EGU22-7263, updated on 28 Mar 2022
https://doi.org/10.5194/egusphere-egu22-7263
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Hydrological Impact Assessment of Climate Change on a Tropical River Basin in Southern India

Swatantra Kumar Sharma, Rakesh Kumar Sinha, and Eldho T. I.
Swatantra Kumar Sharma et al.
  • Department of Civil Engineering, Indian Institute of Technology Bombay, Mumbai, India (er.swatantra@gmail.com)

The climate change has a significant contribution in the uncertainty in the river flow. In this study, the uncertainty in the river flow of Pamba River Basin (PRB) in South India is investigated due to climate change impacts. In order to assess the hydrological impact in the basin for future preparedness and planning for sustainable use of water resources, an ensemble of five general circulation models (GCMs) and hydrological model SWAT (soil and Water Assessment Tool) were used. The objective of the present study was to understand the surface runoff change over the PRB in the near future (2016-2030) under representative concentration pathways (RCP) 4.5 and 8.5 of the downscaled ensemble GCM data. Furthermore, spatial runoff change at sub-basin scale and percentage runoff change at monthly scale in the PRB were assessed. Hence, to study the impact due to climate change, SWAT model was simulated with base period historical data (1984 – 2015) and future climate data (2016 – 2030), and then changes at spatial and monthly scale were plotted. The results shows that at basin scale, there is an overall increase in the mean runoff by the 1.4 % and 3.0% under RCP4.5 and RCP 8.5 scenarios respectively. At seasonal scale, winter shows a tremendous increase in the runoff with around 38% increase in both RCP 4.5 and RCP 8.5, followed by summer with 17.9% and 18.6% for RCP 4.5 and RCP 8.5 scenarios respectively. Notably, Monsoon witnesses a negative trend in both the scenarios with -18.6% and -15.5% runoff change from the base period. This study will be useful in future water resources management in the basin at micro-level due the spatial and temporal variations.

Keywords: Climate change; SWAT model; GCMs; runoff change; spatial, and temporal change.

How to cite: Sharma, S. K., Sinha, R. K., and T. I., E.: Hydrological Impact Assessment of Climate Change on a Tropical River Basin in Southern India, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-7263, https://doi.org/10.5194/egusphere-egu22-7263, 2022.

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