Mountain glaciers are highly sensitive to climate change. In this paper, we systematically analyzed and discussed the responses of glaciers to climate change during 1960–2017 in western China by the methods of least ...Mountain glaciers are highly sensitive to climate change. In this paper, we systematically analyzed and discussed the responses of glaciers to climate change during 1960–2017 in western China by the methods of least squares and correlation analysis. Results show that the maximum temperature, minimum temperature, average temperature, and precipitation significantly increased in western China at the rates of 0.32°C/10 a, 0.48°C/10 a, 0.39°C/10 a, and 11.20 mm/10 a, respectively. However, the wind speed, hours of sunshine, snowfall, and snowy days displayed decreasing trends at the rates of –0.53 m/(s·10 a), 3.72 h/10 a, –2.90 mm/10 a, and –0.10 d/10 a, respectively. The annual percentage of glacier area decreased by approximately 0.42%, and the average glacier area decreased by 2.76 km^2/a. Meanwhile, glacial shrinkages were greater in the Altay Mountains, Tanggula Mountains, and Qilian Mountains than in the other mountainous regions. Glacier accumulation decreased while melt volume increased at a rate of 2.7×10~4 m^3/a. The area of melt volume was 1.3 times that of the glacier accumulation area. The glacier mass balance(GMB) decreased substantially at a rate of –14.0 mm/a, whereas the equilibrium line altitude(ELA) showed an increasing trend at a rate of 0.5 mm/a. After 1997, the mass was smaller than –500.0 mm, indicating a huge loss in glaciers. Furthermore, relationships between ELA and GMB and various climatic factors were established. Temperature and precipitation demonstrated a significantly negative correlation, whereas wind speed and snowy days had significantly positive correlations with GMB. Snowy days also exhibited a remarkably negative correlation with ELA. The strong warming trend and less snowy days were thought to be the main factors leading to glacial melting, whereas the increase in precipitation, and reductions of sunshine hours and wind speed might slow glacial melting.展开更多
探讨了近3000年来长江中游西部洪水灾害发展的人文因素。古代(3 000-700 a B P)人口较少,多择地势高的岗地居住,只有少数沿江城市需要堤防保护;长江干流洪水可多处分道散流,所携带泥沙导致云梦泽解体消亡。自宋代开始,低地筑垸围湖,与...探讨了近3000年来长江中游西部洪水灾害发展的人文因素。古代(3 000-700 a B P)人口较少,多择地势高的岗地居住,只有少数沿江城市需要堤防保护;长江干流洪水可多处分道散流,所携带泥沙导致云梦泽解体消亡。自宋代开始,低地筑垸围湖,与水争地,但九穴十三口畅通,洪水灾害不严重。明代(700-450 a B P)几乎完全堵塞了荆江北流的穴口,荆北大堤联成一体,但堤防薄弱,出现过30次决口成灾。清代以来,随着人口激增,与水争地矛盾加剧,堤防加高培厚,使荆江河道洪水位大幅度上升,溃堤和溃坝洪水灾害较明代成倍出现。同时,历代的“舍南保北”政策迫使长江干流大洪水中过半水量与泥沙向南泄入洞庭湖,曾使洞庭湖面积扩至6 000 km2,以后洞庭湖迅速淤积萎缩。1949至1985年间,人口又一次迅速增长,进一步加强围湖垦殖,大量通江湖泊面积萎缩。除1954和1998年那样人所共知的严重洪水灾害外,内涝渍水灾害也非常严重,人类与洪水的矛盾达到了顶点。改革开放后,尤其是三峡大坝的修建,极大地改变了长江中游的水文情势,工业化与城市化的迅猛发展,农村人口压力减轻,而21世纪初期降水相对较少,因此当前相当一段时间长江中游洪水灾害大为缓和。应抓住时机,总结经验,在人地和谐的现代水科学技术理念指导下,制定21世纪前半期,特别是2020年前的长江水利和水资源发展规划,促使人与洪水和谐共处。展开更多
