Thread by @MekongMonitor

The S Asian monsoon typically drives summer rains in S Asia, SW China, & mainland SE Asia. This year, an unusual monsoon pattern is driving severe droughts in the upper Ganges, upper Mekong, & throughout the Yangtze, affecting livelihoods of hundreds of millions of people. 1/9

Instead of originating in the Bay of Bengal, this year’s monsoon began in the Arabian Sea & moved north. This drives aforementioned drought & extreme flooding in Pakistan, which displaced over 33 million & killed over 1000 people in the worst flash flooding event in memory. 2/9

The Mekong is getting closer to the time when the wet season flood pulse peaks & then begins to recede. The flood pulse continues to be well below normal as a result of lower-than-normal rainfall throughout the basin and upstream dam restrictions. 3/9

The map's light green areas show what parts of the lower Mekong should be underwater at this time of year. This year’s flood pulse is wetter & wider than the previous two, but it's not enough to support a high fish catch & normal agricultural yields in Cambodia & Vietnam. 4/9

Over the last 10 weeks, water held in major #Mekong reservoirs rose from 27% to ~50% of what those reservoirs can collectively hold. The amount will continue to rise as wet season flows are restricted despite impacts to the Tonle Sap fishery & Vietnam’s agricultural harvests. 5/9

Last week, dams in the lower basin restricted about 2 billion cubic meters of water. Due to drought conditions, total restrictions in China were much lower than usual at this time of year at just over 200 million cubic meters.

Learn more at monitor.mekongwater.org. 6/9

River Levels: Upstream dam restrictions are showing up at Chiang Saen, Thailand, where @EyesOnEarth2 estimates 28% of water is missing. The river level at Stung Treng, Cambodia is about one meter below average level. 7/9

Wetness & Weather: Temperatures in the Mekong headwaters in China were extremely high last week, reaching as much as 9 degrees higher than normal in some places, worsening drought and melting the glaciers. 8/9

Excess wetness remains around the Golden Triangle and also in the 3S Basin. Temperatures in the lower basin are slightly above average temperatures.

Learn more at monitor.mekongwater.org. 9/9