Observed soil temperature trends associated with climate change in the Tibetan Plateau, 1960–2014

Abstract

Soil temperature, an important indicator of climate change, has rarely explored due to scarce observations, especially in the Tibetan Plateau (TP) area. In this study, changes observed in five meteorological variables obtained from the TP between 1960 and 2014 were investigated using two non-parametric methods, the modified Mann-Kendall test and Sen's slope estimator method. Analysis of annual series from 1960 to 2014 has shown that surface (0 cm), shallow (5-20 cm), deep (40-320 cm) soil temperatures (ST), mean air temperature (AT), and precipitation (P) increased with rates of 0.47°C/decade, 0.36°C/decade, 0.36°C/decade, 0.35°C/decade, and 7.36 mm/decade, respectively, while maximum frozen soil depth (MFD) as well as snow cover depth (MSD) decreased with rates of 5.58 and 0.07 cm/decade. Trends were significant at 99 or 95% confidence level for the variables, with the exception of P and MSD. More impressive rate of the ST at each level than the AT indicates the clear response of soil to climate warming on a regional scale. Monthly changes observed in surface ST in the past decades were consistent with those of AT, indicating a central place of AT in the soil warming. In addition, with the exception of MFD, regional scale increasing trend of P as well as the decreasing MSD also shed light on the mechanisms driving soil trends. Significant negative-dominated correlation coefficients (α = 0.05) between ST and MSD indicate the decreasing MSD trends in TP were attributable to increasing ST, especially in surface layer. Owing to the frozen ground, the relationship between ST and P is complicated in the area. Higher P also induced higher ST, while the inhibition of freeze and thaw process on the ST in summer. With the increasing AT, P accompanied with the decreasing MFD, MSD should be the major factors induced the conspicuous soil warming of the TP in the past decades.

Carbon and Water Use Efficiencies: A Comparative Analysis of Ten Terrestrial Ecosystem Models under Changing Climate

“…We note that models soil temperature respond to climate driver (Fig. S8a) is consistent with the observed increase in soil temperature across the globe 41–45 . The decrease in models’ temperature (except LPJ-wsl and GTEC) due to CO 2 fertilization (Fig.…”

The Relationship Between Air and Soil Temperature as a Local Indicator of Climate Change in a Small Agricultural Catchment

“…Depending on the depth of soil and its coverage, soil temperature is connected to basic meteorological elements, such as: air temperature, solar radiation intensity and precipitation (Oni et al, 2017;Fang et al, 2019, Bryś, 2008Wojtkowski andSkower, 2017, Szyga-Pluta, 2018). The average soil temperature at the Czarna station varies depending on the depth of the soil profile.…”

Response of shallow soil temperature to climate change on the Qinghai–Tibetan Plateau

“…Zhu et al (2018) investigated the spatiotemporal variations in shallow soil temperature at depths of 0-40 cm during 1983-2013 but only focused on the annual scale. Fang et al (2019) estimated the changes in the surface (0 cm), shallow (5-20 cm), and deep (40-320 cm) soil temperatures, but the analysis on the influencing factors of spatial distribution and temporal variation in soil temperature is insufficient, especially regarding the influence of snow cover on soil temperature. The present study primarily aims to (a) investigate the spatial distributions of shallow soil temperature (0-20 cm) on the QTP based on the 30-year climate normal at annual and seasonal scales, (b) estimate the changes in shallow soil temperature (0-20 cm) in the past 50 years (from 1965 to 2014), and (c) analyse the potential impact of climate change on soil temperature.…”