Human activity ‘unequivocally’ causing climate change – and we can still influence it, IPCC says in latest report

09 NOV 2021
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Human activities are ‘unequivocally’ the cause of the climate crisis, according to the latest report from the Intergovernmental Panel on Climate Change (IPCC), the world’s leading authority on climate science. Climate change is being observed in every region of the world, and across the entire climate system, with some of the changes, such as rising sea levels, being irreversible, scientists said.   

However, “strong and sustained reductions in emissions of carbon dioxide (CO2) and other greenhouse gases would limit climate change,” the IPC said, although it warned that “unless there are immediate, rapid and large-scale reductions in greenhouse gas emissions, limiting warming to close to 1.5°C or even 2°C will be beyond reach.” 

For the first time, the report includes a dedicated chapter on the increasing incidence of extreme weather events globally, stating that anthropogenic greenhouse gas emissions have “led to an increased frequency and/or intensity of some weather and climate extremes since pre-industrial times.”   
The report also suggests that the threshold for global warming above 1.5°C could be exceeded in the early 2030s, under a moderate emissions climate-modelling scenario unless appropriate and rapid large-scale mitigation takes place in the next decades. 

“Climate change is already affecting every region on Earth, in multiple ways. The changes we experience will increase with additional warming,” said IPCC Working Group I Co-Chair Panmao Zhai.
Warming of 2°C is likely to take place with a range of 2037-2084, under moderate Shared Socioeconomic Pathways (SSP) scenarios, and with a range of 2035-2062, under the high emissions SSP scenario. The SSPs are different scenarios modelled by scientists and based on different situations for climate change mitigation and adaptation.

“Stabilizing the climate will require strong, rapid, and sustained reductions in greenhouse gas emissions, and reaching net zero CO2 emissions. Limiting other greenhouse gases and air pollutants, especially methane, could have benefits both for health and the climate,”

Focusing on the Middle East, the report cites that observed changes in hot extremes has increased and there is medium confidence in human contribution to the observed changes on the Arabian Peninsula. It also states that there has been “an observed annual precipitation decline over the peninsula since the 1980s of 6.3 mm per decade.” 

However, further water cycle changes are expected toward the end of the century with climate change models predicting an increase in annual precipitation over the southern Arabian Peninsula and a decrease over the northern Arabian Peninsula to 2100.

In general, the Arabian Peninsula is also likely to see an increase in intensity and frequency of hot extremes and a decrease in intensity and frequency of cold extremes to the end of the century.