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| Left side is chunk that broke off measuring 720km2 |
The past couple weeks there’s
been all kinds of drama on the news: a plane crash in San Francisco, a train
derailment causing an explosion in Québec, President Morsi overthrown in
Egypt, another train derailment in France, etc. But have you heard about the
large ice shelf that broke away from the Pine Island glacier in the Antarctic?
Scientists say that it’s normal for chunks of ice to break
off as cracks form in the ice, especially from Pine Island glacier, because
it’s the fastest flowing glacier in the Western Antarctic. The concern,
however, is that the wind directions have changed in the Amundsen Sea, bringing
warm sea air underneath the shelf, so that it breaks from the bottom. This
leads to the concern that the ice will become unstable and more very large ice
chunks will slide off, going into the ocean and causing sea levels to rise
substantially. The chunk that just broke
away measured 720km2 (about the size of a large city) and is expected to slightly increase the global
sea level.
If the
entire West Antarctic ice shield were to go into the ocean, sea levels would
rise by 3.3 meters, flooding parts of many global cities. Many of the world’s
cities are also along coasts, making them vulnerable. The ten cities deemed
most at risk to sea level rise are:
1. Miami, USA
2. Venice, Italy
3. New York City, USA
4. Mumbai, India
5. Singapore
6. New Orleans, USA
7. Osaka, Japan
8. Tampa, USA
9. Dhaka, Bangladesh
10. Tokyo, Japan
If breaking ice shelves can cause
such a significant impact throughout the world, why aren’t we more concerned?
Is it because melting ice and rising sea levels don’t have the dramatic story
that a plane crash or explosion do or is it just too long term to be a good
news story? Why do you think we’ve become so indifferent and bored of one of
the biggest potential changes in history?
Very interesting! I would have thought that the reason we don't care enough about this issue is that the people who are most affected by it are in developing countries, while those of us who contribute most are in developed countries. That made your list of 10 most at-risk cities all the more puzzling, because most of those are very developed places! I can't figure out why more people aren't concerned, but probably not everyone has seen all of this information.
ReplyDeleteAs Caileigh mentioned I feel as though a lot of the inaction stems from a lack of education. Media tends to avoid sharing stories that aren't of immediate interest. I feel as though a lot of people only pay attention to that which is related to their day to day lives right now, not what could happen 50-100 years from now. Most people don't think about the implications of their actions until they have to live with them.
DeleteYes, of the 10 most at-risk cities, only 2 are considered to be in developing countries (Mumbai & Dhaka). In some of those cities, there are certain measures being taken (e.g. in New York after Hurricane Sandy) but they mostly involve the construction of levees or other small engineered designs, and it does not seem to be a big concern. Part of the problem though, as Danielle said, is that we aren't looking 50-100 years ahead. It's hard for people to plan for something that they likely won't be alive for.
DeleteI think you nailed it right at the end. Sea level change might be happening relatively quickly relative to the age of the Earth, but from a human's frame of reference it's basically so slow that it is imperceptible. It doesn't have the immediate, attention-grabbing impact that a sudden news event does, and so awareness isn't spreading quickly at all. Reminds me of the "boiling frog" metaphor that slow, gradual changes will go unnoticed until it's too late (http://en.wikipedia.org/wiki/Boiling_frog).
ReplyDeleteIce shelves in and of themselves would only slightly affect sea level as they already float, i.e. they displace water as icebergs do. Continental ice, though, would indeed have a huge effect -- on the other hand, it doesn't take a thermodynamics expert to know it would take a very long time to heat up a kilometres-thick continental ice sheet.
If you look back at the geological record that we have been able to uncover, global temperatures and sea levels have been fluctuating dramatically as long as the Earth has existed. Only 20,000 years ago, at the height of the last ice age, sea level was a full 120 metres lower than it is now. The problem is that we, as a society, haven't been around long enough to see or record much of any changes (to this point, anyways).
If drastic climate change continues, will the Earth find a "new normal"? Sure. Will us humans survive it? That, we don't know.
Thanks for your insight Adam! The "boiling frog" metaphor is perfect for describing people's attitudes towards this. By the time most people do pay attention, it will be far too late to do anything about it.
DeleteI also didn't know how low the sea level was during the last ice age! That's really interesting.
As for us humans surviving the "new normal", I do think humankind will survive, but perhaps not in the magnitude that we are today. But humans are very adaptable and even if the world completely changes, there will likely be humans still left.
Hey you're welcome Darrelle! I guess this one just appealed to the geologist in me ... it's crazy to know what massive variations the Earth has seen long before we ever came along. I'm sure human civilization is contributing to climate change, but when far greater fluctuations have taken place for billions of years, how much of an effect can we really be having? We could drop emissions of carbon, etc. to zero and yet we might never affect the end result.
ReplyDelete