The Chenab basin is located in northwest India and eastern Pakistan.Glaciers in Chenab basin,as local freshwater resources,are very important to the regional ecological environment and development.At the same time,SBA...The Chenab basin is located in northwest India and eastern Pakistan.Glaciers in Chenab basin,as local freshwater resources,are very important to the regional ecological environment and development.At the same time,SBAS InSAR can monitor the deformation of the ground for a long time,the monitoring accuracy can reach mm level,and can obtain the time series change of deformation,whcih provides a new idea and method for glacier detection.In this study,the deformation from SBAS InSAR was combined with glacial area data to study the glacial changes in Chenab Basin.Sentinel-1 and Landsat series images were used to obtain the deformation and change in the area of glaciers by SBAS InSAR and the semi-automated method.The results showed that glaciers in the Chenab basin retreated rapidly,especially in the past ten years.The glacier area decreased by 88.05 km^(2)in 1990~2000 and 118.86 km^(2) in 2000~2010,and the glacier area decreased by 236.01 km^(2) in 2010~2020,which was the largest rate of change of 9.49%.Moreover,glacial deformation decreased in 2020,and the deformation rate ranged from-146.3mm/a to 119.52 mm/a.Most glaciers had deformation rates between-50 mm/a and 50 mm/a.Influenced by precipitation and temperature,glacial deformation in the Chenab basin started to change in August,the maximum accumulation was 6,828.43mm,and the minimum ablation was-20,656.41 mm.展开更多
The present investigation was conducted to analyze the temporal patterns of snow cover area%(SCA%), air temperature, snowfall and river discharge in parts of Chenab basin, western Himalayas. The relationship of mean S...The present investigation was conducted to analyze the temporal patterns of snow cover area%(SCA%), air temperature, snowfall and river discharge in parts of Chenab basin, western Himalayas. The relationship of mean SCA% with mean air temperature and river discharge was also tested using Pearson's product-moment correlation at 95% confidence limit and further sensitivity analysis of river discharge to SCA and SCA to air temperature was performed. Moderate Resolution Imaging Spectroradiometer(MODIS) 8-day surface reflectance product MOD09A1 was used to delineate SCA during the period 2000–2013. Moreover, variation in the lowest elevation from where snow cover area starts(LESCA) was also analyzed and its relationship with mean air temperature was also studied. Non-parametric method, Mann-Kendall test was employed to determine the trend in the SCA%, air temperature, snowfall and river discharge. The investigation carried out for three meteorological stations i.e. Batote, Reasi and Tandi revealed significant findings. At Batote and Reasi, statistically significant decreasing trends were observed over the period 2000 to 2012, for maximum, minimum and mean air temperature. Mean minimum SCA% exhibited a significant upward trend during 2000–2013 which is corroborated by the significantly increasing trend of mean annual snowfall(Tandi station) from 2000 to 2010. Further, significant decreasing trend of river discharge for the winter season at Batote station from 2000 to 2011 and decreasing trends in the maximum, minimum and mean air temperature at Batote and Reasi stations are also consistent with the increasing trend of SCA%. At both Batote and Reasi stations, mean SCA% exhibited significant negative relationship with the mean air temperature. On the other hand, LESCA exhibited positive correlation with the mean air temperature except in a few months, where negative relationship was seen. Sensitivity analysis of river discharge to SCA exhibited very low values of sensitivity coefficient in most of the months, indicating less sensitivity of river discharge to SCA. On the other hand, sensitivity coefficient of SCA to air temperature exhibited comparatively higher values which indicate SCA is more sensitive to air temperature.展开更多
Vulnerability assessment is essential for understanding and launching effective flood risk reduction strategies.This study aimed to examine the vulnerability of flood-prone rural communities in southern Punjab,Pakista...Vulnerability assessment is essential for understanding and launching effective flood risk reduction strategies.This study aimed to examine the vulnerability of flood-prone rural communities in southern Punjab,Pakistan to external shocks.The concept of vulnerability encompasses a range of dimensions,including physical,social,institutional,environmental,economic,and attitudinal.Using a composite index method,indices were developed for each dimension and combined to create a multidimensional measure of vulnerability.A sample of 365 communities was selected using the Yamane sampling technique,and data were collected through a questionnaire containing 65 indicators across all dimensions.Descriptive statistics and ANOVA tests were used to analyze the data.The results show that communities near the Chenab River had higher attitudinal and institutional vulnerability compared to other communities.High attitudinal vulnerabilities were as sociated with poorly perceived flood risks and low preparedness measures,whereas institutional vulnerabilities were driven by conventional flood protection strategies,lack of institutional trust,and lack of flood risk awareness.This research provides insights into the various components of vulnerability in flood-prone rural communities in Pakistan and demonstrates a useful methodology that can be applied to other disasters at different spatial scales.展开更多
