Monday, 14 May 2012

60-90% chance of Bangladesh sinking under rising sea levels

This article was published in the Financial Express in Bangladesh.

“Science as a Contact Sport; inside the battle to save Earth's climate” by Stephen Schneider is an illuminating book by a world renowned climate scientist and professor at the Woods Institute for the Environment at Stanford University. In 2007, Schneider received the Nobel Peace Price on behalf of the International Panel for Climate Change (IPCC), along with Al Gore. His book is a recounting of his efforts over three decades to get the US government and the rest of the world to pay attention to climate change science.

The basic question which climate science has tried to answer is: how serious is climate change? But communicating a scientific answer to this question has been impossible, Schneider says, as politicians, journalists and the average person on the street does not understand that scientific predictions and models of climate change can only predict probabilities of particular outcomes. Unfortunately, the public and the politicians have shown little desire to understand the significance of these scientific probabilities. Instead, they are generally interested in climate science only the extent that it supports their own pre-conceived political beliefs that climate change is insignificant.

If the above sounds familiar, a particular example for which Schneider presents some numbers should frighten all of us. For low-lying countries like Bangladesh, one of the critical questions of climate change is how high sea level rise will be. The answer to this actually depends on whether or not the Greenland ice cap melts; this event would release enough water to raise global sea levels about 25 metres (about 80 feet). This would be the end for Bangladesh, sinking perhaps 75% of the country. It would also be the end of most of the world’s coastal cities like New York, Los Angeles, Washington DC and London. Here are Schneider’s estimates of how likely this is:

For Greenland to irreversibly melt, my own [estimate] would be roughly a 2 to 5 percent chance that it is already too late and it will happen over the long run. At 1 degree Celsius more warming, I’d raise the odds to 25 percent..." (page 274)

So this is the problem of climate science in a nutshell; the likelihood of a major catastrophe like 25 meter sea level rise could be theoretically be as low as 2 to 5 percent. So in the US, Republican politicians like George W. Bush as well as numerous Democrats whose political campaigns rely on donations from oil and coal companies will always focus on the 2 percent probability and dismiss climate change a waste of time. However, for those of us who have not been paid off and can think for ourselves, the rest of the sentence should be shocking:

"...and at 2 degrees Celsius to 60 percent, at 3 degrees Celsius to 90 percent, and so on.” (page 274 continued).

Critically, the basis for all international climate negotiations is to limit global warming to 2 degrees Celsius (as most governments in the world have already decided that it would be too expensive to do anything more than that). This international consensus means that 2 degrees of warming is inevitable, as everyone has accepted that it will happen and will not even try to prevent it. Given that fact, Schneider’s odds for a 25 metre sea level rise and the destruction of Bangladesh becomes 60% to 90% (the 90% figure is still relevant, as it is always possible for countries to fail to cut carbon dioxide emissions enough to limit global warming to 2 degrees).

What to do now? The only people who care about Bangladesh and have the capacity to change anything are Bangladeshis living in Western countries. If they really care about Bangladesh, they should all become climate activists and pressure their governments to do something to prevent this. People in Bangladesh have only two options; firstly, invest vastly more in education and hope people can emigrate before the country sinks. Secondly, invest vastly more in birth control, targeting a 22nd century population of only the 25 million people, which would be the maximum number that the country could support if it was reduced to pockets of high land in Rajshahi division and Chittagong Hill Tracts. Unfortunately, Professor Schneider died from cancer in 2010, and now there is one fewer climate scientist to tell us how we can save ourselves from catastrophic global warming.