"Going Coastal"

By Daria Blackwell

Long Island environs at night and by day (NASA)

Are human settlements reaching "coastal saturation"?

Centers of human population (i.e., cities) historically have been located on coastlines because there are many benefits, including transportation, food sources, commerce, and recreation. The result has been a natural migration of populations toward coastal areas.  The problem is that we may be reaching “coastal saturation,” a phenomenon that is putting huge ecological pressure on our coastal regions.

At the beginning of this century, the world's population was less than two billion.  By about October 12, 1999 , the human population had tripled to six billion.  The sixth billion took a record low of 12 years to be born, from 1987 to 1999.  The global population is on course to increase to ten billion (10,000,000,000) by 2030 (or sooner).  

Today, more people than inhabited the entire globe in 1950 - 44% of the world's population - live within 100 miles of the coast. The rate of population growth in coastal areas is accelerating; in 2001 over half the world's population lived within 125 miles of a coastline.  One example of this incredible growth is Casablanca , wh ich saw its population soar from 600 in 1839 to 29,000 in 1900 and to almost 5 million today.

In the United States , more than half the population (about 53%) lives near the coast and since 1970 there have been 2000 homes per day erected in coastal areas. In China alone, where the urban population is expected to increase by over 125% in the next twenty-five years, more than 400 million live on the coast. In fact, according to UN 2005 statistics, eight of the top ten largest cities in the world are located by the coast. We just keep on going coastal!

Top Ten Largest Cities:

1. Tokyo , Japan - Coastal
2. Mexico City , Mexico - Inland
3. Mumbai , India - Coastal
4. Sáo Paulo , Brazil - Inland
5. New York City , USA - Coastal
6. Shanghai , China - Coastal
7. Lagos , Nigeria - Coastal
8. Los Angeles , USA - Coastal
9. Calcutta , India - Coastal
10. Buenos Aires , Argentina - Coastal

Coastal areas are some of the most productive and biologically diverse on the planet. Of the 13,200 known species of marine fish, almost 80% are coastal. The oceans play a crucial role in maintaining the health of the earth's ecosystems and serve as an important food source. Ironically, the great productivity of coastal areas is what attracts these abundant populations, making them party to their own destruction.

The more people that crowd into coastal areas, the more pressure they impose both on land and sea. Natural landscapes are altered and overwhelmed, coastal habitats are 'reclaimed', wetlands are drained and covered with trash, the floodplains around estuaries are built over and reduced, and mangroves and other forests are cut down. Entire ecosystems are damaged, frequently lost forever. Fish stocks, fresh water, soils and beach sands are often overexploited. Increasing volumes of waste, particularly sewage, are sluiced out into coastal waters. Rubbish is often dumped on important habitats which are destroyed while contaminants leach into coastal waters.

With this kind of pressure, it’s small wonder that our oceans and coastal waters are suffering.  It’s not too late though.  Those of you who are old enough will remember the film footage of Lake Erie on fire and widespread fish kills on other waters.  In those days, the beaches were never closed because they were not monitored. In those days, the rockfish left and the oysters died in the Chesapeake, Long Island Sound was very nearly dead altogether, and Rachel Carson sent the world a wake up call with Silent Spring.  We’re doing a better job today than we were then, but we are still far away from the ideal situation where we can live in harmony on the edge of the place where the land meets the sea. If we are going to preserve the sea that we love to sail on so much, we need to be aware of these things.

Hey, better yet, let's all do something about it. One person, one thing. Pretty soon those 10 billion things will add up. As sailors, we already do one small part the moment we raise our sails and shut off our engines. So let's enjoy our coastal sailing territory and do what we can to protect it. Now that's "going coastal"!

• Read more about the US coastal population trends in NOAA's highly informative report "Population Trends Along the Coastal United States: 1980-2008."
• Much of the data presented here are from the UN Atlas of the Oceans, one of the best places to start learning about the sea around us.  http://www.oceansatlas.org/
  
  

Global light pollution from the Leander McCormick Observatory archives shows concentrations of population along coastal areas, lakes and rivers.

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