Scary sea level rise: now irreversible?

Hey guys, you may have seen recent news articles on the imminent and potentially irreversible collapse of the West Antarctic glaciers (see here). This is a really important subject, so I thought I’d write a bit about it…

Big glaciers in West Antarctica are slowly being taken by the sea. (Reproduced from: http://www.independentaustralia.net/environment/environment-display/no-way-back-for-west-antarctic-glaciers,6510)
Big glaciers in West Antarctica are slowly being taken by the sea. Reproduced from: http://www.independentaustralia.net/environment/environment-display/no-way-back-for-west-antarctic-glaciers,6510

Everyone is aware that global warming has been causing the melting of glaciers, ice on land which stretches out to sea. When glaciers melt, the water runs into the sea causing the global sea level to rise. This is a scary phenomenon considering that loads of cities and communities worldwide are positioned very close to the current sea level. During the 21st century, sea level may have rose up by up to 0.5m. In islands in the Pacific, residents have already been moved from shallower to higher islands as the sea level climbs. 

Pacific Islands like Kiribati are already dangerously close to the sea level, bad news for its residents. (Reproduced from: http://www.telegraph.co.uk/news/worldnews/australiaandthepacific/kiribati/9127576/Entire-nation-of-Kiribati-to-be-relocated-over-rising-sea-level-threat.html)
Pacific Islands like Kiribati are already dangerously close to the sea level, bad news for their residents… Reproduced from: http://www.telegraph.co.uk/news/worldnews/australiaandthepacific/kiribati/9127576/Entire-nation-of-Kiribati-to-be-relocated-over-rising-sea-level-threat.html

The amount of water stored as ice in Antarctic glaciers (the biggest in the world) is absolutely enormous. Antarctic ice is over 4.2 kilometers (2.6 miles) thick in some areas. In the past, scientists reckoned that these massive glaciers were pretty resilient and would remain around for a few thousand years, despite our persistent release of dangerous gases into the atmosphere.

However, scientists from NASA recently suggested that they are more sensitive than we thought, and that warming is melting away the bottom of the ice shelf. They say that melting is now irreversible, meaning that even if we can stop heating our planet, they will be gone anyway in the next millennium. The effect on sea level could be a rise of 3 meters. Further rates of global warming than we have now will only make the problem worse, in which case the glaciers could be gone in a couple of hundred years.

Hundreds of millions of people worldwide living in coastal communities will be at risk, particularly in Asia, and also closer to home in cities such as New York.

The Big Apple is also close to the sea...
The Big Apple is also close to the sea…

Melting of the six West Antarctic glaciers has reached a “point of no return”, mainly due to winds (possibly made stronger by climate change), stirring up the sea water below the glaciers and bringing warmer water from depths of hundreds of meters up to the vicinity of the bottoms of the glaciers. This melts the ice from underneath, a phenomenon which was not always appreciated. Combined with melting from the tops and sides, we can expect very rapid degradation.

But on the other hand, if we can manage to reduce our carbon dioxide emissions we are looking at several hundreds of years until total collapse. In that time, new technological developments will come along, and really help us to protect our coasts from these sea level rises, which is positive. Many places have been developing strategies to help defend against the increasing sea levels. These include building tall walls by the coast.

A seawall in Galveston, Texas blocking the access of the sea. More of these could be required in different places. Reproduced from: http://blog.ucsusa.org/talking-about-sea-level-rise-leading-scientists-meet-in-galveston-texas-114
A seawall in Galveston, Texas, blocking the access of the sea. More of these could be required in different places. Reproduced from: http://blog.ucsusa.org/talking-about-sea-level-rise-leading-scientists-meet-in-galveston-texas-114

I think it’s essential to stay positive, but just to get involved where possibly to understand the real problems facing mankind…

Jx

 

References

Main source: http://www.latimes.com/science/environment/la-sci-0513-antarctic-ice-sheet-20140513-story.html

Cool facts about glaciers: http://nsidc.org/cryosphere/glaciers/quickfacts.html

Cities at risk: http://www.cbc.ca/news/technology/cities-at-risk-from-rising-sea-levels-scientists-say-1.668166

Unstoppable?: http://www.vox.com/2014/5/12/5710440/the-collapse-of-west-antarcticas-glaciers-appears-unstoppable

Adaptation to sea level rise: https://www.e-education.psu.edu/meteo469/node/220

0 Comments
Be the first to leave a reply!

Leave a Comment

* required