Future economic impacts of climate change in the Lower Mekong Basin, including Vietnam, are likely to be wide-ranging and could top US$34 billion annually, according to a report recently released by the U.S. Agency for International Development (USAID).

The biggest concerns as mentioned in the report are potentially sharp reductions in the yield of crops, fish and non-timber forest products critical for livelihoods, damage to infrastructure associated with floods and sea level rises, and an increase in the incidence and severity of heat-related illnesses for workers.

The report “Climate Change in the Lower Mekong Basin: An Analysis of Economic Values at Risk” estimates that, based on current values, impacts from climate change could cost Cambodia, Laos, Thailand and Vietnam at least US$16 billion per year in damage to natural resource assets and infrastructure services, and an additional US$18 billion annually in potential infrastructure damage or loss from flooding and other extreme weather events.

This amount shows the profound risk that climate change represents and points to a need to align national adaptation strategies to reduce this risk where possible.

Authored by the Washington, D.C.-based think tank World Resources Institute (WRI) for the USAID Mekong Adaptation and Resilience to Climate Change (USAID Mekong ARCC) project, the report is based on a 2013 USAID analysis of climate change impacts in the Lower Mekong Basin that forecasts more extreme temperatures, rainfalls, weather events and sea level rises for the region by 2050.

“We hope this work will help equip policymakers with the kind of information and analysis that can better prioritize investments in climate change adaptation and spur follow-on valuation studies in the region,” said USAID Regional Development Mission for Asia Director Michael Yates.

The report also points out that the single highest value asset at risk from climate change in the region is worker productivity with more than US$8 billion at risk per year in lost work days due to heat-induced illness.

High temperatures, which already affect open-air workers such as farmers and construction workers, will likely increase as a result of climate change, causing spikes in cases of heat stress and other heat-related illnesses in dry season.

“So much of the Lower Mekong Basin’s economy is based on outdoor labor,” says report author John Talberth. “Worker productivity should be front and center for any adaptation plans and fast-tracked.”

Built infrastructure services (US$3.4 billion), crop production (US$2.54 billion), ecosystem services (US$1.24 billion) and hydroelectric power (US$430 million) are also at risk from climate change.

Despite the challenge posed by climate change, Talberth is certain that positive steps can be taken to address potential economic and environmental losses.

“If we address the problem early enough - and it is still early enough - we can make investments that are likely to pay off many times over,” Talberth said.