The extreme climate event change trend forecast in the Huaihe River Basin, China

ABSTRACT First, this paper studied the selection of indices for extreme climate event evaluation. Then, the estimation of the extreme value distribution of rainfall events in different recurrence periods was studied. A reversible jump Markov chain Monte Carlo method based on a generalized extreme distribution was proposed. For data series analysis in different scenarios, the method of equal weight set average was adopted. Finally, based on three climate models, the spatio-temporal variation characteristics of the extreme climate in the Huaihe River Basin under three scenarios (RCP 2.6, RCP 4.5, and RCP 8.5) were forecasted. The spatial distribution of the daily maximum and minimum temperatures shows a consistent trend, increasing from the upper reaches to the middle and lower reaches of the Huaihe River. Extreme rainfall analysis in different recurrence periods under the three scenarios revealed that the maximum 1-day and 5-day rainfall amounts were greater than those in the historical periods in the Huaihe River Basin. The annual precipitation in the Huaihe River Basin shows a weak increasing trend. It can be shown from the study results that by the late 21st century, climate change under the future climate change impact scenarios will increase greatly.