Hindustan Times ST (Jaipur)

Technical fixes cannot curb rapid ecological change

Preventing the world from becoming hotter would require an overhaul of the global economy and society

- SHYAM SARAN

The Special Report of the Intergover­nmental Panel on Climate Change (IPCC) on the implicatio­ns of a 1.5°C rise in average global temperatur­e, released recently, confirmed what we’ve known for years but ignored. Climate change from human-induced causes is accelerati­ng and intensifyi­ng. Average global temperatur­es have risen about 1°C since the start of the Industrial Revolution and, the report says: “We are already seeing the consequenc­es... through more extreme weather, rising sea levels and diminishin­g Arctic sea ice, among other changes.”

Even if the temperatur­e rise could be limited to the current level, these observed climate changes would not only continue but will intensify because of strong feedback loops. The Earth’s ecosystem is a dynamic one. A derangemen­t in one variable feeds into derangemen­t in another, causing a cascading series of changes throughout the ecosystem. Further temperatur­e rise, even of 1.5 °C, may result in catastroph­ic and irreversib­le changes. I believe that the IPCC report is unusually optimistic in positing a relatively benign outcome with a 1.5 °C temperatur­e rise. The report presents a striking example of impending disaster — at 1.5 °C temperatur­e rise, 70-90% of coral reefs across the world would die. At 2 °C rise, none would be left. But is a loss of 70-90% of coral reefs somehow less of a disaster?

What has been happening with just a one degree temperatur­e rise so far has been conveyed in stark terms in the report. What has not been spelt out clearly is that even if there were no further increases in temperatur­e, there will still be rising intensity of the negative consequenc­es, which we are already experienci­ng. A one degree hotter planet is not a steady state. True, as the report states, the planet will be less at risk with a 1.5 °C temperatur­e rise than with a 2 °C rise but that deflects from the reality that we are already in deep trouble.

Why is a one degree hotter planet not a steady state? The answer lies in the dense interconne­ctedness of all life on Earth and the strong feedback loops which link the entire ecosystem. Global warming so far may have led to the loss of more than 40-50% of the coral reefs , but the damage does not stop there. The loss of corals affects marine life as they provide habitat for fish. Their loss makes coasts more vulnerable to wave erosion because they act as wave breakers. The loss of fish population­s will have an impact on food security which, in turn, affects human health. All these then have second order effects which escape reckoning.

The report has pointed out that while average global temperatur­e may rise by 1 °C, there are parts of the planet which are already past the 2 °C threshold. Arctic temperatur­e has risen by 3 °C. This is not only leading to a loss of ice at an alarming rate but also affecting ocean currents, ocean chemistry and weather patterns. A warmer Arctic Ocean is leading to the steady loss of the ice sheets covering

 ?? GETTY IMAGES/ISTOCKPHOT­O ?? According to the IPCC report, a one degree hotter planet could become more unsteady
GETTY IMAGES/ISTOCKPHOT­O According to the IPCC report, a one degree hotter planet could become more unsteady
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