Caracterización del comportamiento futuro de la precipitación asociado al fenómeno de cambio climático en el área de producción hidroeléctrica embalse Arenal, Costa Rica

Abstract

Identifying and understanding the effects of climate change is critical to
formulating optimal adaptation and mitigation measures. One of the priority
issues for socioeconomic development is energy stability; however, some
sources, such as hydroelectricity, are vulnerable to this phenomenon. Therefore,
the main objective of the research is to identify the climatic variations that
climate change could generate, with special emphasis on precipitation, in the
hydroelectric production area of Arenal reservoir, Costa Rica.
The materials used include historical records of meteorological stations
with a base period from 1971 to 2000, as well as modeled and downscaled
series from the MRI-CGCM3 model, for the Central American zone, in two
scenarios of increasing radiative forcing (RCP 4.5 and RCP 8.5) with future
horizon to 2100.
Climatic variability was established by the calculation of climatic indices
defined by the ETCCDI: simple precipitation intensity index, annual count
of days when PRCP ≥ 1 mm, maximum duration of the dry spell, maximum
duration of the period of rainfall and total annual precipitation on wet days.
The main findings of the research show evidence of alterations in the
intensity and frequency of precipitation in the study area, mainly associated
with decreases of medium magnitude in the amount of annual precipitation
and the count of wet days, while there would be increases in the maximum
length of dry spell, which is an unfavorable scenario for hydroelectric
production and for other economic activities. In general, the indices that
present significant variations are characterized by effects of medium
magnitude compared to historical data, although indices such as PRCPTOT,
SDII and CDD would present changes with a large effect, mainly between the
medium and distant future, with the Tilarán area being the most affected,
compared to the area of La Fortuna.