By How Much Are Sea Levels Rising? Lack Of Local Data Hampers Insight

The Mumbai Climate Action Plan, released in March, assesses a wealth of climate data for the city including temperature, rainfall, and coastal erosion.

- Vaishnavi Chandrashekhar

But the analysis is relatively sparse for a major climate threat: On sea-level rise, it simply cites global projections for the future. "Due to a lack of coastal data for the Mumbai coast," it says, "it is tough to establish sea-level rise as a current risk for the city."

That may seem surprising given all the talk about Mumbai's risk of submergence. But most sea-level rise projections are global or regional, and while these are not wrong, they don't capture the full picture on the ground, say researchers. "What researchers usually do is take global or regional datasets and apply them to a particular region. But that doesn't capture local processes," says Raj Bhagat Palanichamy, geoanalytics manager at World Resources Institute, who worked on the assessment. He adds, "From a data point of view, we didn't have enough evidence to talk about Mumbai."

Researchers say better monitoring of coastal processes as well as more accessible data are needed to truly understand the impact of sea-level rise in the city. Without localised insights, says Bhagat, "it's going to be hard to plan for Mumbai."