The recent publication, on 27 February 2022, of the second instalment to the Sixth Assessment Report of the UN’s Intergovernmental Panel on Climate Change (“IPCC“) did not receive the same degree of attention as the first instalment in August 2021.  The findings, and message, of the second instalment, are no less severe, or potentially consequential, however, delivering as it does, the “bleakest warning yet” of the impacts of climate change.

The first instalment, developed by the IPCC’s Working Group I, focused on the physical science basis of climate change.  The second instalment, developed by the IPCC’s Working Group II, assesses the impacts of climate change, looking at ecosystems, biodiversity and human communities at global and regional levels.

The findings of the IPCC are, of course, deeply troubling in many respects, and the implications of those findings are likely to be extensive.  One area in which those implications are likely to be felt is that of climate litigation.  As explored in our previous article, the science based findings of the IPCC have played a role in affirming international legal standards on climate change and establishing the link between emissions and climate change, thereby – in some respects – strengthening the cases of climate litigants who may previously have encountered difficulties in establishing causation.  The ever-increasing urgency of the climate crisis, and the willingness – and ability – of stakeholders to use litigation to compel action to address that crisis, will continue to be features of the landscape as attention focuses on the IPCC’s findings.

Key findings of the IPCC’s Working Group II

Working Group II’s contribution to the IPCC’s Sixth Assessment Report reinforces the findings of Working Group I: for example, Working Group II concludes that it is “unequivocal that human influence has warmed the atmosphere, ocean and land”; further, climate change has caused “substantial damages and increasingly irreversible losses, in terrestrial, freshwater and coastal and open ocean marine ecosystems”. 

Moreover, Working Group II produces further science-based evidence that climate change is linked to adverse impacts on human rights and human health: increasing weather and climate extreme events have exposed millions of people to acute food insecurity and reduced water security, and lead to displacement and involuntary migration.  Further, Working Group II have “high confidence” that climate change and related extreme events will “significantly increase ill health and premature deaths” in the future.

Working Group II also link climate change to economic damages, including with respect to “livelihoods and key infrastructure”, noting further that “economic damages from climate change have been detected in climate-exposed sectors, with regional effects to agriculture, forestry, fishery, energy, and tourism”.  Some extreme weather events, such as tropical cyclones, “have reduced economic growth in the short-term”.  

As causal links between greenhouse gas emissions and climate change, and in turn between climate change and specific loss and damage, continue to be compellingly established, it is likely that litigants will continue to target national governments and private organisations, deploying case theories and evidence that may not previously have been available.  Governments, corporates and financial institutions – and those who run them – will need to take heed of the findings of IPCC’s Working Group II, as well as the forthcoming two further instalments.  The third instalment, anticipated in the near future, will address “mitigation”; what steps can governments (principally) take to reduce GHG emissions?  Significant behavioural change will likely be deemed essential.

The immediacy of the IPCC’s findings is stark, and stakeholder litigation seeking not only compensatory redress, but also to force behavioural change, is likely to grow.