What’s new in IPCC AR6 WG II?

Last year on August  6th, the first part of a significant document in the Climate Change debate was released: The sixth assessment report (AR6) of Work Group I (WGI)  by the Intergovernmental Panel on Climate Change (IPCC). The IPCC sets the standards in the climate debate by providing scientific knowledge about it.

A brief summary of the work by the IPCC would say that volunteer experts working for the IPCC, founded in 1988 by the World Meteorological Organization (WMO) and the UN Environmental Project, produce a scientific review report, which gives a concise, state of the art picture about climate change by looking into the scientific literature. 

The assessment reports’ main goal is to provide policymakers with the basis for educated and coherent decisions. Throughout the years, the IPCC found stronger and more concerned words about the catastrophe we manoeuvre ourselves into.  

The assessment report is split into three parts. WGI deals with the physical science basis of climate change; it does so by describing what climate is and how humans alter it. Being released on Monday, WGII focuses on the impacts, adaptation, and vulnerabilities induced by climate change. Lastly, WGIII will deal with our mitigation options to climate change.

Last June, the unfinished report of WGII was leaked to AFP. The IPCC itself did not comment on the events, stating that “[t]hi is out of respect for the authors and to give them the time and space to finish writing before making the work public”. While it is not clear why it has been leaked, the spreading of the findings before COP26 in Glasgow could have been one reason. 

As of Monday, 2022.02.28, the  AR6 WGII is officially released, and the statements give little hope for the future beyond 2040. The current global mean temperature rise of 1.1 °C already accounts for losses that are bigger in magnitude and extend as anticipated in previous reports while affecting all parts of daily life. Some of these impacts are already irreversible, such as species loss. 

According to the report, degradation and destruction of ecosystems increased the vulnerability of human society. This effect has been accelerated as interconnections between systems lead to cascading, irreversible effects across systems. This means that a simple reduction of temperature will not restore the original state.

Yet, the reports clearly state that  “depending on the magnitude and duration of overshoot [the period exceeding 1.5 °C, editor’s notes], some impacts will cause release of additional greenhouse gases and some will be irreversible […] a return to a given global warming level or below would be more challenging.” The limitation to 1.5°C temperature rise reduces these negative impacts substantially. 

Risks increase across sectors and regions, the report, therefore, advocates for integrated adaptation strategies leading to effective climate-resilient development. Meanwhile, the window for adaptation is narrowing rapidly as hard limits of adaptation, such as ecosystem collapse or water stress, are approached. 

The report criticises the current short-sighted adaptation strategies and further emphasises the importance of long-term, integrated and flexible planning in combination with accelerated implementation. 

Compared to AR5, published in 2014, the new report made clear that adaptation costs have already increased, and coherent policy can only develop when enforced by an active and educated civil society. 

A new focus is further set on the integration of different perceptions, as “evidence shows that […] link[ing] scientific, Indigenous, local, practitioner and other forms of knowledge, […] are more effective and sustainable because they are locally appropriate and lead to more legitimate, relevant and effective actions.”

In a world where we have to expect 5°C of warming by the end of the century, there is no more time for delay, which again is expressed in the last paragraph in the reports summary for policymakers (SPM): 

“The cumulative scientific evidence is unequivocal: Climate change is a threat to human well-being and planetary health. Any further delay in concerted anticipatory global action on adaptation and mitigation will miss a brief and rapidly closing window of opportunity to secure a liveable and sustainable future for all.”