The Risk of the Population in a Changing Climate over the Tibetan Plateau, China: Integrating Hazard, Population Exposure and Vulnerability

Qin Ji,Jianping Yang,Qingshan He,Hongju Chen,Can Wang,Quntao Duan,Zhenqi Sun,Yao Li

doi:10.3390/su13073633

Abstract

As the “Third Pole” of the Earth, the Tibetan Plateau (TP) has been warming significantly, and the instability of extreme events related to climate and weather has enhanced exceptionally in recent decades. These changes have posed increasingly severe impacts on the population over the TP. So far, however, the impacts on the population have not been assessed systematically and comprehensively from the perspective of risk. In this paper, the hazard of climate change was assessed from a fresh look, not only considering extreme changes of air temperature, precipitation, and wind speed, but also their changes in mean and fluctuation, using daily meteorological data from 1961–2015. The population exposure and vulnerability to climate change were then evaluated using demographic data and considering population scale and structure. Finally, the population risk over the TP to climate change was quantitatively assessed within the framework of the Intergovernmental Panel on Climate Change (IPCC). The results showed that the climate change hazard was mainly at medium and heavy levels, in areas accounting for 64.60% of the total. The population exposure was relatively low; the land area at slight and light levels accounted for 83.94%, but high in the eastern edge area of the TP. The population vulnerability was mostly at medium and heavy levels, and the non-agricultural population rate was the key factor affecting the population vulnerability. Generally, the overall population risk over the TP was not very high: the number of counties with heavy and very heavy risk only accounted for 24.29%, and land area was less than 5%. However, more than 40% of the population was in high-risk areas, located in the eastern edge area of the TP. Population exposure was the decisive factor of the population risk to climate change, and high population exposure might lead to high risk. These findings were potentially valuable to improve cognition of risk, develop proactive risk mitigation strategies, and ensure sustainable development.

Highlights

According to the definition of climate change hazard, the temperature, precipitation, and wind speed were selected as the factors to characterize the variations of the climate system, because it is impossible to include all the factors into the climate change hazard assessment, and it is necessary to take into account the patterns and degrees of disturbance and harm caused by different factors to the population
Pearson correlation analysis was used to reveal the relationship between population risk and its influencing factors, and the results showed that the hazard, population exposure, and vulnerability were negatively correlated (Table 8)
Our study found that the spatial variation of the population exposure over the Tibetan Plateau (TP) was much significant than the spatial variation of the hazard and vulnerability, and the population exposure has a greater impact on risk, which agrees with some existing studies on the TP or other areas [52,71]

Summary

Introduction

In the past few decades, most regions have experienced obvious warming, with a global average combined land and ocean surface temperature increase of 0.85 ◦ C (0.65–1.06 ◦ C). In China, the temperature of the land area increased by 0.90–1.52 ◦ C from 1913 to 2012 [5], which was obviously higher than the global increase rate, and the overall tendency of precipitation showed no significant. Sustainability 2021, 13, 3633 increase or decrease [6,7] How much impact these climate factors have affected humans and what adaptation measures should be taken have been hotspots of global climate change research [8,9,10,11,12,13,14]

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Results

Conclusion