New Delhi/Geneva: Extreme sea level events that previously occurred once in 100 years could happen every year by the end of this century, the latest IPCC report on climate change said on Monday with scientists warning that sea level rise, floods, heavy rainfall and glacier melting are some of the irreversible effects.
The Intergovernmental Panel on Climate Change's (IPCC) Sixth Assessment Report (AR6) 'Climate Change 2021: The Physical Science Basis' said every region in the world is witnessing irreversible changes in climate due to human influence.
The report, approved by 195 member governments of the IPCC through virtual sessions held over two weeks since July 26, projected that in the coming decades climate changes will increase in all regions.
Here are some key takeaways
Coastal areas will see continued sea level rise throughout the 21st century, contributing to more frequent and severe coastal flooding in low-lying areas and coastal erosion with extreme sea level events.
It said that for 1.5 degrees Celsius of global warming, there will be increasing heat waves, longer warm seasons and shorter cold seasons. At 2 degrees Celsius of global warming, heat extremes would more often reach critical tolerance thresholds for agriculture and health.
Climate change is affecting rainfall patterns. In high latitudes, precipitation is likely to increase, while it is projected to decrease over large parts of the subtropics. Changes to monsoon precipitation are expected, which will vary by region.
The report, however, gave hope that it is still possible from a physical science point of view, to limit global warming to 1.5 degrees if global emissions are reduced to net zero by 2040 there is still a two-thirds chance to reach 1.5 degrees.
The report said while benefits for air quality would come quickly, it could take 20-30 years to see global temperatures stabilise.
It found that further warming of the earth will amplify permafrost thawing, and the loss of seasonal snow cover, melting of glaciers and ice sheets, and loss of summer Arctic Sea ice.
For cities, some aspects of climate change may be amplified, including heat (since urban areas are usually warmer than their surroundings), flooding from heavy precipitation events and sea level rise in coastal cities, the report said.
The report provides new estimates of the chances of crossing the global warming level of 1.5 degrees Celsius in the next decades, and finds that unless there are immediate, rapid and large-scale reductions in greenhouse gas emissions, limiting warming to close to 1.5 degrees Celsius or even 2 degrees Celsius will be beyond reach.
For the first time, the sixth assessment report provides a more detailed regional assessment of climate change, including a focus on useful information that can inform risk assessment, adaptation, and other decision-making, and a new framework that helps translate physical changes in climate into what they mean for society and ecosystems.
The report showed that human actions still have the potential to determine the future course of climate, saying that the evidence is clear that carbon dioxide is the main driver of climate change, even as other greenhouse gases and air pollutants also affect the climate.
