“We are defined by our relationship to the water,” says LeaLea VanWinkle-Gisler, a member of the New Orleans Water Collaborative, a large, diverse grassroots movement aimed at better management of water resources. The US city of New Orleans, in the state of Louisiana, is bordered by water on two sides—the Mississippi River on one side and Lake Pontchartrain, a massive estuary and the second largest inland saltwater body in the US, on the other. About 50% of the city lies below sea level.
New Orleans, or NOLA, as many locals refer to the city, has a history steeped in its proximity to the Mississippi, for economic and trade reasons as well as its darker history of slave trade. From the 1700s, people have built canals along the Mississippi to redirect and make the best use of its waters, but have weathered flooding and storms as well. In August 2005, Hurricane Katrina hit the city with devastating impact. A 2018 academic paper in the journal Nature confirmed that climate change worsened the effect of Hurricane Katrina and that hurricanes and cyclones around the world would only wreak greater havoc unless climate change mitigation measures began.
“Katrina pulled back the curtain and let us see the light and the shadow very clearly in New Orleans,” says VanWinkle-Gisler. “A common misconception is that the levees (on the river bank) are huge walls made from concrete or cement, but levees are nothing but large barriers made from earthen materials. When Katrina happened, it was these barriers that washed away, and the people who were the most impacted, who died first, were the people of colour, and those who were poorer.”
To hear her speak is to be reminded of Cyclone Biparjoy’s landfall in Gujarat in June 2023 and the reports that said its impact had been heightened by climate change. About 100,000 people, many of them extremely poor, had to be evacuated, and property, roads and power lines were damaged.
Tropical storms and cyclones are increasing in power and number, and their impact will be felt first in the Indian Ocean region, including the Arabian Sea and Bay of Bengal. With high populations along India’s coastlines, people will be more vulnerable than ever.
Deanna DuPont, a water history manager and environmentalist who is part of the New Orleans Water Collaborative, says, “A new approach to storm management starts at the coast where healthy wetlands reduce the risk of flooding by acting as sponges that capture water and release it slowly.” While New Orleans has made major strides to improve its storm protection systems, continued innovation and environmental action is needed to ensure the city and its people stay safe.
Raghu Murtugudde, an earth system scientist and a visiting professor at Indian Institute of Technology Bombay, explains that the Gulf of Mexico is the warmest water body that far north and is warming rapidly just like the north Indian Ocean. Natural defenses have been decimated there as they have been along our coasts. “Land is sinking there since the last Ice Age in an isostatic rebound following glacier melt and mining of groundwater has accelerated the sinking,” he says. Along India’s coast, sea levels are rising because of ocean warming and the massive sediment loading from rivers. The sediments are pushing the ocean crust down in the northern Bay of Bengal and creating rapid sea level rise.
But cyclones in the north Indian Ocean do not have the space to grow into the kind of monsters that hurricanes over the Atlantic and the Gulf of Mexico do. “Mortalities used to be the highest for cyclones but now India has effectively reduced loss of life due to its investment in cyclone forecasting and early warnings with a much better disaster management,” Murtugudde says. “Vulnerabilities are high even in a rich country like the US because lower rungs of the socioeconomic strata are exposed to risks without the infrastructure and services like transportation and healthcare or even insurance coverage for disasters. This is the same for India.”
In both cases, across oceans, the focus has to be on the humans who are the most vulnerable. “We are hardly alone in the challenge,” DuPont points out. “Many coastal cities around the world, like the ones in India, face similar threats due to rising sea levels and climate driven storm intensity. The solutions and technologies developed in New Orleans will help other coastal cities deal with this increasing threat in the future.”