Impact of Climate Change on Flood Frequency and Intensity in the Kabul River Basin

Abstract

Devastating floods adversely affect human life and infrastructure. Various regions of the Hindukush-Karakoram-Himalayas receive intense monsoon rainfall, which, together with snow and glacier melt, produce intense floods. The Kabul river basin originates from the Hindukush Mountains and is frequently hit by such floods. We analyses flood frequency and intensity in Kabul basin for a contemporary period and two future periods (i.e., 2031-2050 and 2081-2100) using the RCP4.5 and RCP8.5 scenarios based on four bias-corrected downscaled climate models (INM-CM4, IPSL-CM5A, EC-EARTH, and MIROC5). Future floods are modelled with the SWAT hydrological model. The model results suggest an increasing trend due to an increasing precipitation and higher temperatures (based on all climate models except INM-CM4), which accelerates snow and glacier-melt. All of the scenario results show that the current flow with a 1 in 50 year return period is likely to occur more frequently (i.e., 1 in every 9-10 years and 2-3 years, respectively) during the near and far future periods. Such increases in intensity and frequency are likely to adversely affect downstream population and infrastructures. This, therefore, urges for appropriate early precautionary mitigation measures. This study can assist water managers and policy makers in their preparation to adequately plan for and manage flood protection. Its findings are also relevant for other basins in the Hindukush-Karakoram-Himalayas region.

Modeling Escherichia coli fate and transport in the Kabul River Basin using SWAT

“…However, Figure 3 shows that the model slightly overestimates low concentrations and underestimates high concentrations. The lower estimates of peak concentrations are directly related to the too low estimate of peak discharge, as explained in (Iqbal et al 2018). Such low estimate is standard in hydrological modeling (D€ oll et al 2003).…”

“…The model structure was built with the help of ArcGIS software, which provides graphical information of the watershed and allows for the definition of watershed hydrology. The SWAT model was calibrated for daily discharge for 2007-2011 and validated for 2012-2015, respectively (Iqbal et al 2018). The model evaluation statistics or skill score showed good agreement between measured and simulated results.…”

“…The coefficient of determination (R 2 ) was 0.84 and 0.77, Nash-Sutcliffe Efficiency Index (NSE) outcome was 0.77 and 0.72 and percent bias (PBIAS) values were 22.2 and 17.7 for calibration and validation time periods, respectively. Based on the model efficiency (Moriasi et al 2007), overall the model describes the hydrological process of the watershed systems as good (Iqbal et al 2018). The model calibrated at a daily time step has been used at the monthly resolution here.…”

Multi‐criteria decision analysis for flood risk on the Chenab River

“…Flooding is one of the most common types of disaster worldwide (Saudi et al , ). Globally, human life and important societal infrastructure are seriously affected by devastating flood events (Kia et al , ; Iqbal et al , ). At various locations across the world, the magnitude and frequency of flood events are increasing.…”

“…During the first half of the twentieth century, the main reason for high river flow was the fact that snow was melting more quickly due to increases in temperature (Ali et al , ). According to various climatic models, except INM‐CM4, increasing precipitation and higher temperature are accelerating the melting of both snow and glaciers (Iqbal et al , ).…”