The IPCC AR6 Synthesis Report is Out

In March, the UN’s InterIntergovernmental Panel on Climate Change published the summary and final report of its sixth assessment report (AR6), the Synthesis Report.

So-called synthesis because it gathers the key findings of the past three main reports:

• Working Group I The Physical Science Basis, which covers the physical science of climate, including the observation and projections of global warming;
• Working Group II Impacts, Adaptation, and Vulnerability, reports on the impacts of climate change; and
• Working Group III Mitigation of Climate Change report assesses all aspects of mitigation, including technical feasibility, cost, and the enabling environments. These three reports were published in August 2021, February, and April 2022, respectively.

The IPCC comprises the world’s leading climate scientists and prepares a series of assessment reports and special reports at five to eight-year intervals – the time it takes to compile an assessment report – each assessment cycle comprising several reports (Working Group I, II, III, Special Reports, and a Synthesis Report).

The first Assessment report came on in 1990, and since then, it has completed the 6^th cycle, the latest of which is the 6^th Assessment Report (AR6). The following IPCC report will be due in 2030.

About the AR6 Synthesis Report.

As a recap of the main findings in the previous three main reports and special reports, there are no new developments in the synthesis report.

The primary purpose is to produce a shorter format reducing thousands of pages of science and bolstering further support for global climate action.

The report serves as scientists’ “final warning” on the climate crisis, as rising GHG emissions push the world to reach dangerous tipping points or irrevocable damage.

As the next AR is coming in 2030, the synthesis report is effectively the last IPCC report, while it is still feasible to stay within 1.5°C of global warming.

It outlines climate change’s already significant impact on the world and explains that this will only worsen. By the end of the century, extreme coastal flooding that happens 1 in 100 years is projected to occur at least every year in half of the world’s tidal gauge locations – where sea level recordings are made.

“Even in the near term, global warming is more likely than not to reach 1.5C even under the very low greenhouse gas scenario,” the report says.

Kaisa Kosonen, a climate expert at Greenpeace International, said: “This report is definitely a final warning on 1.5°C. If governments just stay on their current policies, the remaining carbon budget will be used up before the next IPCC report [due in 2030]” (Harvey, 2023).

The IPCC estimates we have about 400 billion tonnes left in the global carbon budget from the start of 2020. The amount of carbon dioxide we release annually is about 36 billion tonnes, giving us at the end of 2030 to use it all up (The global CO2, 2022).

Our temperatures have increased about 1.1°C above pre-industrial levels, but if GHG can peak soon and drastically reduce in the following years, it may still be possible to reach 1.5°C.

Hoesung Lee, the chair of the IPCC, said: “This synthesis report underscores the urgency of taking more ambitious action and shows that, if we act now, we can still secure a livable, sustainable future for all” (Harvey, 2023).

To read more, click on the button below.

FEATURED IMAGE CREDIT: AR6 Synthesis Report: Climate Change 2023