Projections of the impacts of climate change on the water deficit and on the precipitation erosive indexes in Mantaro River Basin, Peru

• Published in: Journal of mountain science Vol. 15; no. 2; pp. 264 - 279
• Main Authors: Wongchuig, Sly C., Mello, Carlos R., Chou, Sin C.
• Format: Journal Article
• Language: English
• Published: Heidelberg Science Press 01.02.2018; Springer Nature B.V
• Subjects: Agriculture; Atmospheric precipitations; Climate change; Climate models; Computer simulation; Development projects; Earth and Environmental Science; Earth Sciences; Ecology; Electric power generation; Environment; Environmental impact; Evaporation; Evaporation rate; Farm buildings; Geography; Global climate; Greenhouse effect; Greenhouse gases; Intergovernmental Panel on Climate Change; Precipitation; Rain; Rainy season; River basins; River valleys; Rivers; Slope; Slopes; Statistical analysis; Statistical significance; Sustainable development; Temporal distribution; Tropical climate; Water deficit; Water supply; Wet season; Peru; Modified Fournier Index (MFI); Climate change; Precipitation; Evaporation; Precipitation Concentration Index (PCI); Tropical Andes
• ISSN: 1672-6316; 1993-0321; 1008-2786
• DOI: 10.1007/s11629-017-4418-8

Projections of climate change are essential to guide sustainable development plans in the tropical Andean countries such as Peru. This study assessed the projections of precipitation and potential evaporation, rain erosive potential, and precipitation concentration in the Mantaro River Basin, in the Peruvian Andes, which is important for agriculture and energy production in Peru. We assumed the Intergovernmental Panel on Climate Change (IPCC) A1B greenhouse gas emission scenario and simulated the global climate change by the HadCM3 global climate model. Due to the steepness of the mountain slopes and the narrowness of the river valley, this study uses the downscaling of the global model simulations by the regional Eta model down to 20-km resolution. The downscaling projections show decrease in the monthly precipitation with respect to the baseline period, especially during the rainy season, between February and April, until the end of the 21st century. Meanwhile, a progressive increase in the monthly evaporation from the baseline period is projected. The Modified Fournier Index (MFI) shows a statistically significant downward trend in the Mantaro River Basin, which suggests a possible reduction in the rain erosive potential. The Precipitation Concentration Index (PCI) shows a statistically significant increasing trend, which indicates increasingly more irregular temporal distribution of precipitation towards the end of the century. The results of this study allow us to conclude that there should be a gradual increase in water deficit and precipitation concentration. Both changes can be negative for agriculture, power generation, and water supply in the Mantaro River Basin in Peru.