Climate change in East Asia is expected to cause rising sea levels, more severe storms that will increase flooding and more intense droughts, putting some 12 million people from 23 cities at risk and costing as much as $864 billion USD, according to a new report from the Asian Development Bank.
The report, “Economics of Climate Change in East Asia,” found that while the cost of losses from climate change may be significant, the cost of protection against climate change can be much smaller.
“The aggregate cost to protect the most vulnerable sectors — infrastructure, coastal protection, and agriculture — would be less than 0.3 percent of East Asia’s gross domestic product (GDP) every year between 2010 and 2050,” it found.
“Since 1970, economic losses to the four countries from climate-related natural disasters have amounted to more than $340 billion,” the ADB added.
The report recommended that China, Japan, Korea and Mongolia work together to invest in climate change adaptation.
“… The cost of inaction far outweighs the cost of climate change adaptation if countries act now. Climate change not only brings challenges to East Asia, but also opportunities for stronger regional cooperation,” said Ayumi Konishi, Director General of ADB’s East Asia Department.
China is particularly vulnerable. More than 1 million people along China’s coastal areas could be displaced due to sea level rise and flooding by 2050, if the country does not take action. This displacement could cost the country $153 billion USD.
However, the report estimated that the cost to climate-proof all of China’s infrastructure, including drainage and roads, would be some $44 billion USD each year from 2010 to 2050.
“Protection of [China’s] coastal areas by building dikes and upgrading port facilities makes economic sense. The costs of preparing for, and protection against, climate-related events are much lower than the damage that would be caused without adaptation efforts,” said Jörn Brömmelhörster, principal economist in ADB’s East Asia Department and one of the report’s main authors.
The report predicted that extreme once-in-20-years flooding will occur every four years by 2050 in coastal China. Coupling this with sea level rise, an estimated 102 square kilometers of land could be lost each year, amounting to an area of 4,000 kilometers — a land mass approximately four times that of Hong Kong — by 2050. The country’s most vulnerable cities are the international ports of Shanghai and Tianjin, and the most vulnerable economic centers are in Guangdong and Jiangsu provinces.
The report said Mongolia will need to spend up to $560 million USD per year between 2010 and 2050 to protect its infrastructure from severe weather conditions.
Agriculture is that country’s most vulnerable sector. “If climate change causes more variable weather, the frequency of dzuds (extreme cold and heavy snow) may increase even if the average temperature goes up. Hotter weather and greater seasonal rainfall could exacerbate the degradation of pasture land, hurting farmers across Mongolia,” Brömmelhörster said.
The scenario for Japan and South Korea is somewhat different. The report noted that in these countries the cost of full adaptation to climate change could exceed expected losses, so “a strategy of partial rather than full adaptation may be more efficient.”
Increases in temperature and precipitation are projected to increase total crop production in the two countries, even as they lead to a decrease in crop production in China. And they are at less risk of flooding than China.
However, Japan and Korea are at high risk from tropical cyclones. The report said each of the 10 costliest typhoons in the North Pacific between 1980 and 2012 affected one of these countries.
While “the increase in economic losses due to cyclones may be significant in Japan and the Republic of Korea, the costs of adaptation are modest,” it added.
Areas of Japan are also vulnerable to sea level rise. The report found that rising sea levels could displace some 64,000 people in Japan and cost the country $7.8 billion USD. Some 4,000 people in South Korea could be displaced by rising sea levels.
Japan could lose about 28 percent of its coastal wetlands by 2050, and South Korea could lose 22 percent, it said.