Time is running out to keep global warming below 1.5°C since pre-industrial era levels
The Intergovernmental Panel on Climate Change has come out with a clear scientific consensus that calls for a reversal of man-made greenhouse gas emissions, to prevent severe harm to humanity in the decades ahead. World leaders have been looking for greater clarity on the impact of accumulating emissions on climate. The IPCC’s special report on global warming of 1.5°C, prepared as a follow-up to the UN Paris Agreement on Climate Change, provides the scientific basis for them to act. There is now greater confidence in time-bound projections on the impacts of climate change on agriculture, health, water security and extreme weather. With sound policies, the world can still pull back, although major progress must be achieved by 2030. Governments should achieve net zero CO2 addition to the atmosphere, balancing man-made emissions through removal of CO2. There is public support for this and governments must go even beyond what they have committed to. The Paris Agreement aims to keep global temperature rise in this century well below 2°C compared to pre-industrial levels and pursue efforts to limit the increase even further, to 1.5°C. The IPCC makes it clear that the human and economic costs of a 2°C rise are far greater than for 1.5°C, and the need for action is urgent. Human activity has warmed the world by 1°C over the pre-industrial level and with another half-degree rise, many regions will have warmer extreme temperatures, raising the frequency, intensity and amount of rain or severity of drought. Risks to food security and water, heat exposure, drought and coastal submergence all increase significantly even for a 1.5°C rise. India, Pakistan and China are already suffering moderate effects of warming in areas such as water availability, food production and land degradation, and these will worsen, as the report says. Closer to a 2°C increase, these impacts are expected to spread to sub-Saharan Africa, and West and East Asia. The prognosis for India, of annual heatwaves by mid-century in a scenario of temperature increase in the 1.5°C to 2°C range, is particularly worrying. There is evidence to show it is among the regions that would experience the largest reductions in economic growth in a 2°C scenario. These are clear pointers, and the sensible course for national policy would be to fast-track the emissions reduction pledges made for the Paris Agreement. The commitment to generate 100 GW of solar energy by 2022 should lead to a quick scale-up from the 24 GW installed, and cutting down of coal use. Agriculture needs to be strengthened with policies that improve water conservation, and afforestation should help create a large carbon sink. There is a crucial role for all the States, since their decisions will have a lock-in effect.