In recent years, climate change has been aggravated in many regions of the wodd. The Hexi Corridor is located in the semiarid climate zone of Northwest China, which is parUculady affected by climate change. Climate ch...In recent years, climate change has been aggravated in many regions of the wodd. The Hexi Corridor is located in the semiarid climate zone of Northwest China, which is parUculady affected by climate change. Climate change has led to the spatial and temporal variations of temperature and precipitation, which may result in hydrological drought and water shortage. Thus, it is necessary to explore and assess the drought characteristics of river systems in this area. The patterns of hydrological drought in the Hexi Corridor were identified using the streamflow drought index （SDI） and standardized precipitation index at 12-month timescale （SPI12） from 1960 to 2013. The evolution of drought was obtained by the Mann-Kendall test and wavelet transform method. The results showed that both the mean annual SDI and SPI12 series in the Hexi Corridor exhibited an increasing trend during the study period. According to the results of wavelet analysis, we divided the study period into two segments, i.e. before and after 1990. Before 1990, the occurrence of droughts showing decreased SDI and SPI12 was concentrated in the northern part of the corridor and shifted to the eastern part of the corridor after 1990. The probability of drought after 1990 in Shule River basin decreased while increased in Shiyang River basin. The wavelet analysis results showed that Shiyang River basin will be the first area to go through the next drought period. Additionally, the relationships between drought pattern and climate indices were analyzed. The enhanced westedy winds and increased precipitation and glacier runoff were the main reasons of wet trend in the Hexi Corridor. However, the uneven spatial variations of precipitation, temperature and glacier runoff led to the difference of hydrological drought variations between the Shule, Heihe and Shiyang River basins.展开更多
The link between climate and war has long been a topic of great scientific and social interest.In this study,we investigate the influence of climate on warfare in China’s Hexi Corridor region since 241 A.D.Using the ...The link between climate and war has long been a topic of great scientific and social interest.In this study,we investigate the influence of climate on warfare in China’s Hexi Corridor region since 241 A.D.Using the superposed epoch analysis of tree-ring data and historical war data,we observe a notable correlation between interannual dry-wet variations and wars instigated by nomadic groups in the Hexi Corridor.However,this relationship is dynamic and influenced by the region’s relative unity.During periods in which the Hexi Corridor was ruled by multiple regimes,wars tended to follow dry climatic conditions,which may be due to the fact that unusual drought during these periods likely heightened competition for resources and land.Conversely,during times of regional unity,wars were more likely to occur when climatic conditions were wet because the expansion of rangelands and the accumulation of resources helped fuel the nomads’outward conquest.These findings underscore the complexity of the relationship between war and climate change.To gain a more comprehensive understanding of this relationship,continuous,high-resolution historical temperature and humidity datasets with broader and more uniform coverage are needed across multiple regions.In addition,collecting and examining disaggregated historical war data for regions with distinct characteristics is essential.展开更多
基金supported by the National Natural Science Foundation of China(91125005,41271083,41201062)the Incubation Foundation for Special Disciplines of the National Natural Science Foundation of China(J1210003/J0109)the Open Fund Project of the State Key Laboratory of Frozen Soil Engineering of China(SKLFSE201412)
文摘In recent years, climate change has been aggravated in many regions of the wodd. The Hexi Corridor is located in the semiarid climate zone of Northwest China, which is parUculady affected by climate change. Climate change has led to the spatial and temporal variations of temperature and precipitation, which may result in hydrological drought and water shortage. Thus, it is necessary to explore and assess the drought characteristics of river systems in this area. The patterns of hydrological drought in the Hexi Corridor were identified using the streamflow drought index （SDI） and standardized precipitation index at 12-month timescale （SPI12） from 1960 to 2013. The evolution of drought was obtained by the Mann-Kendall test and wavelet transform method. The results showed that both the mean annual SDI and SPI12 series in the Hexi Corridor exhibited an increasing trend during the study period. According to the results of wavelet analysis, we divided the study period into two segments, i.e. before and after 1990. Before 1990, the occurrence of droughts showing decreased SDI and SPI12 was concentrated in the northern part of the corridor and shifted to the eastern part of the corridor after 1990. The probability of drought after 1990 in Shule River basin decreased while increased in Shiyang River basin. The wavelet analysis results showed that Shiyang River basin will be the first area to go through the next drought period. Additionally, the relationships between drought pattern and climate indices were analyzed. The enhanced westedy winds and increased precipitation and glacier runoff were the main reasons of wet trend in the Hexi Corridor. However, the uneven spatial variations of precipitation, temperature and glacier runoff led to the difference of hydrological drought variations between the Shule, Heihe and Shiyang River basins.
基金supported by the Basic Science Center for Tibetan Plateau Earth System(Grant No.41988101)the National Natural Science Foundation of China(Grant No.41977392)+2 种基金the National Key R&D Program of China(Grant No.2019YFA0606602)the Natural Science Foundation of Gansu,China(Grant No.22JR5RA449)the Fundamental Research Funds for Central Universities(Grant No.22lzujbkydx036)。
文摘The link between climate and war has long been a topic of great scientific and social interest.In this study,we investigate the influence of climate on warfare in China’s Hexi Corridor region since 241 A.D.Using the superposed epoch analysis of tree-ring data and historical war data,we observe a notable correlation between interannual dry-wet variations and wars instigated by nomadic groups in the Hexi Corridor.However,this relationship is dynamic and influenced by the region’s relative unity.During periods in which the Hexi Corridor was ruled by multiple regimes,wars tended to follow dry climatic conditions,which may be due to the fact that unusual drought during these periods likely heightened competition for resources and land.Conversely,during times of regional unity,wars were more likely to occur when climatic conditions were wet because the expansion of rangelands and the accumulation of resources helped fuel the nomads’outward conquest.These findings underscore the complexity of the relationship between war and climate change.To gain a more comprehensive understanding of this relationship,continuous,high-resolution historical temperature and humidity datasets with broader and more uniform coverage are needed across multiple regions.In addition,collecting and examining disaggregated historical war data for regions with distinct characteristics is essential.
