Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska
Landscape-scale impacts of climate change in the Arctic include increases in growing season length, shrubby vegetation, winter river discharge, snowfall, summer and winter water temperatures, and decreases in river and lake ice thickness. Combined, these changes may have created conditions that are...
Main Authors: | , , , , , |
---|---|
Format: | Conference Object |
Language: | unknown |
Published: |
2017
|
Subjects: | |
Online Access: | https://epic.awi.de/id/eprint/48574/ https://hdl.handle.net/10013/epic.ac03a4ee-1746-4fcf-bd81-cf50d5f2cbdf |
id |
ftawi:oai:epic.awi.de:48574 |
---|---|
record_format |
openpolar |
spelling |
ftawi:oai:epic.awi.de:48574 2023-05-15T14:27:07+02:00 Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska Jones, Benjamin Tape, K.D. Nitze, Ingmar Arp, Christopher D. Grosse, Guido Zimmermann, C. E. 2017-12-12 https://epic.awi.de/id/eprint/48574/ https://hdl.handle.net/10013/epic.ac03a4ee-1746-4fcf-bd81-cf50d5f2cbdf unknown Jones, B. , Tape, K. , Nitze, I. orcid:0000-0002-1165-6852 , Arp, C. D. , Grosse, G. orcid:0000-0001-5895-2141 and Zimmermann, C. E. (2017) Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska , AGU Fall Meeting, New Orleans, USA, 11 December 2017 - 15 December 2017 . hdl:10013/epic.ac03a4ee-1746-4fcf-bd81-cf50d5f2cbdf EPIC3AGU Fall Meeting, New Orleans, USA, 2017-12-11-2017-12-15 Conference notRev 2017 ftawi 2021-12-24T15:44:22Z Landscape-scale impacts of climate change in the Arctic include increases in growing season length, shrubby vegetation, winter river discharge, snowfall, summer and winter water temperatures, and decreases in river and lake ice thickness. Combined, these changes may have created conditions that are suitable for beaver colonization of low Arctic tundra regions. We developed a semi-automated workflow that analyzes Landsat imagery time series to determine the extent to which beavers may have colonized permafrost landscapes in arctic Alaska since 1999. We tested this approach on the Lower Noatak, Wulik, and Kivalina river watersheds in northwest Alaska and identified 83 locations representing potential beaver activity. Seventy locations indicated wetting trends and 13 indicated drying trends. Verification of each site using high-resolution satellite imagery showed that 80 % of the wetting locations represented beaver activity (damming and pond formation), 11 % were unrelated to beavers, and 9 % could not readily be distinguished as being beaver related or not. For the drying locations, 31 % represented beaver activity (pond drying due to dam abandonment), 62 % were unrelated to beavers, and 7 % were undetermined. Comparison of the beaver activity database with historic aerial photography from ca. 1950 and ca. 1980 indicates that beavers have recently colonized or recolonized riparian corridors in northwest Alaska. Remote sensing time series observations associated with the migration of beavers in permafrost landscapes in arctic Alaska include thermokarst lake expansion and drainage, thaw slump initiation, ice wedge degradation, thermokarst shore fen development, and possibly development of lake and river taliks. Additionally, beaver colonization in the Arctic may alter channel courses, thermal regimes, hyporheic flow, riparian vegetation, and winter ice regimes that could impact ecosystem structure and function in this region. In particular, the combination of beaver activity and permafrost dynamics may play an important role in the formation of habitats conducive to colonization by Pacific salmon. Beaver activity in arctic tundra regions may amplify the effects of climate change on permafrost landscapes and lead to landscape-scale responses not currently being considered in ecosystem models. Conference Object Arctic Arctic Climate change Ice permafrost Thermokarst Tundra wedge* Alaska Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Arctic Pacific Winter River ENVELOPE(-113.003,-113.003,64.501,64.501) |
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 |
