Late last night, the Intergovernmental Panel on Climate Change (IPCC) released a special report on the social and economic consequences of 1.5 degrees Celsius (2.7 degrees F) of warming compared to 2 degrees Celsius (3.6 degrees F).
Changing the temperature in your home by one or two degrees may not seem like a big deal, but when temperatures change across the globe by that much, major cities across the world will be threatened by sea level rise, and millions of people will have to be uprooted from their homes.
Rising seas are already affecting coastal communities and small island nations, and the report found that 1.5 degrees C of warming could mean about 0.26 meters (0.85 feet) to 0.77 meters (2.5 feet) of sea level rise by 2100. For 2 degrees C, average sea levels could rise an additional 0.1 meters.
The difference between 1.5 and 2 degrees C may seem minor, but the 0.1 meter difference could expose 10 million more people to flooded homes, according to the report. Every tenth of a degree means more people evacuating to find another place to live.
Experts at the IPCC also warned that if ice sheets in Antarctica and Greenland break up and melt, multiple meters of several rise could be seen in the long term.
The higher the temperature climbs the more costly and dangerous the impacts. If we don’t take action to reduce emissions, global warming could reach 2.7 to 3.7 degrees C by 2100, which could result in significant damage to low-lying areas and more than a meter of sea level rise.
Climate scientists recently released a study indicating that if emissions aren’t reduced, sea levels may rise up to 1.5 meters (5 feet) by 2100. This much sea level rise could submerge land currently home to more than 153 million people. The study, led by Dr. Robert Kopp of Rutgers University and co-authored by scientists at Climate Central, looked at how the break-up of Antarctic ice sheets could cause sea level to rise even faster than previous estimates.
Using Climate Central data hosted on Resource Watch, we can explore areas likely to be flooded by 0.5 and 1.5 meters of sea level rise. Many major cities are at risk from climate change and sea level rise, but five major ones are highlighted below.
The rapidly growing port city of Guangzhou in China has a population of 14 million and, according to a 2013 World Bank report, has the most to lose economically from climate change.
Climate Central researchers estimate that due to sinking land and ice mass loss from Antarctica, Gulf and East Coast states in the United States are especially vulnerable to sea level rise. New Orleans and New York City are shown below.
About 12 million people live in the coastal mega-city of Mumbai, making it the most populated city in India. Dubbed the “financial heart of India,” the city houses important financial institutions such as the National Stock Exchange of Mumbai.
Osaka is a major port and commercial hub in Japan. The city’s off-shore airport, Kansai International Airport, is near sea level and was flooded in September after a typhoon.
Seas will most certainly rise by the end of the century, threatening major cities and the livelihoods of millions of people, but the extent of rise depends on governments stepping up to set goals and policies that limit warming.
It’s clear from these maps that every foot of sea level rise matters. The next few years are crucial for avoiding catastrophic sea level rise. The good news is, we have the tools we need to make far-reaching changes to how we power our homes and businesses, grow our food and design our cities.
Make your own maps of sea level rise on Resource Watch and create data visualizations like the map below.