.net/10013/epic.35471 |
id |
ftawi:oai:epic.awi.de:22774 |
---|---|
record_format |
openpolar |
spelling |
ftawi:oai:epic.awi.de:22774 2024-09-15T17:34:51+00:00 Active Layer Subsidence: An Indicator of Change Kane, D. L. Overduin, Pier Paul Nelson, F. E. Shiklomanov, N. I. 2010 https://epic.awi.de/id/eprint/22774/ https://hdl.handle.net/10013/epic.35471 unknown Kane, D. L. , Overduin, P. P. orcid:0000-0001-9849-4712 , Nelson, F. E. and Shiklomanov, N. I. (2010) Active Layer Subsidence: An Indicator of Change , Third European Conference on Permafrost, Longyearbyen, Svalbard, Norway, June 13-17 . hdl:10013/epic.35471 EPIC3Third European Conference on Permafrost, Longyearbyen, Svalbard, Norway, June 13-17, 2010 p. Conference notRev 2010 ftawi 2024-06-24T04:02:26Z The active layer is the most dynamic and sensitive subsurface component of the permafrost environment. The thickness of the active layer is expected to increase in a warmer climate. It has been widely documented that both the annual air temperature and permafrost temperatures are increasing. However, in many cases it does not appear to be true that the thickness of the active layer has increased substantially over the past decade. Part of this situation can be explained by short observational records and natural variability. Recorded air temperature observations exist for over 100 years, while active-layer thickness observations have only been recorded continuously over the past 15-20 years. After a few years of observations it was realized that another process was possibly masking the process of deeper active layer thaw. A new protocol strategy for measuring active-layer thickness was initiated by several research groups in northern Alaska. It quickly became clear that there was subsidence (thaw settlement) in the active layer and that this occurs in response to thawing of ice-rich soils at the base of the active layer or uppermost permafrost. The relevant questions of interest are: what is the typical annual amount of subsidence that can be expected, how long can this process of subsidence be sustained and what is the significance of this process? Increased active-layer thickness has hydrologic implications, as it increases subsurface storage and will both prolong drainage and freezing in the fall. If subsidence occurs during the thawing process, excess water is released for runoff and evapotranspiration. Long-term effects could involve changes in soil moisture, vegetation, and geomorphic processes. In low-lying coastal areas, the rate of subsidence could hypothetically eclipse sea level rise; and these areas could become inundated sooner than expected and become more susceptible to storm surges. All of this depends upon the distribution, horizontally and vertically, of the ice-rich layer at the base of the ... Conference Object Active layer thickness Ice permafrost Alaska Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
institution |
Open Polar |
collection |
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
The active layer is the most dynamic and sensitive subsurface component of the permafrost environment. The thickness of the active layer is expected to increase in a warmer climate. It has been widely documented that both the annual air temperature and permafrost temperatures are increasing. However, in many cases it does not appear to be true that the thickness of the active layer has increased substantially over the past decade. Part of this situation can be explained by short observational records and natural variability. Recorded air temperature observations exist for over 100 years, while active-layer thickness observations have only been recorded continuously over the past 15-20 years. After a few years of observations it was realized that another process was possibly masking the process of deeper active layer thaw. A new protocol strategy for measuring active-layer thickness was initiated by several research groups in northern Alaska. It quickly became clear that there was subsidence (thaw settlement) in the active layer and that this occurs in response to thawing of ice-rich soils at the base of the active layer or uppermost permafrost. The relevant questions of interest are: what is the typical annual amount of subsidence that can be expected, how long can this process of subsidence be sustained and what is the significance of this process? Increased active-layer thickness has hydrologic implications, as it increases subsurface storage and will both prolong drainage and freezing in the fall. If subsidence occurs during the thawing process, excess water is released for runoff and evapotranspiration. Long-term effects could involve changes in soil moisture, vegetation, and geomorphic processes. In low-lying coastal areas, the rate of subsidence could hypothetically eclipse sea level rise; and these areas could become inundated sooner than expected and become more susceptible to storm surges. All of this depends upon the distribution, horizontally and vertically, of the ice-rich layer at the base of the ... |
format |
Conference Object |
author |
Kane, D. L. Overduin, Pier Paul Nelson, F. E. Shiklomanov, N. I. |
spellingShingle |
Kane, D. L. Overduin, Pier Paul Nelson, F. E. Shiklomanov, N. I. Active Layer Subsidence: An Indicator of Change |
author_facet |
Kane, D. L. Overduin, Pier Paul Nelson, F. E. Shiklomanov, N. I. |
author_sort |
Kane, D. L. |
title |
Active Layer Subsidence: An Indicator of Change |
title_short |
Active Layer Subsidence: An Indicator of Change |
title_full |
Active Layer Subsidence: An Indicator of Change |
title_fullStr |
Active Layer Subsidence: An Indicator of Change |
title_full_unstemmed |
Active Layer Subsidence: An Indicator of Change |
title_sort |
active layer subsidence: an indicator of change |
publishDate |
2010 |
url |
https://epic.awi.de/id/eprint/22774/ https://hdl.handle.net/10013/epic.35471 |
genre |
Active layer thickness Ice permafrost Alaska |
genre_facet |
Active layer thickness Ice permafrost Alaska |
op_source |
EPIC3Third European Conference on Permafrost, Longyearbyen, Svalbard, Norway, June 13-17, 2010 p. |
op_relation |
Kane, D. L. , Overduin, P. P. orcid:0000-0001-9849-4712 , Nelson, F. E. and Shiklomanov, N. I. (2010) Active Layer Subsidence: An Indicator of Change , Third European Conference on Permafrost, Longyearbyen, Svalbard, Norway, June 13-17 . hdl:10013/epic.35471 |
_version_ |
1810430463140954112 |