Landscape-scale impacts of climate change in the Arctic include increases in growing season length, shrubby vegetation, winter river discharge, snowfall, summer and winter water temperatures, and decreases in river and lake ice thickness. Combined, these changes may have created conditions that are suitable for beaver colonization of low Arctic tundra regions. We developed a semi-automated workflow that analyzes Landsat imagery time series to determine the extent to which beavers may have colonized permafrost landscapes in arctic Alaska since 1999. We tested this approach on the Lower Noatak, Wulik, and Kivalina river watersheds in northwest Alaska and identified 83 locations representing potential beaver activity. Seventy locations indicated wetting trends and 13 indicated drying trends. Verification of each site using high-resolution satellite imagery showed that 80 % of the wetting locations represented beaver activity (damming and pond formation), 11 % were unrelated to beavers, and 9 % could not readily be distinguished as being beaver related or not. For the drying locations, 31 % represented beaver activity (pond drying due to dam abandonment), 62 % were unrelated to beavers, and 7 % were undetermined. Comparison of the beaver activity database with historic aerial photography from ca. 1950 and ca. 1980 indicates that beavers have recently colonized or recolonized riparian corridors in northwest Alaska. Remote sensing time series observations associated with the migration of beavers in permafrost landscapes in arctic Alaska include thermokarst lake expansion and drainage, thaw slump initiation, ice wedge degradation, thermokarst shore fen development, and possibly development of lake and river taliks. Additionally, beaver colonization in the Arctic may alter channel courses, thermal regimes, hyporheic flow, riparian vegetation, and winter ice regimes that could impact ecosystem structure and function in this region. In particular, the combination of beaver activity and permafrost dynamics may play an important role in the formation of habitats conducive to colonization by Pacific salmon. Beaver activity in arctic tundra regions may amplify the effects of climate change on permafrost landscapes and lead to landscape-scale responses not currently being considered in ecosystem models. |
format |
Conference Object |
author |
Jones, Benjamin Tape, K.D. Nitze, Ingmar Arp, Christopher D. Grosse, Guido Zimmermann, C. E. |
spellingShingle |
Jones, Benjamin Tape, K.D. Nitze, Ingmar Arp, Christopher D. Grosse, Guido Zimmermann, C. E. Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska |
author_facet |
Jones, Benjamin Tape, K.D. Nitze, Ingmar Arp, Christopher D. Grosse, Guido Zimmermann, C. E. |
author_sort |
Jones, Benjamin |
title |
Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska |
title_short |
Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska |
title_full |
Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska |
title_fullStr |
Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska |
title_full_unstemmed |
Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska |
title_sort |
landsat time series analysis documents beaver migration into permafrost landscapes of arctic alaska |
publishDate |
2017 |
url |
https://epic.awi.de/id/eprint/48574/ https://hdl.handle.net/10013/epic.ac03a4ee-1746-4fcf-bd81-cf50d5f2cbdf |
long_lat |
ENVELOPE(-113.003,-113.003,64.501,64.501) |
geographic |
Arctic Pacific Winter River |
geographic_facet |
Arctic Pacific Winter River |
genre |
Arctic Arctic Climate change Ice permafrost Thermokarst Tundra wedge* Alaska |
genre_facet |
Arctic Arctic Climate change Ice permafrost Thermokarst Tundra wedge* Alaska |
op_source |
EPIC3AGU Fall Meeting, New Orleans, USA, 2017-12-11-2017-12-15 |
op_relation |
Jones, B. , Tape, K. , Nitze, I. orcid:0000-0002-1165-6852 , Arp, C. D. , Grosse, G. orcid:0000-0001-5895-2141 and Zimmermann, C. E. (2017) Landsat time series analysis documents beaver migration into permafrost landscapes of arctic Alaska , AGU Fall Meeting, New Orleans, USA, 11 December 2017 - 15 December 2017 . hdl:10013/epic.ac03a4ee-1746-4fcf-bd81-cf50d5f2cbdf |
_version_ |
1766300712639135744 |