Global models of tide, storm surge, and wave setup are used to obtain projections of episodic coastal flooding over the coming century. Recently, a study in journal Scientific reports made predictions that a large population and assets will be globally affected as a consequence of Sea Level Rise (SLR).
Daily Current Affairs Quiz 2020
Key-Points
SLR is a consequence of climate change, which is predicted to increase coastal flooding by 2100. The global population potentially exposed to episodic coastal flooding will increase from 128-171 million to 176-287 million by 2100. 0.5-0.7% of the world’s land area is at a risk of episodic coastal flooding by 2100, impacting 2.5-4.1% of the population.
The value of global assets exposed to coastal flooding is projected to be between 6,000-$9,000 billion USD, or 12-20% of the global GDP.
Globally, of the 68% area that is prone to coastal flooding, over 32% can be attributed to regional SLR.
For most of the world, flooding incidents that are typically associated with a 1 in a 100-year event could occur as frequently as 1 in 10 years, primarily as a result of SLR.
When water heats up, it expands. About half of the sea-level rise over the past 25 years is attributable to warmer oceans simply occupying more space.
Higher temperatures caused by global warming have led to greater-than-average summer melting of large ice formations like mountain glaciers as well as diminished snowfall due to later winters and earlier springs. That creates an imbalance between runoff and ocean evaporation, causing sea levels to rise.
As with mountain glaciers, increased heat is causing the massive ice sheets that cover Greenland and Antarctica to melt more quickly, and also move more quickly into the sea.
Global sea level has been rising over the past century, and the rate has accelerated in recent decades. The average global sea level has risen 8.9 inches between 1880 and 2015. That’s much faster than in the previous 2,700 years.
SLR is not uniform across the world. Regional SLR may be higher or lower than Global SLR due to subsidence, upstream flood control, erosion, regional ocean currents, variations in land height, and compressive weight of Ice Age glaciers.
