IMPACT OF CLIMATE CHANGE ON INTENSITY-DURATION-FREQUENCY CURVES IN HO CHI MINH CITY

Tóm tắt

Viet Nam is considered as one of the countries most affected by climate change. The magnitude and frequency of extreme events (such as high-intensity rainfall, flooding, severe droughts) are expected to increase in future due to climate change. The evaluation of the possible climate change influence on extreme precipitation is very interesting in megacities city due to the usual and characteristic high intensities of its rainfall pattern. This study aims at developing Intensity-Duration-Frequency (IDF) curves for Ho Chi Minh City, Viet Nam for the present as well as future climatic scenarios. The rainfall projections for future periods based on ensemble regional climate modeling approach are used to calculate IDF curves and their plausible changes in the middle of the 21^st century (2050s), and at the end of 21^st century (2090s). The results suggest that intensities of extreme rainfall events versus various durations with different return periods are all likely to increase over time in comparison with baseline period (1986-2005): [11, 60]% in 2050s, and [15, 69]% in 2090s under most likely case; and [38, 141]% in 2050s, and [28, 105]% in 2090s under high impact case. Such a consistent increase in the exceedance values of rainfall intensity of extreme events, implying that intense rainfall events are likely to occur more frequently in the future under climate change. The results presented in this paper are important for the design and construction of different hydrological structures in water management in Ho Chi Minh City.