A decline in water flows from Himalayan glaciers due to climate change would trigger a ''cascade of economic, social and political consequences," warned Heather Smith, deputy director of Australia's Office of National Assessments, the country's top intelligence agency.
Smith's assessment was part of a confidential conversation on the national security implications of climate change with U.S. Embassy officials, The Sydney Morning Herald reported Thursday.
''Southeast Asia because of political turmoil, a growing youth demographic and a general increase in population [will be] worst affected,'' a U.S. government cable reporting the briefing noted. The Herald said the cable was obtained by WikiLeaks and released to the newspaper.
''Southeast Asia faces wild monsoons variations, with effects on littoral infrastructure, agriculture, marine currents and fish stocks. Coastal cities to be hit by subsidence and rising sea levels," the cable said.
The cable also reveals that Canberra chose to encourage Pacific nations faced with the threat of rising sea levels to make incremental decisions, even though their populations might be eventually forced to evacuate.
''[Foreign Affairs] Secretary [Michael] L'Estrange said Australia planned to raise the issue at the Pacific Islands Forum meeting … and would urge the Pacific island nations to address environmental problems incrementally rather than focusing on worst-case scenarios immediately,'' the cable said.
In June, a U.N. scientist warned that Australia could face a wave of climate refugees from neighboring Pacific islands unless rich nations help poorer countries with climate change.
The ONA's assessment in the cable says that China could potentially be the biggest loser due to decreased river flows, which could lead to international confrontations with states sharing the Mekong system.
The Mekong River is the longest river in Southeast Asia.
Expected food shortages could force ''China to trade for the first time in new agricultural markets," ONA said in the cable.
The Asian Development Bank, during the climate change conference in Cancun, Mexico, said climate change poses an economic and environmental threat to countries in the Asia and Pacific region, in which more than half of the world's poor live.
David McCauley, ADB's chief climate change specialist, told China's state-run news agency Xinhua in Cancun that "enhanced cooperation" through regional and sub-regional bodies such as the South Asian Association for Regional Cooperation and the Association of Southeast Asian Nations is "vital" to address climate change.
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