A landslide along a riverbank in the Mekong Delta Dong Thap Province's Hong Ngu District. A new research study shows that climate and flood variability has been increasing in recent decades in the Mekong River Basin. — VNA/VNS Photo Van Tri
HCM CITY (VNS)— The Mekong River Basin has experienced increased climate and flood variability in recent decades, according to a new research report from a doctoral student at Finland’s Aalto University.
Timo Rasanen told Viet Nam News that “solid research evidence” showed varying weather patterns that could become more intense in coming years.
His findings were published in the report “A Palaeo-Climatological Perspective on River Basin Hydro-Meteorology: The Case of the Mekong”.
According to Rasanen, water-resources development in the basin, together with climate variability and change, will have a cumulative impact on Mekong River flows, and, in turn, may result in “unexpected consequences”.
He pointed out, however, that stable long-term climate conditions do not exist, and that weather patterns and the flow of the Mekong River have varied normally between drier and wetter periods in multi-annual and decade-long periods.
But in recent decades, there has been a significant increase in inter-annual climate and flood variability, and a higher likelihood of extreme floods, he said.
In addition, these levels of inter-annual variability have not been experienced in the past 700 years.
The climate variability in the Mekong region in recent decades has been due to ocean-atmosphere phenomena such as El Nino-Southern Oscillation, which has become more variable in recent decades.
Other climate factors may have also contributed to the increased climate and flood variability, he said.
“The future is uncertain,” Rasanen said.
Temperatures and rainfall are likely to rise in the Mekong region, but to what extent it is uncertain, as the estimates vary between the climate models.
In addition, he said other research has found that the Mekong Basin is experiencing extensive hydropower development, which will affect its flood regime by increasing dry season flows and decreasing wet season flows.
The findings on increased climate and flood variability are based time-series analysis of measured discharge of the Mekong and tree ring record based palaeo-climate proxy.
Rasanen has been visiting Mekong region countries like Viet Nam, Laos, Cambodia and China regularly since 2009 during which he spent between two and four months every year in the region for the research.
The research has been published on international scientific peer review journals like Journal of Hydrology and Hydrology and Earth System Sciences. — VNS
Đăng ký: VietNam News