As I write this title, it seems a bit counter intuitive that one of the first things I saw this morning was a newspaper discussing many small cities around the Texas Panhandle which are running out of water. And on the TV news as I write this, the city of Amarillo announces measures being taken to curtail water use, followed by a detailed discussion, explaining how one of these smaller towns plans to address the lack of water. Drought expands while ice melts and seas rise.
Childs explains sea behavior by comparing it to pouring water back and forth among a bunch of pans. Ocean behavior varies from place to place. Louisiana has been losing seacoast at the rate of twelve meters per year and large parts of the Nigerian coastline has lost as much as thirty meters per year, one of the fastest losses on earth–erosion. The moon causes tides twice a day changing sea levels on the average of two meters each time. Historically most sea level changes are long term changes. A major cause of sea level change is temperature. Half the current sea level rise can be attributed to thermal expansion. Water warms and spreads out. Not only does heat expand near the sea surface, but now also expands into depths not previously affected. Findings by two oceanographers, Purkey and Johnson, indicate an increase in ocean heat 16 per cent greater than previously thought. Oceans are the largest reservoirs of heat on earth. Once heated, their size makes them slow to cool.
Purkey also notes that even in the depths of the seas, waves transfer heat. However, because of the size of the Pacific, an event that occurred forty years ago in the southern Pacific will not reach the northern Pacific for approximately those forty years. Thus, the warming and subsequent ice melt we see in the north Pacific started in the south Pacific forty years ago. Another scientist, Carl Wunsch, notes that earth changes remarkably without human intervention. Nevertheless, he recommends humans do something to reduce carbon dioxide emissions as a precautionary measure in addition to discouraging people from settling in low lying areas. Unfortunately, rising seas do not bode well for much of the earth’s population who live in exactly these low lying areas: all of Bangladesh, Venice, Shanghai, New Orleans, Bangkok, the Marshall Islands, and many US coastal cities to name just a few places.
St. Lawrence Island north of the Aleutians provides a perfect example of what is happening. Sea ice breaks up too early, fish species they used to see are gone replaced by new ones they never saw before, and the population of seals and sea lions has altered. Cancer rates in the villages there have risen dramatically caused in part by the toxic poisons concentrated in the meat of the seals, whales, and salmon they harvest from our polluted oceans. In 2008, they brought a lawsuit against Exxon, Chevron, and Mobil, claiming that these companies are the world’s major contributors to global warming. They want these companies to pay for moving their villages to higher ground. Sea rise necessitates the move. They lost in District Court, but the case is under appeal. The court cited that the chain of events causing their predicament is too long to lay blame in one place. Childs notes that we really need such places to endure, places where people know how to lead minimalist lives, places where people know how to survive.