As humans continue to emit greenhouse gases into the atmosphere, the planet’s oceans have changed due to it. The seas have absorbed more than 90% of the heat from the harmful gases. Scientists constantly express their concerns regarding climate change, describing the complex shifts now affecting our planet’s weather and climate systems. Rising sea levels are one of those climate change effects. Average sea levels have risen over 23 cm since 1880, with every year, the sea level rising 3.2 mm in height.
The change in sea levels is linked to three primary factors:
- Thermal expansion:
When water heats up, it expands. About half of the sea-level rise over the past 25 years is attributable to warmer oceans occupying more space.
- Melting glaciers:
Large ice formations such as mountain glaciers naturally melt to an extent each summer. This is followed by heavy snow and thick icebergs in the winters, thus maintaining balance in the environment. But since the last few decades, due to climate change, the natural summer ice melting lasts longer than usual. The atmosphere is so hot that even in the winter the cold isn’t able to re-freeze all the melted ice, thus, causing sea levels to rise.
- Loss of Greenland and Antarctica’s ice sheets:
Due to large amounts of heat accumulating on either side of the planet, the land on and around the poles, Greenland and Antarctica, are losing massive ice sheets making it melt more quickly. Scientists also believe that melted water from above and seawater from below is seeping beneath Greenland’s ice sheets, lubricating ice streams and causing them to move more quickly into the sea.
Even a small increase in sea level, have devastating effects on coastal habitats, it can cause destructive erosion, wetland flooding, aquifer and agricultural soil contamination with salt, and destruction of habitat for fish, birds, and plants. Higher sea levels along with dangerous hurricanes and typhoons move more slowly resulting in heavy rain, contributing to more powerful storm surges that can strip away everything in their path. Already, flooding in low-lying coastal areas is forcing people to migrate to higher ground, and millions more are vulnerable from flood risk and other climate change effects. The prospect of higher coastal water levels threatens basic services such as Internet access, since much of the underlying communications infrastructure lies in the path of rising seas.
While all coastal cities will be affected by sea-level rises, some will be hit much harder than others. About four out of every five people impacted by sea-level rise by 2050 will live in East or South-East Asia. US cities, especially those on the East and Gulf coasts, are similarly vulnerable. More than 90 US coastal cities are already experiencing chronic flooding every year and that number is expected to double by 2030. About 3 in every 4 European cities, will be hit hard by massive flooding. Africa is also highly threatened, due to rapid urbanization in coastal cities and the crowding of poor populations in informal settlements along the coast. Big cities like New York, Mumbai, Tokyo, Shanghai, to name a few, are all predicted to go under water in just a few decades if no action is taken. Only a few nations, like Singapore, Finland, New Zealand, Austria, are taking this dangerous situation seriously and spending billions of dollars to build infrastructure to protect itself from potential destruction in the future.