基金supported by the National Natural Science Foundation of China (41771048, 41571076)the National Social Science Foundation of China (15XZZ012)+2 种基金the Key Lab Project of Shaanxi Province of China (13JS010)the Baoji University of Arts and Science Project (ZK16061)the Baoji University of Arts and Science Geography Key Discipline Project
文摘Mountain glaciers are highly sensitive to climate change. In this paper, we systematically analyzed and discussed the responses of glaciers to climate change during 1960–2017 in western China by the methods of least squares and correlation analysis. Results show that the maximum temperature, minimum temperature, average temperature, and precipitation significantly increased in western China at the rates of 0.32°C/10 a, 0.48°C/10 a, 0.39°C/10 a, and 11.20 mm/10 a, respectively. However, the wind speed, hours of sunshine, snowfall, and snowy days displayed decreasing trends at the rates of –0.53 m/(s·10 a), 3.72 h/10 a, –2.90 mm/10 a, and –0.10 d/10 a, respectively. The annual percentage of glacier area decreased by approximately 0.42%, and the average glacier area decreased by 2.76 km^2/a. Meanwhile, glacial shrinkages were greater in the Altay Mountains, Tanggula Mountains, and Qilian Mountains than in the other mountainous regions. Glacier accumulation decreased while melt volume increased at a rate of 2.7×10~4 m^3/a. The area of melt volume was 1.3 times that of the glacier accumulation area. The glacier mass balance(GMB) decreased substantially at a rate of –14.0 mm/a, whereas the equilibrium line altitude(ELA) showed an increasing trend at a rate of 0.5 mm/a. After 1997, the mass was smaller than –500.0 mm, indicating a huge loss in glaciers. Furthermore, relationships between ELA and GMB and various climatic factors were established. Temperature and precipitation demonstrated a significantly negative correlation, whereas wind speed and snowy days had significantly positive correlations with GMB. Snowy days also exhibited a remarkably negative correlation with ELA. The strong warming trend and less snowy days were thought to be the main factors leading to glacial melting, whereas the increase in precipitation, and reductions of sunshine hours and wind speed might slow glacial melting.
文摘探讨了近3000年来长江中游西部洪水灾害发展的人文因素。古代(3 000-700 a B P)人口较少,多择地势高的岗地居住,只有少数沿江城市需要堤防保护;长江干流洪水可多处分道散流,所携带泥沙导致云梦泽解体消亡。自宋代开始,低地筑垸围湖,与水争地,但九穴十三口畅通,洪水灾害不严重。明代(700-450 a B P)几乎完全堵塞了荆江北流的穴口,荆北大堤联成一体,但堤防薄弱,出现过30次决口成灾。清代以来,随着人口激增,与水争地矛盾加剧,堤防加高培厚,使荆江河道洪水位大幅度上升,溃堤和溃坝洪水灾害较明代成倍出现。同时,历代的“舍南保北”政策迫使长江干流大洪水中过半水量与泥沙向南泄入洞庭湖,曾使洞庭湖面积扩至6 000 km2,以后洞庭湖迅速淤积萎缩。1949至1985年间,人口又一次迅速增长,进一步加强围湖垦殖,大量通江湖泊面积萎缩。除1954和1998年那样人所共知的严重洪水灾害外,内涝渍水灾害也非常严重,人类与洪水的矛盾达到了顶点。改革开放后,尤其是三峡大坝的修建,极大地改变了长江中游的水文情势,工业化与城市化的迅猛发展,农村人口压力减轻,而21世纪初期降水相对较少,因此当前相当一段时间长江中游洪水灾害大为缓和。应抓住时机,总结经验,在人地和谐的现代水科学技术理念指导下,制定21世纪前半期,特别是2020年前的长江水利和水资源发展规划,促使人与洪水和谐共处。