India is the world’s third-leading CO2 emitter and already faces notable changes to its climate due to global warming, which are very likely to worsen over the next eighty years. The country’s mean temperature rise for 1901-2018 is 0.7ºC/1.3ºF, slightly below the world average of 1.1ºC/2.0 ºF. Precipitation patterns are also changing, in the now-familiar manner of dry zones becoming drier and wet zones becoming erratically wetter.
Temperature anomalies, 1850-2018.
Already in 2022 India and Pakistan have suffered a withering heat wave, with several locations reporting temperatures in March of 42.8°C/109.0°F, with the city of Wardha reporting 45°C/113°F. The heat wave, which made India’s March its hottest since 1901, killed a substantial part of the spring wheat harvest, defeating farmers’ plans to partly offset international wheat shortages due to the war in Ukraine. 25 people in India and 65 in Pakistan are known to have died from the heat, which even caused a bridge collapse in the Hunza Valley when a nearby glacial lake released more meltwater than usual into local streams, softening the ground. Formerly extreme events like these are becoming more common worldwide, as what were previously known as “hundred-year floods” and “hundred-year droughts” are now occurring several times a decade. Nature’s changes are altering our statistical evidence.
Climate projections show warming throughout India, with the savannah of the central plateau moving north into what is now temperate. The Himalaya are projected to continue warming and lose more of their ice and snow. The monoons are expected to bring more rain, but more in pulses, with in a higher number of violent torrents, and less consistent rainfall overall. Meanwhile the Thar Desert in the northwest will become hotter still, as well as the arid steppe region southeast of it, which is predicted to experience more droughts.
Regional climate predictions (Indian Institute of Tropical Meteorology)
Sea level rise has been consistent along India’s entire coast. Between 1993 and 2012 minimum increase rates of 2.5 mm/yr occurred along India’s west coast, and rates as high as 5 mm/yr occurred along much of India’s east coast and along almost all the Bay of Bengal. Only a few stretches of western Indian coastline have been determined to be at high risk of flooding, but that is not the case with Bangladesh, as we will see.
Sea level (a) rise and (b) measurement uncertainty, 1993-2012.
Coastal flood risk.
Tomorrow: introduction to Bangladesh.
Be brave,
and be well.
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