Scientists Prepare Climate Change Report Amid Extreme Events

The BBC article “Climate change: Researchers begin discussions on vital report” reports that top scientists and representatives from 195 governments are meeting virtually to finalise a critical climate science study amid the backdrop of extreme events happening in many parts of the world.

According to the article, the report will be a “wake-up call” to governments. This refers to the 40-page Summary for Policymakers, which will become an essential guide to government leaders who will gather in Glasgow this November for the COP26 to discuss critical climate questions and craft policies around the environment, greenhouse gas emissions, infrastructure, and public services.

Reuters reports that scientists with the Intergovernmental Panel on Climate Change (IPCC) will finalise the first instalment of its sixth Assessment Report (AR) in the next two weeks. The report “will update the established science around greenhouse gas emissions and projections for future warming and its impacts” and “will expand on the last IPCC report in 2013 by focusing more on extreme weather and regional impacts”.

Significance of the 2013 IPCC Report

The 2013 IPCC report shows that humans have been the dominant cause of global warming since the 1950s. This report is also the basis for the Paris Climate Agreement 2015, a legally binding international treaty on climate change that requires countries to commit to reducing their GHG emissions through economic and social transformation. In 2018, the IPCC released a special report on keeping global temperature rise under 1.5C, describing how counties can reach this temperature target and the consequences if this target is not met. ( McGrath, 2021).

In the article, “Extreme weather renews focus on climate change as scientists update forecasts”, Corinne Le Qure, a climate scientist at the University of East Anglia, says, “Global warming was well projected, but now you see it with your own eyes.”

Climate scientist Michael Mann of Pennsylvania State University, commenting on the recent series of extreme events, says that it’s not that climate change is happening faster than expected but that the impacts are greater than they have been predicted (Januta, 2021).

What can be expected from this new report?

The IPCC’s assessment reports are usually divided into three different areas of climate change: the physical science report, the study on impacts, and mitigation. The BBC article says the IPCC will release the impacts and mitigation part of the report early next year, including the synthesis report.

A rigorous process

McGrath’s article describes the rigorous process of preparing and reviewing the report to ensure that every word is scientifically accurate.

The Summary for Policymakers is produced by 200 researchers who thoroughly review existing literature and continuously revise and redraft it to accommodate comments and discussions from fellow researchers and governments. But before it is released, every line will be scrutinised and defended by the scientist who wrote it, and the final words will be agreed upon by all members of the IPCC, consisting of the researchers, scientists, and government representatives (McGrath, 2021).

Corinne Le Quéré, from the University of East Anglia, who has been involved with two previous IPCC assessment reports, say that “Nothing gets written that is not scientifically correct. So, scientists have the right just to say this is wrong, and the documents gets strong at the end because of that process” (McGrath, 2021).

What to expect from the latest IPCC report

McGrath (2021) says that, like previous assessments, there will be a strong focus on humanity’s role in creating the climate crises and the following:

• The report will strengthen this finding despite objections from some countries.
• Due to the planet’s growing warming, the report will send a more powerful message, focusing more on present and future questions rather than on past responsibility.
• It will pay more attention to the weather and extreme events such as storms, floods, droughts, and weather events with low probability but high impact, as we have recently witnessed.
• The report will include new information on sea-level rise and the state of the Arctic and Antarctic and will assess whether governments are on track to meet their Paris Climate Agreement.

Climate models in predicting extreme events at a local scale

Januta (2021) mentions that while climate models have helped climate science have high confidence in their projections, there is still significant uncertainty about how climate change will manifest locally. Answering these questions will take many years.

The extreme temperatures caused by the heatwaves, which are above 4.6 degrees, could look like freak events using climate models. Still, these temperature spikes in some places might result from new atmospheric changes that have not yet been captured by climate models, the article says.

Climate change on Jet streams.

Warming also affects the jet streams. It can slow down parts of the northern polar jet stream, especially during summer, trapping heat under high-pressure air, as was seen in Canada in June. It can also delay storms longer in one place, resulting in severe floods. 

Ken Caldeira, an atmospheric scientist at the Carnegie Institution for Science’s Department of Global Ecology, says there is “tantalising evidence” that the warming has introduced new factors that can intensify climate change impacts, which would need further research. But whatever the findings reveal, the answer remains the same – “we need to get ourselves off of CO2 emissions as soon as is practical”, adds Caldeira (Januta, 2021).

Finally, the climate change report will be a vital reference for creating climate adaptation and mitigation plans by governments and organisations worldwide.