The report, which applied existing climate data to cities such as New Orleans, was financed by grant from the federal Environmental Protection Agency, although the agency has not endorsed its findings.
Much of the threat to New Orleans and south Louisiana stems from predictions that increased temperatures will cause the Gulf of Mexico to rise, which will result in the loss of 4,500 square miles of wetlands along the state’s shoreline, according to the report. That’s equal to half of the wetlands loss expected to occur in the United States as a result of climate change, the report said, and compares to the 1,500 square miles of wetlands lost in Louisiana during the past 50 years.
Many scientists believe climate change, fueled by increased concentrations of carbon dioxide in the atmosphere, will cause melting of the polar ice caps and an expansion in the size of water molecules in the world’s oceans, resulting in a rise of 3 feet in the average height of the world’s seas by 2100.
Scientist believe Louisiana will see the results of such sea level rise more quickly because the state’s coastline already is sinking faster than other coastal areas. The report says warmer Gulf water also would disrupt the state’s shrimp industry. White shrimp would not be able to thrive. And while the higher temperatures might boost production of brown shrimp, the loss of wetlands due to sea level rise would more than wipe out any gains. The amount of shrimp produces each year depends on the amount of wetlands available as habitat.
The result could be the collapse of the state’s shrimping industry, the report said.
The loss of wetlands also would remove buffers to storm surge caused by hurricanes and winter storms. As the wetland loss increases, the height and power of such surges will grow and increase the chances that levees will be overwhelmed, the report said. A similar report issued last month by the Coalition to Restore Coastal Louisiana that focused on the effects of lost wetlands concluded that the potential cost of such changes could be as much as $14 billion.
That money would include the cost of relocating or rebuilding oilfield equipment, pipelines and port facilities that now are protected by wetlands; cleaning up oil spills caused by increased storm surges; increasing the height and strength of levees throughout southern Louisiana; and rebuilding or protecting hurricane evacuation routes. It also would include increased costs to the public to insure homes, building and other property liable to hurricane and storm damage.
Paul Templet, a professor of environmental studies at Louisiana State University, said Louisiana actually plays a significant role in causing climate change, a result of its many petrochemical plants. The plants use cheap energy sources that produce as much as 1 percent of the carbon dioxide produced in the world.
That’s about 5 percent of the carbon dioxide produced in the United States, which is responsible for 25 percent of the gas produced worldwide.
Templet said the state needs to recognize the link between its carbon dioxide production and the effects of wetland loss on its future economy. He wants the Legislature to adopt a tax that would increase the cost of energy used by petrochemical industries.
The price increase caused y the tax would force those industries to cut carbon dioxide emissions, he said.
Gary Groesch, executive director of the New Orleans-based Alliance for Affordable Energy, and a contributor to the report, said increased temperatures in Louisiana caused by climate change could result in significant losses for the state’s farmers during the next century. He said the state got a taste of such effects last year, when a drought resulted in losses of $450 million for the state’s corn, cotton, hay, sorghum and soybean crops.
“We believe agriculture may be the part of Louisiana’s economy hurt faster by global warming, even more than the shrimp industry,” he said.