Land-use change may exacerbate climate change impacts on water resources in the Ganges basin
Land-use change may exacerbate climate change impacts on water resources in the Ganges basin
复制标题
土地利用变化可能加剧气候变化对恒河流域水资源的影响
DOI：
10.5194/hess-22-1411-2018
复制
发表时间：
2017-08
影响因子：
6.3
通讯作者：
G. Tsarouchi;W. Buytaert
中科院分区：
文献类型：
--
作者：
G. Tsarouchi;W. Buytaert
抽象的。量化土地利用变化和气候变化如何影响水资源是水文科学的一项挑战。这项工作的目的是量化土地利用和气候变化的未来预测可能会影响上游恒河流域的水文响应在北方印度，经历季风洪水几乎每年。使用联合王国陆地环境模拟器（JULES）陆面模型（LSM）进行了三组不同的模拟实验，涵盖2000-2035年：在第一组中，只考虑了气候变化，JULES由CMIP驱动5（耦合模型相互比较项目第5阶段）21个模型在两个代表性浓度路径下的输出（RCP4.5和RCP8.5），而土地使用在2010年固定不变。在第二组中，只考虑土地利用变化，JULES是由15个未来土地利用路径的时间序列驱动的，基于Landsat卫星图像和马尔可夫链模拟，而气象边界条件固定在2000-2005年。在第三组中，考虑了气候变化和土地利用变化，因为CMIP 5模型的输出与15个未来土地利用路径结合使用，以迫使JULES。在模拟期间计算水文变量（径流，蒸散和土壤湿度）的变化。在未来土地覆盖和气候变化情景下，近期（2030-2035年）水文通量将发生重大变化，表明极端流量将大幅增加：在土地利用和气候变化高排放情景下，预计径流量第95百分位数（Q5）的多模型平均值将增加63%（RCP 8.5）。在土地使用和气候变化综合试验中，所有被检查的水文组成部分的变化都更大。结果进一步介绍了水资源的背景下，旨在解决气候变化和土地利用变化的潜在影响，从水需求的角度来看。我们的结论是，恒河上游地区未来冬季的用水需求可能无法得到满足。
Abstract. Quantifying how land-use change and climate change affect water resources is a challenge in hydrological science. This work aims to quantify how future projections of land-use and climate change might affect the hydrological response of the Upper Ganges river basin in northern India, which experiences monsoon flooding almost every year. Three different sets of modelling experiments were run using the Joint UK Land Environment Simulator (JULES) land surface model (LSM) and covering the period 2000–2035: in the first set, only climate change is taken into account, and JULES was driven by the CMIP5 (Coupled Model Intercomparison Project Phase 5) outputs of 21 models, under two representative concentration pathways (RCP4.5 and RCP8.5), whilst land use was held fixed at the year 2010. In the second set, only land-use change is taken into account, and JULES was driven by a time series of 15 future land-use pathways, based on Landsat satellite imagery and the Markov chain simulation, whilst the meteorological boundary conditions were held fixed at years 2000–2005. In the third set, both climate change and land-use change were taken into consideration, as the CMIP5 model outputs were used in conjunction with the 15 future land-use pathways to force JULES. Variations in hydrological variables (stream flow, evapotranspiration and soil moisture) are calculated during the simulation period. Significant changes in the near-future (years 2030–2035) hydrologic fluxes arise under future land-cover and climate change scenarios pointing towards a severe increase in high extremes of flow: the multi-model mean of the 95th percentile of streamflow ( Q5 ) is projected to increase by 63 % under the combined land-use and climate change high emissions scenario (RCP8.5). The changes in all examined hydrological components are greater in the combined land-use and climate change experiment. Results are further presented in a water resources context, aiming to address potential implications of climate change and land-use change from a water demand perspective. We conclude that future water demands in the Upper Ganges region for winter months may not be met.