Short-term geomorphic dynamics of the Yukon and Herschel Island coasts based on LIDAR DEMs from 2012 and 2013
Arctic permafrost coasts, especially when they are unconsolidated and ground ice rich, are extremely vulnerable to climate change. Rising temperatures of air and seawater, lengthening of the open-water season and increase in storm events are likely to prompt higher rates of coastal erosion and conse...
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ftawi:oai:epic.awi.de:35812 2023-05-15T15:05:52+02:00 Short-term geomorphic dynamics of the Yukon and Herschel Island coasts based on LIDAR DEMs from 2012 and 2013 Obu, Jaroslav Lantuit, Hugues Fritz, Michael Grosse, Guido Sachs, Torsten Helm, Veit 2014-06-20 application/pdf https://epic.awi.de/id/eprint/35812/ https://epic.awi.de/id/eprint/35812/1/EUCOP_Obu_poster.pdf https://hdl.handle.net/10013/epic.43741 https://hdl.handle.net/10013/epic.43741.d001 unknown https://epic.awi.de/id/eprint/35812/1/EUCOP_Obu_poster.pdf https://hdl.handle.net/10013/epic.43741.d001 Obu, J. , Lantuit, H. orcid:0000-0003-1497-6760 , Fritz, M. orcid:0000-0003-4591-7325 , Grosse, G. orcid:0000-0001-5895-2141 , Sachs, T. and Helm, V. orcid:0000-0001-7788-9328 (2014) Short-term geomorphic dynamics of the Yukon and Herschel Island coasts based on LIDAR DEMs from 2012 and 2013 , EUCOP4 European Conference on Permafrost, Evora, Portugal, 19 June 2014 - 21 June 2014 . hdl:10013/epic.43741 EPIC3EUCOP4 European Conference on Permafrost, Evora, Portugal, 2014-06-19-2014-06-21 Conference notRev 2014 ftawi 2021-12-24T15:39:38Z Arctic permafrost coasts, especially when they are unconsolidated and ground ice rich, are extremely vulnerable to climate change. Rising temperatures of air and seawater, lengthening of the open-water season and increase in storm events are likely to prompt higher rates of coastal erosion and consequently increase the rate of land loss and material transport to the near-shore zone. Many studies have addressed this issue by compiling rates of shoreline erosion over the past fifty to sixty years to find trends, yet few investigations have attempted to look at it in three dimensions and at annual time scales, although erosion of Arctic coasts is known to be very complex and nonlinear. This study focuses on high resolution short-term (one year) erosion rates and geomorphic change. It is based on DEMs that were obtained from LIDAR surveys of the Yukon Coast and Herschel Island during the AIRMETH campaigns in 2012 and 2013. The DEMs were processed to obtain a horizontal resolution of 1 meter and serve as an elevation source from which the comparison was made. The elevations from the 2012 DEM were then deducted from elevations in 2013 to obtain erosion and accumulation values for each pixel. Preliminary results show that coastal retreat encompasses a range of processes acting at different temporal and spatial scales. They can be divided into denudation and abrasion processes. Denudation is the various types of mass wasting, such as translational slides, active layer detachments or retrogressive thaw slumps. The material delivered from these abrupt events is made available for abrasion, which is transferring the material to the shoreface at longer time scales. The accumulated material temporarily protects cliffs from incident wave energy and abrasion is reactivated when the material is removed. The erosion from gullies and thermo-erosional valleys is another form of material delivery to coast. Shoreline retreats from 2 to 5 meters were recorded on the most exposed parts of the coast, while vertical changes of cliffs account locally for more than 10 meters and extend up to 20 meters laterally. Locations where these high numbers are observed are often characterised by the adjacent accumulation of material on the beach. This study shows that the pathways for the transfer of material from the coast to the sea are very diverse and are often limited by the ability of abrasion to remove material delivered by the mass wasting of coastal bluffs. Conference Object Arctic Climate change Herschel Herschel Island Ice permafrost Yukon Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Arctic Herschel Island ENVELOPE(-139.089,-139.089,69.583,69.583) Yukon |
institution |
Open Polar |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
