Projection of the impacts of climate change on the flow of the Lurín river basin-Peru, under CMIP5-RCP scenarios

Díaz K.J.O.; Fernández L.R.; Bejarano T.V. · Idesia (2022) · DOI: 10.4067/s0718-34292022000100101

Resumen

The impact of climate change at the end of the 21st century was evaluated in the Lurín river basin, a representative coastal basin of the Pacific Ocean slope in Peru, with a seasonal precipitation regime influenced by the Andes mountain range. The statistical downscaling of precipitation and temperature projections of six global climate models (GCM) of the CMIP5, under three representative concentration pathways of greenhouse gas emissions increasing intensities (RCP 2.6, 4.5 and 8.5) were entered into a distributed hydrological model, together with geographic information of the study area. The correction of the error by statistical downscaling was carried out by delta change, distribution mapping and scaling; which were compared with the reference period (1950-2018). By the end of the 21st century, it is expected in the upper zone that precipitation will decrease; meanwhile, in the middle and lower zones, it will increase, reaching values of 95 to 221 mm in the lower zone compared to the 17 mm of reference precipitation; moreover, an increasing temperature and various variations in evapotranspiration are expected throughout the basin. In the projected annual flow in the upper zone, a decrease of 36% to 50% is expected and in the middle zone, an increase of 14% to 44%; whereas, in the low zone, both trends are expected, possibly influenced by the uncertainty dependent on the reduction of scale and resolution of the GCM. These results will make it possible to formulate development and adaptation strategies that include water and irrigation regulation; and thus, have adequate and timely availability of water resources for optimal human development in the future.

Instituciones: Universidad Nacional Agraria La Molina