If greenhouse gas emissions are not cut drastically and rapidly, between 2030-52, the Earth’s global average temperatures could rise by 1.5 degree above pre-industrial era levels, leading to widespread climate change impacts, the UN climate change science panel report has cautioned. All the countries accepted the report on Saturday after a contentious and strenuous meeting between scientists and diplomats in Korea.
On a jarring note, the US announced that it accepted the report - in effect stopped short of vetoing it - but it did not endorse the content and the findings. It also reasserted that it was determined to step out of the Paris Agreement at the first opportunity.
The US had made a belligerent attempt to dilute the contents of the report along the lines it had planned. This included a push to drop references to how historically accumulated emissions in the atmosphere, and not just the current flow of emissions, have caused climate change. It also objected to references to the emissions being reduced in keeping with the principle of equity and fairness.
The larger import of the report’s findings was not much different from that of the drafts that had leaked earlier, though the negotiations did end up substantially altering how much confidence the governments placed on different findings based on the scientific evidence underlying the summarised take-aways.
The report said, 'Human activities are estimated to have caused approximately 1.0 degree Celsius of global warming above pre-industrial levels, with a likely range of 0.8 degree Celsius to 1.2 degree Celsius. Global warming is likely to reach 1.5 degree Celsius between 2030 and 2052 if it continues to increase at the current rate.'
They summarised that the already recorded rise of 1 degree in global average temperatures has led to substantial impacts. 'Impacts on natural and human systems from global warming have already been observed (high confidence). Many land and ocean ecosystems and some of the services they provide have already changed due to global warming (high confidence).'
A rise in global temperatures by another 0.5 degree Celsius would increase, deepen and spread the impacts wider, the scientists concluded. 'Several regional changes in climate are assessed to occur with global warming up to 1.5 degree Celsius compared to pre-industrial levels, including warming of extreme temperatures in many regions (high confidence), increases in frequency, intensity, and/or amount of heavy precipitation in several regions (high confidence), and an increase in intensity or frequency of droughts in some regions (medium confidence).'
The report laid out how the changes to climate, environment and human life would be less devastating and dangerous if the global temperature rise is contained at below 1.5 degree instead of 2 degree Celsius - the existing primary goal of the Paris Agreement.
Several countries have advocated at the negotiations to implement the Paris Agreement. This would require all countries to enhance their existing emission reduction targets under the agreement for the period starting 2020. It would also require developed countries to contribute more to global finance flows and technology sharing for poor countries to achieve these enhanced targets.