Some have called for the Thames Barrier — in operation since 1982 — to be replaced or supplemented by an even more ambitious flood defense system farther down the river, but Britain’s Environment Agency says the defenses should hold until 2070.
Meanwhile, environmentally conscious Londoners have made plans to battle some of the other predicted effects of global warming by promoting better water management, expanding the city’s Victorian sewage network and “urban greening” — the planting of trees and rooftop gardens to help manage the urban heat island effect.
Southern Florida is one of those places that show up as partially under water in many sea level projections for this century, so it is no surprise local leaders are seeking ways to adapt. Four counties of South Florida, including Miami-Dade, have collaborated on a regional plan to respond to climate change. Their overarching goal: keeping fresh water inland and salt water away.
The first action plan calls for more public transportation, stemming the flow of seawater into freshwater and managing the region’s unique ecosystems so they can adapt.
Before writing the plan, the counties reviewed regional sea level data and projected a rise of 23cm to 61cm in the next 50 years along a coastline that has already documented a rise of almost 23cm over the past 100 years.
“The rate’s doubled. It would be disingenuous and sloppy and irresponsible not to respond to it,” said Monroe County Administrator Roman Gastesi, who oversees the Florida Keys.
NEW YORK CITY
New York Mayor Michael Bloomberg last week announced one of the most ambitious plans for defending a major US city from climate change. Recommendations range from installing removable flood walls in lower Manhattan to restoring marshes in Jamaica Bay in Queens, and from flood-proofing homes to setting repair timeframe standards for telephone and Internet service providers.
In lower Manhattan, a removable system of posts and slats could be deployed to form temporary flood walls. The height would depend on the ground elevation and potential surge. The approach is used along some Midwestern rivers and in the Netherlands, city officials said.
Projects also include a 4.6m to 6m levee to guard part of Staten Island, building dunes in the Rockaways, building barrier systems of levees and gates to bar one creek from carrying floodwaters inland, and possibly creating a levee and a sizeable new “Seaport City” development in lower Manhattan.
A low-lying delta nation of 153 million people, Bangladesh is one of Asia’s poorest countries, and one that faces extreme risks from rising sea levels. Its capital, Dhaka, is at the top of a list of world cities deemed most vulnerable to climate change, according to a recent survey by risk analysis company Maplecroft. The World Bank says a sea level rise of 14cm would affect 20 million people living along the country’s 710km coast. Many of these people would be homeless.
Bangladesh is implementing two major projects worth US$470 million that involve growing forests on the coastal belt and building more multistory shelters to house people after cyclones and tidal surges. Developed nations have so far provided US$170 million to the fund.
“Bangladesh is opting for adapting to the climate change impacts as the world’s developed nations are not doing enough to cut down carbon emissions,” Forest and Environment Minister Hasan Mahmud said in a recent speech in Dhaka. “We want the donors to contribute more to our efforts.”