No Significant Shift of Warming Trend over the Last Two Decades on the Mid-South of Tibetan Plateau

Li Li,Qi Qi,Zhang Zhang,Ding Ding,Wang Wang,Liu Liu

doi:10.3390/atmos10070416

Abstract

Climate warming on the Tibetan Plateau has been regarded as an important driving force of regional environmental change. Although several studies have analyzed the shift of warming trends on this plateau within the context of a recent global warming “hiatus” since 1998, their disparate findings have hindered a comprehensive and regional understanding. Based on the daily mean temperature (Tmean), maximum temperature (Tmax), and minimum temperature (Tmin) collected from meteorological stations on the period of 1961–2017, we re-examined the timing and magnitude of temperature phase change using piecewise linear regression on the mid-south of Tibetan Plateau. The results show that among the trends in regional annual Tmean, Tmax and Tmin, the statistically significant change-point was observed only in annual Tmax (p < 0.01). The warming trend of annual Tmax has accelerated significantly since 1992 and has exceeded that of annual Tmin after 2000, causing a remarkable reversal from decline to increase in diurnal temperature range (DTR) (p < 0.01). Spatially, the occurrence time of change-points in Tmean, Tmax, and Tmin varied among stations, but most of them occurred before the mid-1990s. Besides, the trend shifts in Tmax/DTR during the cold season played a primary role in the significant trend shifts in annual Tmax/DTR. This study underscores that there is no significant shift of warming trends over the last two decades on the mid-south of Tibetan Plateau.

Highlights

The global surface climate is warming inexorably but unevenly [1]
The rates of warming in annual Tmean, Tmax, and Tmin calculated based on data from the 17 stations were 0.34, 0.31, and 0.43 ◦ C/decade, respectively (Table 1). This result indicates that the rate of increase on the mid-south of Tibetan Plateau was highest for Tmin, followed by Tmean, and the rate of increase was lowest for Tmax
Our study re-examined the existence of significant shifts in temperature trend on the mid-south of Tibetan Plateau during 1961–2017

Summary

Introduction

The global surface climate is warming inexorably but unevenly [1]. The rates in climate warming appeared spatial heterogeneous, and the shifts in regional temperature trends are asynchronous with that of global-averaged temperature [2,3]. Mounting studies have provided evidence that high mountains experienced stronger warming than their lower-elevation counterparts over the past several decades [4,5], resulting in serious effects on alpine ecosystems and downstream [6]. The spatial and temporal variability of warming in high elevation areas has been attracting increasing attention [5,7]. Climate change in the Tibetan Plateau, the highest and largest plateau in the world, is widely regarded to be the driving force for both regional environmental change and the amplification of environmental changes throughout the world [8,9].

Objectives

Results

Discussion

Conclusion