Rising Seas

Over the course of the last week, we've been hearing a lot about the devastating monsoons in Bangladesh. The recent storm swept far inland, and as I wrote this article, the projected death toll was in the area of around 250,000. It's difficult for us to imagine, as we sit in our comfortable homes in Canmore, but it may only be a sign of worse times to come as the world's climate rapidly begins to warm.

With the projected changes caused by the greenhouse effect, world temperatures will continue to climb over the next 50 years until they reach levels higher than those experienced over the last two million years. For instance, as the level of carbon dioxide (CO²) doubles it will increase the global temperature by around 5°C. In the mid and upper latitudes, like Canmore, the temperature rise will be even more rapid--almost twice the global average. We could see a rise of as much as 1°C per decade.

Although scientists agree that temperatures will likely rise, there is still strong debate as to the exact rate of increase. In addition, warmer temperatures will bring about much more variability in the weather, as the dramatic storms of the last few years have shown. It is well known that increases in ocean surface temperatures can cause increases in both the severity and the frequency of tropical storms and hurricanes.

Another unpleasant side benefit of global warming will be a rise in sea level. At a time when the world is continually seeming smaller and smaller, it will only get worse as large areas of the Earth's surface slip below the waves. According to the U.S. Environmental Protection Agency, there could be a rise of as much as 2.2 metres by the year 2100.

As the water level rises huge coastal areas would disappear. In addition, since most coastal areas are very densely populated, millions would be displaced. These environmental refugees would have to be moved to areas of already heavy crowding. For instance a rise of only a half metre would displace 16% of Egypt's population. A rise of two metres would flood more than a quarter of the land mass of Bangladesh--not to mention large portions of Louisiana and Florida.

The costs of holding back the seas would be insurmountable for most large coastal cities. Charleston, South Carolina would have to fork out over a billion and a half dollars to protect itself from a rise of only a metre.

Another devastating result of rising sea levels would be the infiltration of salt into many fresh water supplies as well as the flooding of a large portion of Asia's food growing areas. Since rice is grown in low lying river deltas, much of the most critical rice growing areas would be invaded and rendered useless. The potential ramifications are endless.