Evaluation of Land Surface Phenology in Northern Hemisphere Permafrost Regions

被引：0

作者：

Zhao, Yaohua ^{[1
]}

Peng, Xiaoqing ^{[1
,2
]}

Frauenfeld, Oliver W. ^{[3
]}

Cui, Xia ^{[1
]}

Bi, Jian ^{[1
]}

Ma, Xuanlong ^{[1
]}

Wei, Gang ^{[1
]}

Mu, Cuicui ^{[1
,2
]}

Sun, Hao ^{[4
]}

Sui, Jia ^{[4
]}

机构：

[1] Lanzhou Univ, Coll Earth & Environm Sci, Key Lab Western Chinas Environm Syst, Minist Educ, Lanzhou, Peoples R China

[2] Lanzhou Univ, Observat & Res Stn Ecoenvironm Frozen Ground Qilia, Lanzhou, Peoples R China

[3] Texas A&M Univ, Dept Geog, College Stn, TX USA

[4] Qinghai Prov Geol Disaster Prevent & Control Tech, Qinghai Prov Gen Geol & Environm Monitoring Stn, Xining, Peoples R China

来源：

JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES | 2024年 / 129卷 / 05期

基金：

中国国家自然科学基金; 国家重点研发计划;

关键词：

land surface phenology; cold region ecology; remote sensing; permafrost regions; ENHANCED VEGETATION INDEX; DELAYED SPRING PHENOLOGY; GREEN-UP DATES; TIBETAN PLATEAU; TIME-SERIES; TEMPORAL RESOLUTION; HIGH-LATITUDES; SNOW COVER; NDVI DATA; MODIS;

D O I：

10.1029/2023JG007951

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

Vegetation phenology interacts strongly with climate through the exchange of carbon, water, momentum, and energy between terrestrial ecosystem and atmosphere. These vegetation dynamics in Northern Hemisphere permafrost regions have substantial uncertainties in previous studies, partly due to differences in datasets. Thus, reliable land surface phenology (LSP) retrievals are crucial for understanding the effects of climate change on ecosystems and biosphere-atmosphere-hydrosphere interactions. We assessed various LSP datasets at different spatial resolutions for 2001-2014, generated by different methods based on different satellite observations. We also assessed the accuracy of LSP by comparing with CO2 flux phenology. For start of growing season (SOS), the comprehensive evaluation indicated MODIS phenology showed better consistency and higher accuracy with flux-derived phenology observations (R = 0.54, RMSE = 36.2 days, bias<5 days). For end of growing season (EOS), we cannot conclusively determine which LSP performs best. In the Northern Hemisphere permafrost regions, SOS occurred at 100-150 days (April-May), and EOS occurred at 260-320 days (September-November). During 2001-2014, SOS occurred earlier by 0.33 +/- 0.30 days/yr. Significant trends were observed for 6.4%-27.6% of pixels, averaging -1.30 +/- 1.16 days/yr. EOS occurred earlier by 0.25 +/- 0.43 days/yr, with significant trends averaging -0.52 +/- 0.94 days/yr. Among LSPs, variability in EOS trends was significant, with even the direction of trends differing. This study may provide insights into LSP data selection and further understanding of vegetation dynamics and its mechanisms in permafrost regions.

引用

页数：24