Permafrost zonation index map and statistics over the Qinghai–Tibet Plateau based on field evidence

Permafrost is prevalent over the Qinghai–Tibet Plateau (QTP), but mapping its distribution is challenging due to the limited availability of ground‐truth data sets and strong spatial heterogeneity in the region. Based on a recently developed inventory of permafrost presence or absence from 1475 in s...

Full description

Saved in:
Bibliographic Details
Published in:Permafrost and periglacial processes 2019-07, Vol.30 (3), p.178-194
Main Authors: Cao, Bin, Zhang, Tingjun, Wu, Qingbai, Sheng, Yu, Zhao, Lin, Zou, Defu
Format: Article
Language:English
Subjects:
Air temperature
Distribution
Glacial lakes
Glaciers
Heterogeneity
In situ measurement
Lakes
Mapping
Mathematical models
mountians
Patchiness
Permafrost
Permafrost distribution
permafrost zonation index
Plant cover
Qinghai‐Tibet Plateau
Remote sensing
Snow cover
Spatial data
Spatial heterogeneity
Spatial variability
Spatial variations
Statistical analysis
Statistical methods
Statistical models
Surface-air temperature relationships
Vegetation cover
Zonation
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Permafrost is prevalent over the Qinghai–Tibet Plateau (QTP), but mapping its distribution is challenging due to the limited availability of ground‐truth data sets and strong spatial heterogeneity in the region. Based on a recently developed inventory of permafrost presence or absence from 1475 in situ observations, we developed and trained a statistical model and used it to compile a high‐resolution (30 arc‐seconds) permafrost zonation index (PZI) map. The PZI model captures the high spatial variability of permafrost distribution over the QTP because it considers multiple controlling variables, including near‐surface air temperature downscaled from re‐analysis, snow cover days and vegetation cover derived from remote sensing. Our results showed the new PZI map achieved the best performance compared to available existing PZI and traditional categorical maps. Based on more than 1000 in situ measurements, the Cohen's kappa coefficient and overall classification accuracy were 0.62 and 82.5%, respectively. Excluding glaciers and lakes, the area of permafrost regions over the QTP is approximately 1.54 (1.35–1.66) ×106 km2, or 60.7 (54.5–65.2)% of the exposed land, while area underlain by permafrost is about 1.17 (0.95–1.35) ×106 km2, or 46 (37.3–53.0)%.
ISSN:1045-6740
1099-1530
DOI:10.1002/ppp.2006