Climate Change Hotspots Identification in China through the CMIP5 Global Climate Model Ensemble

Huanghe Gu,Chuanguo Yang,Chuanhao Fan,Zhongbo Yu,Qin Ju,Jigan Wang

doi:10.1155/2014/963196

Abstract

China is one of the countries vulnerable to adverse climate changes. The potential climate change hotspots in China throughout the 21st century are identified in this study by using a multimodel, multiscenario climate model ensemble that includes Phase Five of the Coupled Model Intercomparison Project (CMIP5) atmosphere-ocean general circulation models. Both high (RCP8.5) and low (RCP4.5) greenhouse gas emission trajectories are tested, and both the mean and extreme seasonal temperature and precipitation are considered in identifying regional climate change hotspots. Tarim basin and Tibetan Plateau in West China are identified as persistent regional climate change hotspots in both the RCP4.5 and RCP8.5 scenarios. The aggregate impacts of climate change increase throughout the 21st century and are more significant in RCP8.5 than in RCP4.5. Extreme hot event and mean temperature are two climate variables that greatly contribute to the hotspots calculation in all regions. The contribution of other climate variables exhibits a notable subregional variability. South China is identified as another hotspot based on the change of extreme dry event, especially in SON and DJF, which indicates that such event will frequently occur in the future. Our results can contribute to the designing of national and cross-national adaptation and mitigation policies.

Highlights

Global warming in the late 20th century has been primarily attributed to the anthropogenic greenhouse gas (GHG) emissions
According to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), the average global warming is measured at 0.74∘C (0.56∘C to 0.92∘C) over the last hundred years (1906 to 2005)
The relative aggregate climate change that is reflected by standard Euclidean distance (SED) increases over time and across different scenarios because of its dependence on GHG emissions and concentrations

Summary

Introduction

Global warming in the late 20th century has been primarily attributed to the anthropogenic greenhouse gas (GHG) emissions. For countries with large territory like China, it is important to assess local climate change impacts and to plan national policies response to global warming. Advances in Meteorology for quantitatively exploring these regions, climate change hotspots can be identified based on projected changes in temperature and precipitation. RCCI is a comparative index that identifies the hotspot regions that will reveal the greatest relative changes in these variables [21]. Williams et al [24] developed the standard Euclidean distance (SED) to measure the relative responses of different regions to GHGinduced global warming. The implementation of CMIP5 has paved the way for a new generation of global climate model simulations that can identify climate change hotspots and yield highly reliable projections [26,27,28].

Data and Methodology

Results

Conclusions and Discussion