Post-fire stabilization of thaw-affected permafrost terrain in northern Alaska
Post-fire stabilization of thaw-affected permafrost terrain in northern Alaska
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阿拉斯加北部受解冻影响的永久冻土地形的火灾后稳定
DOI：
10.1038/s41598-024-58998-5
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发表时间：
2024
影响因子：
4.6
通讯作者：
Jandt, Randi
中科院分区：
文献类型：
--
作者：
Jones, Benjamin M.;Kanevskiy, Mikhail Z.;Shur, Yuri;Gaglioti, Benjamin V.;Jorgenson, M. Torre;Ward Jones, Melissa K.;Veremeeva, Alexandra;Miller, Eric A.;Jandt, Randi
2007年，阿纳克图武克河大火烧毁了阿拉斯加北部超过1,000平方公里的北极冻土带，其中50%发生在富含冰的同生永久冻土( )地区。到2014年，伊多玛地区的冰楔普遍退化。在50平方公里的区域内，在2009年和2014年获得的重复机载LiDAR数据中，探测到15%的陆地面积出现融化沉降。2021年航空激光雷达数据集的更新观测表明，在研究区域的1%的<； 检测到了额外的融化下沉，这表明受融化影响的永久冻土地形是稳定的。2010年至2015年的地温测量表明，烧毁地的近地表土壤融化日数比未烧毁的对照地多3 × ，但到2022年，这一数字减少到1.3 × 。近地表多年冻土的年平均地面温度在火灾后7年前在烧伤现场增加了0.33℃/年，但在随后的8年里冷却了0.15℃/年，而对照地点的温度保持相对稳定。从冰楔槽(n = 41)和多边形中心(n = 8)采集的多年冻土芯显示存在融化不整合，大多数情况下被恢复的多年冻土层覆盖，平均分别为14.2m和18.3m。综上所述，我们的观察结果突出表明，在阿纳克图武克河冻土带大火之后，富含冰的永久冻土开始退化，随后是一段解冻停止、永久冻土堆积和地形稳定的时期。
In 2007, the Anaktuvuk River fire burned more than 1000 km2of arctic tundra in northern Alaska, ~ 50% of which occurred in an area with ice-rich syngenetic permafrost (Yedoma). By 2014, widespread degradation of ice wedges was apparent in the Yedoma region. In a 50 km2area, thaw subsidence was detected across 15% of the land area in repeat airborne LiDAR data acquired in 2009 and 2014. Updating observations with a 2021 airborne LiDAR dataset show that additional thaw subsidence was detected in < 1% of the study area, indicating stabilization of the thaw-affected permafrost terrain. Ground temperature measurements between 2010 and 2015 indicated that the number of near-surface soil thawing-degree-days at the burn site were 3 × greater than at an unburned control site, but by 2022 the number was reduced to 1.3 × greater. Mean annual ground temperature of the near-surface permafrost increased by 0.33 °C/yr in the burn site up to 7-years post-fire, but then cooled by 0.15 °C/yr in the subsequent eight years, while temperatures at the control site remained relatively stable. Permafrost cores collected from ice-wedge troughs (n = 41) and polygon centers (n = 8) revealed the presence of a thaw unconformity, that in most cases was overlain by a recovered permafrost layer that averaged 14.2 cm and 18.3 cm, respectively. Taken together, our observations highlight that the initial degradation of ice-rich permafrost following the Anaktuvuk River tundra fire has been followed by a period of thaw cessation, permafrost aggradation, and terrain stabilization.
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影响因子：
4.9
作者：
J. McCarty;J. Aalto;Ville-Veikko Paunu;S. Arnold;S. Eckhardt;Z. Klimont;J. Fain;N. Evangeliou-
通讯作者：
J. McCarty;J. Aalto;Ville-Veikko Paunu;S. Arnold;S. Eckhardt;Z. Klimont;J. Fain;N. Evangeliou-
影响因子：
30.7
作者：
Chen, Yang;Romps, David M.;Randerson, James T.
通讯作者：
Randerson, James T.
影响因子：
7.2
作者：
A. McGuire;R. Macdonald;E. Schuur;J. Harden;P. Kuhry;D. Hayes;T. Christensen;M. Heimann
通讯作者：
M. Heimann
美国阿拉斯加北极坡未记录的苔原火灾
影响因子：
--
作者：
Miller, Eric A.;Jones, Benjamin M.;Baughman, Carson A.;Jandt, Randi R.;Jenkins, Jennifer L.;Yokel, David A.
通讯作者：
Yokel, David A.
影响因子：
11.6
作者：
Chen, Yaping;Hu, Feng S.;Lara, Mark J.
通讯作者：
Lara, Mark J.