Ocean warming to impact food production in India, elsewhere: Report

Report warns of impact on yields and calls it the greatest hidden challenge for the current generation

Food security of India and several other major key food producing countries is threatened by changing weather patterns due to warming of the oceans, which may well be the "greatest" hidden challenge for the present generation, according to a study.

"The consequences for society of changing weather patterns due to the warming of the oceans are considerable," said the report titled 'Explaining ocean warming: causes, scale, effects and consequences'.

The report, released by the International Union for Conservation of Nature, said they involve a mix of food and water factors, and the evolution of various types of risk.

Noting that there have already been changes to precipitation patterns in a number of areas of the planet resulting from large-scale atmospheric teleconnections with ocean warming, the report said there can be increased rainfall in some mid-latitude and monsoon areas and decrease over various sub-tropical regions.

"Both will have impacts on the yields of crops over a range of important food producing areas such as Australia, North America and India," it said.

The report said there were good correlations between wheat and maize yields with the NAO (North Atlantic Oscillation) and PDO (Pacific Decadal Oscillation), so changes in these ocean-focused atmospheric patterns have direct implications on food production.

Similarly, increasing temperatures tend to reduce maize yields, if all other factors are held constant, it said. "At sea, warming temperatures will cause changes to the abundance and range of marine species used for food, leading to implications for both the billion people who depend on fish for their principal source of protein and the fishing and aquaculture industries linked to this harvesting," the report said.

It also warned that the changes in the ocean are happening between 1.5 to five times faster than those on land. "Such range shifts are potentially irreversible, with great impacts on ecosystems. What this will result in, decades down the line, is less clear," it added.

"It is an experiment where, rather than being a casual observer in the lab, we have unwittingly placed ourselves inside the test-tube," it said, adding that ocean warming may well turn out to be the greatest hidden challenge of our generation.