Arctic permafrost coasts, especially when they are unconsolidated and ground ice rich, are extremely vulnerable to climate change. Rising temperatures of air and seawater, lengthening of the open-water season and increase in storm events are likely to prompt higher rates of coastal erosion and consequently increase the rate of land loss and material transport to the near-shore zone. Many studies have addressed this issue by compiling rates of shoreline erosion over the past fifty to sixty years to find trends, yet few investigations have attempted to look at it in three dimensions and at annual time scales, although erosion of Arctic coasts is known to be very complex and nonlinear. This study focuses on high resolution short-term (one year) erosion rates and geomorphic change. It is based on DEMs that were obtained from LIDAR surveys of the Yukon Coast and Herschel Island during the AIRMETH campaigns in 2012 and 2013. The DEMs were processed to obtain a horizontal resolution of 1 meter and serve as an elevation source from which the comparison was made. The elevations from the 2012 DEM were then deducted from elevations in 2013 to obtain erosion and accumulation values for each pixel. Preliminary results show that coastal retreat encompasses a range of processes acting at different temporal and spatial scales. They can be divided into denudation and abrasion processes. Denudation is the various types of mass wasting, such as translational slides, active layer detachments or retrogressive thaw slumps. The material delivered from these abrupt events is made available for abrasion, which is transferring the material to the shoreface at longer time scales. The accumulated material temporarily protects cliffs from incident wave energy and abrasion is reactivated when the material is removed. The erosion from gullies and thermo-erosional valleys is another form of material delivery to coast. Shoreline retreats from 2 to 5 meters were recorded on the most exposed parts of the coast, while vertical changes of cliffs account locally for more than 10 meters and extend up to 20 meters laterally. Locations where these high numbers are observed are often characterised by the adjacent accumulation of material on the beach. This study shows that the pathways for the transfer of material from the coast to the sea are very diverse and are often limited by the ability of abrasion to remove material delivered by the mass wasting of coastal bluffs. |
format |
Conference Object |
author |
Obu, Jaroslav Lantuit, Hugues Fritz, Michael Grosse, Guido Sachs, Torsten Helm, Veit |
spellingShingle |
Obu, Jaroslav Lantuit, Hugues Fritz, Michael Grosse, Guido Sachs, Torsten Helm, Veit Short-term geomorphic dynamics of the Yukon and Herschel Island coasts based on LIDAR DEMs from 2012 and 2013 |
author_facet |
Obu, Jaroslav Lantuit, Hugues Fritz, Michael Grosse, Guido Sachs, Torsten Helm, Veit |
author_sort |
Obu, Jaroslav |
title |
Short-term geomorphic dynamics of the Yukon and Herschel Island coasts based on LIDAR DEMs from 2012 and 2013 |
title_short |
Short-term geomorphic dynamics of the Yukon and Herschel Island coasts based on LIDAR DEMs from 2012 and 2013 |
title_full |
Short-term geomorphic dynamics of the Yukon and Herschel Island coasts based on LIDAR DEMs from 2012 and 2013 |
title_fullStr |
Short-term geomorphic dynamics of the Yukon and Herschel Island coasts based on LIDAR DEMs from 2012 and 2013 |
title_full_unstemmed |
Short-term geomorphic dynamics of the Yukon and Herschel Island coasts based on LIDAR DEMs from 2012 and 2013 |
title_sort |
short-term geomorphic dynamics of the yukon and herschel island coasts based on lidar dems from 2012 and 2013 |
publishDate |
2014 |
url |
https://epic.awi.de/id/eprint/35812/ https://epic.awi.de/id/eprint/35812/1/EUCOP_Obu_poster.pdf https://hdl.handle.net/10013/epic.43741 https://hdl.handle.net/10013/epic.43741.d001 |
long_lat |
ENVELOPE(-139.089,-139.089,69.583,69.583) |
geographic |
Arctic Herschel Island Yukon |
geographic_facet |
Arctic Herschel Island Yukon |
genre |
Arctic Climate change Herschel Herschel Island Ice permafrost Yukon |
genre_facet |
Arctic Climate change Herschel Herschel Island Ice permafrost Yukon |
op_source |
EPIC3EUCOP4 European Conference on Permafrost, Evora, Portugal, 2014-06-19-2014-06-21 |
op_relation |
https://epic.awi.de/id/eprint/35812/1/EUCOP_Obu_poster.pdf https://hdl.handle.net/10013/epic.43741.d001 Obu, J. , Lantuit, H. orcid:0000-0003-1497-6760 , Fritz, M. orcid:0000-0003-4591-7325 , Grosse, G. orcid:0000-0001-5895-2141 , Sachs, T. and Helm, V. orcid:0000-0001-7788-9328 (2014) Short-term geomorphic dynamics of the Yukon and Herschel Island coasts based on LIDAR DEMs from 2012 and 2013 , EUCOP4 European Conference on Permafrost, Evora, Portugal, 19 June 2014 - 21 June 2014 . hdl:10013/epic.43741 |
_version_ |
1766337539905421312 |