Response of Precipitation in Tianshan to Global Climate Change Based on the Berkeley Earth and ERA5 Reanalysis Products

Mengtian Fan,Jianhua Xu,Yaning Chen,Dahui Li

doi:10.3390/rs14030519

Abstract

Global climate change has readjusted a global-scale precipitation distribution in magnitude and timing. In mountainous areas, meteorological stations and observation data are very limited, making it difficult to accurately understand the response of precipitation to global climate change. Based on ECMWF Reanalysis v5 precipitation products, Berkeley Earth global temperature, and typical atmospheric circulation indexes, we integrated a gradient descent-nonlinear regression downscaling model, cross wavelet transform, and wavelet correlation method to analyze the precipitation response in Tianshan to global climate change. This study provides a high-resolution (90 m × 90 m) precipitation dataset in Tianshan and confirms that global warming, the North Pacific Pattern (NP), the Western Hemisphere Warm Pool (WHWP), and the Atlantic Multidecadal Oscillation (AMO) are related to the humidification of Tianshan over the past 40 years. The precipitation in Tianshan and global temperature have a resonance period of 8–15 months, and the correlation coefficient is above 0.9. In Tianshan, spring precipitation is determined mainly by AMO, North Tropical Atlantic Sea Level Temperature, Pacific Interdecadal Oscillation (PDO), Tropical North Atlantic Index, WHWP, NP, summer by NP, North Atlantic Oscillation, and PDO, autumn by AMO, and winter by Arctic Oscillation. This research can serve the precipitation forecast of Tianshan and help in the understanding of the regional response to global climate change.

Highlights

Large increases in surface temperature have been detected over the past few decades [1].With global warming, global average precipitation has shown an increasing trend [2]
In order to understand the response of precipitation to global climate change in different regions, this study divided the study area into West Tianshan (WTS) (73◦ 540 E–81◦ 180 E), Central Tianshan (CTS) (81◦ 180 E–87◦ 300 E), and Eastern Tianshan (ETS) (87◦ 300 E–95◦ 180 E) (Figure 1) [65]
Global climate change has an important impact on regional precipitation changes, and this study confirmed it

Summary

Introduction

Large increases in surface temperature have been detected over the past few decades [1].With global warming, global average precipitation has shown an increasing trend [2]. Large increases in surface temperature have been detected over the past few decades [1]. Wentz et al [3] reported that global mean precipitation increased at a rate of approximately 7.4%. 9.7% per 1 ◦ C of surface warming [4]. Global warming has exacerbated the uncertainty of regional precipitation changes [5,6,7]. Over the past three decades, the differences in seasonal precipitation have become more pronounced [8], and the spatial distributions of precipitation have changed [9]. The difference between dry and wet regions expanded [10,11,12], and significant changes in wet-day frequencies and consecutive dry days have been identified [13]. Climate models [14] and observations [15,16]

Methods

Results

Discussion

Conclusion