基金funded by the National Natural Science Foundation of China(Grant Nos.41907396,42001388,42071277)Chongqing Research Program of Basic Research and Frontier Technology(No.cstc2019jcyj-msxmX0515)+3 种基金the Science and Technology Research Program of Chongqing Municipal Education Commission(Grant No.KJQN202200526)Preferential Funding Scheme for Ideological and Political Teachers and Counselors in Colleges and Universities(Grant No.FDYZY2020003)the Science Foundation of the Chongqing Normal University(22XLB002,22XLB003)Humanities and Social Sciences Research Program of Chongqing Education Commission(22SKSZ030)。
文摘The Chenab basin is located in northwest India and eastern Pakistan.Glaciers in Chenab basin,as local freshwater resources,are very important to the regional ecological environment and development.At the same time,SBAS InSAR can monitor the deformation of the ground for a long time,the monitoring accuracy can reach mm level,and can obtain the time series change of deformation,whcih provides a new idea and method for glacier detection.In this study,the deformation from SBAS InSAR was combined with glacial area data to study the glacial changes in Chenab Basin.Sentinel-1 and Landsat series images were used to obtain the deformation and change in the area of glaciers by SBAS InSAR and the semi-automated method.The results showed that glaciers in the Chenab basin retreated rapidly,especially in the past ten years.The glacier area decreased by 88.05 km^(2)in 1990~2000 and 118.86 km^(2) in 2000~2010,and the glacier area decreased by 236.01 km^(2) in 2010~2020,which was the largest rate of change of 9.49%.Moreover,glacial deformation decreased in 2020,and the deformation rate ranged from-146.3mm/a to 119.52 mm/a.Most glaciers had deformation rates between-50 mm/a and 50 mm/a.Influenced by precipitation and temperature,glacial deformation in the Chenab basin started to change in August,the maximum accumulation was 6,828.43mm,and the minimum ablation was-20,656.41 mm.
文摘The present investigation was conducted to analyze the temporal patterns of snow cover area%(SCA%), air temperature, snowfall and river discharge in parts of Chenab basin, western Himalayas. The relationship of mean SCA% with mean air temperature and river discharge was also tested using Pearson's product-moment correlation at 95% confidence limit and further sensitivity analysis of river discharge to SCA and SCA to air temperature was performed. Moderate Resolution Imaging Spectroradiometer(MODIS) 8-day surface reflectance product MOD09A1 was used to delineate SCA during the period 2000–2013. Moreover, variation in the lowest elevation from where snow cover area starts(LESCA) was also analyzed and its relationship with mean air temperature was also studied. Non-parametric method, Mann-Kendall test was employed to determine the trend in the SCA%, air temperature, snowfall and river discharge. The investigation carried out for three meteorological stations i.e. Batote, Reasi and Tandi revealed significant findings. At Batote and Reasi, statistically significant decreasing trends were observed over the period 2000 to 2012, for maximum, minimum and mean air temperature. Mean minimum SCA% exhibited a significant upward trend during 2000–2013 which is corroborated by the significantly increasing trend of mean annual snowfall(Tandi station) from 2000 to 2010. Further, significant decreasing trend of river discharge for the winter season at Batote station from 2000 to 2011 and decreasing trends in the maximum, minimum and mean air temperature at Batote and Reasi stations are also consistent with the increasing trend of SCA%. At both Batote and Reasi stations, mean SCA% exhibited significant negative relationship with the mean air temperature. On the other hand, LESCA exhibited positive correlation with the mean air temperature except in a few months, where negative relationship was seen. Sensitivity analysis of river discharge to SCA exhibited very low values of sensitivity coefficient in most of the months, indicating less sensitivity of river discharge to SCA. On the other hand, sensitivity coefficient of SCA to air temperature exhibited comparatively higher values which indicate SCA is more sensitive to air temperature.
文摘Vulnerability assessment is essential for understanding and launching effective flood risk reduction strategies.This study aimed to examine the vulnerability of flood-prone rural communities in southern Punjab,Pakistan to external shocks.The concept of vulnerability encompasses a range of dimensions,including physical,social,institutional,environmental,economic,and attitudinal.Using a composite index method,indices were developed for each dimension and combined to create a multidimensional measure of vulnerability.A sample of 365 communities was selected using the Yamane sampling technique,and data were collected through a questionnaire containing 65 indicators across all dimensions.Descriptive statistics and ANOVA tests were used to analyze the data.The results show that communities near the Chenab River had higher attitudinal and institutional vulnerability compared to other communities.High attitudinal vulnerabilities were as sociated with poorly perceived flood risks and low preparedness measures,whereas institutional vulnerabilities were driven by conventional flood protection strategies,lack of institutional trust,and lack of flood risk awareness.This research provides insights into the various components of vulnerability in flood-prone rural communities in Pakistan and demonstrates a useful methodology that can be applied to other disasters at different spatial scales.