SEA
LEVEL RISE - ENVIRONMENT
News: Has the future sea level rise been
correctly estimated?
What's
in the news?
●
The researchers found that as the
Petermann Glacier’s grounding line retreated nearly 4 km between 2016 and 2022.
●
Warm water carved a 670-foot-tall cavity
in the underside of the glacier, and that abscess remained there for all of
2022.
Key
takeaways:
●
Global mean sea-level increased by 0.20m between 1901 and 2018, with an average rate
increase of 1.3 mm/year between 1901 and 1971,1.9 mm/year between 1971 and
2006, and 3.7 mm/year between 2006 and 2018.
●
Between
2013 and 2022, this has been 4.5 mm/yr and human influence was
very likely the main driver of these increases since at least 1971.
Causes
for Sea Level Rise:
1.
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 simply occupying more space.
2.
Melting glaciers:
●
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.
●
It creates an imbalance between runoff and
ocean evaporation, causing sea levels to rise.
3.
Loss of Greenland and Antarctic ice sheets:
● 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.
4.
Slowing Gulf Stream
Impact
of Rising Sea Levels:
1.
Coastal flooding:
●
Globally, eight of the world’s 10 largest cities are near a coast, which is
threatened by coastal flooding.
●
Jakarta
(Indonesia) is known as the world’s fastest-sinking
city, by about 25 cm into the ground every year.
●
Other cities that regularly feature in the
lists endangered by climate change include Guangzhou, Jakarta, Miami, Mumbai
and Manila.
2.
Destruction of coastal biodiversity:
●
Sea level rise can cause destructive
erosion, wetland flooding, aquifer and agricultural soil contamination with
salt, and lost habitat for biodiversity.
3.
Dangerous storm surges:
●
Higher sea levels are coinciding with more
dangerous hurricanes and typhoons leading to loss of life and property.
4.
Lateral and inland migration:
●
Flooding in low-lying coastal areas is
forcing people to migrate to the higher ground causing displacement and
dispossession and in turn a refugee
crisis worldwide.
5.
Effect on communications infrastructure:
●
The prospect of higher coastal water
levels threatens basic services such as internet
access.
6.
Threat to inland life:
●
Rising seas can contaminate soil and groundwater with salt threatening life farther
away from coasts.
7.
Impacts on tourism:
●
Tourism to coastal areas will also be
negatively affected by an increase in sea level rise.
Mitigation
Measures:
●
Building flood barriers to protect infrastructure
●
Relocate facilities to higher elevations
●
Allow coastal
wetlands to migrate inland (e.g., through setbacks, density restrictions
land purchases)
●
Remove hard protection or other barriers
to tidal and riverine flow (e.g., riverine and tidal dike removals)
●
Incorporate sea level rise into planning
for new infrastructure (e.g., sewage systems)
●
Integrated
Coastal Zone Management - using an integrated approach to
achieve sustainability.
The collaborative efforts
to reduce global warming is the need of the hour to halt the glacier melting and subsequent sea level rising.