Zee Evans, National Science Foundation
After crossing the legendary Drake Passage, we came in sight of the Antarctic continent. It is a majestic, otherworldly place. The Antarctic Peninsula, which juts northward toward South America, is lined with ice-covered mountains and surrounded by abundant wildlife in the sea. But even on this continent that looks and feels pristine, a troubling process is underway because of global warming.
The ice on land is melting at a faster rate and large ice sheets are moving toward the ocean more rapidly. As a result, sea levels are rising worldwide. Most of the world’s ice is contained in Antarctica – more than 90 percent. The West Antarctic Ice Sheet, which lies south of the Peninsula, contains enough water to raise sea levels worldwide by more than 20 feet. Part of the ice sheet, the Pine Island Glacier ice shelf, is among the many in Antarctica that are shrinking at an accelerating rate. This has direct consequences for low-lying coastal and island communities all over the world – and for their inland neighbors.
In analyzing the relationship between melting ice and sea level rise, it is important to distinguish between two kinds of ice: the ice on land and the ice floating on top of the sea. When floating ice melts, sea level is not affected, because its weight has already pushed the sea level upward. But the melting of glaciers and ice sheets resting on land does increase sea level rise. So far, the melting of small mountain glaciers and portions of ice sheets in Antarctica and Greenland has been the main contributor to sea level rise from the loss of ice. (As the oceans warm up, their volume naturally expands, and this too has been a contributor to a small portion of the sea level rise that has occurred in the age of global warming).
Scientists aren’t yet sure precisely how much sea levels will rise over the next century. What we do know is that sea level rise is occurring already, with real consequences for human beings who live near the coasts. In the world’s largest port cities, 40 million people are now already at risk of severe coastal flooding. That number could well triple within the next half-century or so.
Zee Evans, National Science Foundation
But the most vulnerable regions lie in developing countries, where populations are still rising fast and there is little money to shore up infrastructure. The cities most threatened by sea level rise are places like Calcutta and Mumbai in India; Guangzhou, China; and Ho Chi Minh City, Vietnam. And of course, there are more than a few low-lying island nations – like the Maldives – that are already in imminent danger.
Then there is Bangladesh. A one-meter sea level rise – which could happen as soon as 2050 according to some Antarctic specialists – could result in between 22 and 35 million people in Bangladesh relocating from the areas in which they now live and work. Two-thirds of this nation is less than five meters above sea level. For the nation’s 142 million people packed into a small space, climate change poses a nearly unimaginable challenge. The threat of sea level rise is not simply flooding, but saltwater intrusion that hurts the production of rice, the country’s staple crop. Increased damage to rice farmers could soon put 20 million farmers out of work and force them into crowded cities.
Here in Antarctica, it’s easy to feel isolated from the rest of the world. But as I look at this exquisite continent buried deep under the ice, it’s troubling to think about what will happen as this ice melts ever more rapidly.
Jan Moore
January 31st
What an incredibly written account of the truth of this. I knew we would hear this truth in this way from you. This is why I love you so much. Your passion for this is evident in your writing and your actions. And yes, island nations like Kiribati, Vanuatu and the Carteret Islands as well as Bangladesh are already seeing refugees and feeling the effects not only of sea level rise but of subsidence. This while the hydrologic cycle continues to be fed by our overconsumption. And we are not nearly prepared for the influx of climate refugees due to this. The connection between what is happening in Antarctica and how it effects the rest of the world in our own lives is crucial to see now. Your writing on this is something I have alwasy treasured and frankly have missed. Please do not ever be silent. You inspire me to keep talking about this as well. I may sometimes be opinionated and maybe harsh in my comments but that is only because I care so deeply about this world and our future as I know you do too and see the clock ticking. I sure wsih I could have experienced seeing the splendor of Antarctica’s beauty even amongst the effects we see taking place. Thank you for making it so real. Namaste.
David Hone
January 31st
Congratulations on mounting this expedition. I went to Antarctica in 2009 with Robert Swan and 2041 (an NGO dedicated to the preservation of Antarctica) and was truly inspired by the grandeur of this continent and the important message it is telling us about climate change and the impact it will have on the global sea level budget.
But the story isn’t just about Antarctica, although in the longer term this will be the major contributor to sea level rise if we don’t begin to manage emissions. Today the change in sea level is a combination of thermal expansion, melting of ice sheets (Greenland and Antarctica), disappearance of land ice and, surprisingly for me, groundwater depletion (although this is largely countered by dam retention). The latter contributes over 10% of the current sea level rise, just slightly less than Antarctica at about 14% of the 3+ mm/year.
James Cliborn
February 1st
I would respectfully bring to your attention a seemingly oft-overlooked area: the Central Valley, a.k.a. the San Joaquin Valley, of California. A huge amount of it lies at sea level as far eastward as Sacramento and Stockton and some areas in the “Delta” are below sea level. I would include this area a potential immanent disaster zone for even a minimal increase of sea level. Thanks, Jim
Jan Juffermans
February 1st
Thank you very much mr. Al Gore for your clear message again! Please go on with the facts and the warnings.The UN must now announce the state of emergency on our planet. Already 350.000 climate related deaths are counted per year! And of course every year more and more refugees and damage (See The Climate Vulnerability Monitor 2010, by DARA). It has become evident that planning for example new coal plants, exploring shale gas or any other act to add even more climate gasses to the atmosphere, has become an act of Ecocide. We need the judges now to stop the destruction of our basic life conditions, as a violation of the Universal Human Rights.
mary lukowski
February 1st
I have been keeping up on this global issue. While I was at school in the sixty’s they discussed this. Not a lot…but it was up for discussion. Weather would change as far a where the rain would most likely be worse..such as the coast along New York and down to the Carolinas. It was mentioned that in years to come this area would be somewhat under water…at least 4 to 8 feet…The snow chain would also change so that they would see more accumulation…and the midwest would see less…THere was no mention of ozone as I am not sure many new about it. I also read lately that this warming trend is a prelude to an ice age. As the weather gets warmer in areas and the ice melts if offsets with the oceans and an accurance occurs..not sure what it is called…which in the end would start a new ice age…no doubt if humanity would survive they would have to developed ways to live in these conditions….interesting…
Dennis Tate
February 10th
I am of the opinion that we need to discuss a massive program of solar desalination of ocean waters to invest in producing food in the world’s desert areas.
Every cubic meter of water added to the water table of North Africa, the Middle East, California or Australia will NOT be on top of Florida, New Orleans, Bangladesh or The Netherlands!