From 1990 to 2010, Southeast Asia was the fastest growing carbon emitter in the world, according to the Asia Development Bank. Although its historical share of global greenhouse gas emissions – primarily carbon dioxide, water vapor, methane, and nitrous oxide – is not as large, the region is on a trajectory that will make it a significant emitter in the future.
Nonetheless, the impacts of climate change in the region are already evident. One of the most impacted countries is Thailand. From 1997 to 2016, Thailand was ranked in the top 10 countries at long-term risk of climate change according to a 2018 report by Germanwatch – a non-profit think-tank in Bonn, Germany. According to Germanwatch, Thailand lost an average of 140 people and $7.6bn each year to climate events during this period.
One of the most damaging of these climate events in Thailand is flooding, and it is not the only country affected, as the US experienced late last year through Hurricane Harvey in Texas, where 88 people died.
How is climate change increasing floods?
The natural warming of the earth, that regulates our planet’s climate, occurs when energy from sunlight enters the earth’s atmosphere. Energy from this sunlight is absorbed by the earth, and some is reflected back as heat energy into the atmosphere. Of the heat energy reflected back, a portion is trapped in the atmosphere absorbed by greenhouse gases, warming the earth, and some escape among the gases back out into space.
A higher concentration of greenhouse gases in the atmosphere increases the amount of heat trapped from the sun, as more of the reflected heat energy from the earth is absorbed by more greenhouse gases. The additional heating of the earth in this way is the main cause of global warming, and increasing floods.
93% of the extra heat trapped by manmade global warming pollution goes into the oceans, which make up 71% of the earth’s surface. The additional heat increases:
the melting of the polar ice caps releasing more water into the oceans;
the warming of oceans expanding the volume these vast bodies of water occupy; and
the rates of water evaporation generating heavier and longer downpours of rain.
Since 1993 to 2017, global warming has contributed to an average sea level rise of 3.3 inches (84.8 mm), which is still rising at a rate of 0.13 inches (3.20 mm) every year, according to NASA.
Graph of Sea Height Variation vs. Time
Sea level rise and increased rain have posed serious flood risks for Bangkok, the capital city of Thailand, which is already close to sea level. To make things worse, rapid urban infrastructure developments and excessive pumping of groundwater have caused Bangkok to sink into its upper clay level. A lack of green space and drainage built into urban developments have meant that seasonal monsoon rains have no place to go, but to flood streets and houses. But, architecture may have an answer.