Google Earth Community: Satellite detection of environmental damage

Slide transparancy to see wetland loss since 1839. Overlay image take from: http://www.slld.net/csimage.html

Without its wetlands, the city of New Orleans could not have been born, the bayou and marsh habitats helping to buffer the city from hurricanes and tidal action. As the wetlands disappear, the city in effect gets closer to the gulf. Between 1990 and 2000, wetland loss was approximately 24 square miles per year, the equivalent of about one football field lost every 38 minutes.

"With the rapidly depleting wetlands, people that have lived in southern Louisiana can tell that, over the last 30 years, large storms now come in faster, and the water rises faster, which gives less time to respond and less time to evacuate," said Denise Reed, a professor of geology and geophysics at the University of New Orleans. "In the next few years it's going to get worse."
(Feb. 9, 2005 - http://news.nationalgeographic.com/news/2005/02/0209_050209_wetlands.html )

"The crucial New Orleans marshland that absorbs excess water during storms has been greatly denuded by rampant commercial development allowed by a deregulation-crazy culture that favors a quick buck over long-term community benefits."
From: http://www.latimes.com/news/opinion/commentary/la-oe-scheer6sep06,0,5176600.column?coll=la-news-comment-opinions :

The Lost Coast
from: http://www3.nationalgeographic.com/ngm/0410/feature5/
With the runoff from a third of the nation, the Mississippi River built coastal Louisiana, a swath of marsh, islands, and swamp that covered more than 6,000 square miles (15,500 square kilometers) in the early 20th century. Levees raised in the 1930s ended spring floods that pumped vital sediments and nutrients into wetlands. Then nutria, a South American rodent imported by fur farmers, escaped into the wild and began devouring marsh roots. By the 1960s the U.S. Army Corps of Engineers had dredged 14 major ship channels to inland ports, while oil companies cut countless canals for pipelines and wells, resulting in wetland loss in such areas as Barataria Basin. Add the toll from subsidence and sea-level rise, and Louisiana has lost 1,900 square miles (4,900 square kilometers) of wetlands since the 1930s. With another 700 square miles (1,800 square kilometers) likely to vanish by 2050, the state has proposed an ambitious 14-billion-dollar plan to save what's left. "We ripped the guts out of south Louisiana," says University of New Orleans geologist Shea Penland. "Now we want it back."

From http://www.marshmission.com/problem.cfm :
Over a million acres have disappeared since the 1930s and, at the present loss rate of 24 square miles a year, an additional 500 square miles of coastal land will wash away by 2050. Gone forever will be precious nursery habitat for fish and shellfish; nesting and feeding grounds for migratory waterfowl and wildlife; storm surge protection for vulnerable coastal communities, ports, and roads; and land that buffers oil and gas pipelines, production platforms, and shore-based processing facilities against storm and wave damage. Louisiana's coastal marshes are the cradle of nearly one-third of the total commercial fish and shellfish harvest in the lower 48 states. Seventeen percent of the nation’s oil and twenty-five percent of its natural gas are mined in the state's offshore waters. Louisiana’s four major ports handle more than 21 percent of U.S. foreign waterborne trade. Calling Louisiana’s coastal marshes "a national treasure" is no exaggeration.

We are losing this valuable habitat for several reasons including a lack of sediment being deposited by the Mississippi River, saltwater intrusion into our freshwater marshes, natural waterways being modified by man, boat wakes, and a loss of sediment that is trapped behind dams along the Upper Mississippi River.