IPCC Working Group II Report: Key Points

On February 28, the new report from IPCC Working Group II (IPCC — Intergovernmental Panel on Climate Change). Following the report by Working Group I published last August, which provided a synthesis of knowledge on past, present, and future climates, This new report examines the impacts of climate change, as well as issues related to adaptation and vulnerability.

The report confirms that the impacts of climate change are accelerating, noting that there are limits to the adaptive capacity of ecosystems and human societies. It also differs from previous versions by placing greater emphasis on issues of climate justice, highlighting the importance of social, economic, and historical factors in shaping vulnerability.

Here we offer you a Summary of the report's key points.

Preamble: What is the IPCC?

"The Intergovernmental Panel on Climate Change (IPCC) was established in 1988 to provide detailed assessments of the state of scientific, technical, and socioeconomic knowledge regarding climate change, its causes, its potential impacts, and mitigation strategies.”

The IPCC does not, therefore, conduct new research; rather, it takes stock of the current state of knowledge based on a critical assessment of evidence drawn from scientific publications.

These assessments are provided to governments to help them develop policies and set guidelines, and serve as a basis for work during COP (Conference of the Parties) negotiations.

It consists of three working groups:

• Group I studies the physical foundations of climate and analyzes past, present, and future climates. It develops various possible scenarios based on humanity’s greenhouse gas emissions.
• Group II is working on the vulnerability of human societies, ecosystems, and socioeconomic systems to climate drift, the consequences of climate change, and adaptation options.
• Group III studies climate change mitigation, the evaluation of methods for reducing greenhouse gas emissions, and the removal of greenhouse gases from the atmosphere.

The Working Group II Report of the IPCC's Sixth Assessment Report

The Working Group II report is thus the second part of the IPCC’s Sixth Assessment Report. The Working Group III report is scheduled for March 2022, and the Working Group I report was published in August 2021.

This report is the result of an analysis of 34,000 scientific publications by 270 authors, who reviewed more than 62,418 comments.

All documents related to Group II's report ""Climate Change 2022: Impacts, Adaptation, and Vulnerability" are available here: https://www.ipcc.ch/report/sixth-assessment-report-working-group-ii/

What are the key takeaways from this report?

In this new report, the IPCC authors examined the impacts of climate change, the vulnerability of ecosystems and human societies, their capacity to adapt, and the conditions necessary for building resilient societies.

Since the AR5 report, published in 2014, our understanding of the impacts and risks caused by climate change has grown: today, the IPCC estimates that 3.3 to 3.6 billion people live in conditions of high vulnerability to climate change.

Right from the first few paragraphs, the authors also point out that:

• Climate change—and in particular extreme events, which are becoming more intense and frequent—has had widespread adverse effects on ecosystems and human societies, far exceeding natural climate variability;
• Across all sectors and regions, the most vulnerable people and systems are disproportionately affected by climate change;
• The increase in extreme weather and climate events has already had irreversible effects on natural and human systems, which have been pushed beyond their capacity to adapt.

The following paragraphs provide a (very brief) summary of the key points to take away from each of the report’s three sections. However, we encourage you to read the entire summary if you have the time (it’s less than 40 pages); it is full of valuable insights and is available here: https://report.ipcc.ch/ar6wg2/pdf/IPCC_AR6_WGII_SummaryForPolicymakers.pdf

Impacts, observed and projected risks of climate change:

Climate change affects both ecosystems and human societies:

• The impact of climate change on ecosystems (terrestrial, freshwater, and marine) can be observed through disruptions to the structure of these environments, their composition, and the phenology of species. Through these three key parameters, biodiversity and the maintenance of ecosystem services are threatened (see Figure 1).

Figure 1 – Observed impacts of climate change on ecosystems (source: Figure SPM.2 from the IPCC Working Group II report)

This figure shows, for each major region and ecosystem type, the level of confidence regarding climate change’s role in the disruption or degradation of ecosystems. The blue circles indicate a high to very high level of confidence, the purple circles a moderate level, and so on. On a global scale, it is therefore possible to state, with the highest level of confidence, that climate change is responsible for the disruption of ecosystems in terms of structure, species distribution, and phenology.

• As far as human societies are concerned, the consequences of climate change are manifold, threatening the integrity of water resources, food production (agriculture, livestock, and fisheries), the physical and mental well-being of populations (the spread of disease, malnutrition, population displacement, etc.), as well as the resilience of cities, buildings, and infrastructure (see Figure 2).

Figure 2 - Observed impacts of climate change on human systems (source: Figure SPM.2 from the IPCC Working Group II report)

This figure shows, for each region, the level of confidence regarding the role of climate change in disrupting human systems. The blue circles indicate a high to very high level of confidence, the purple ones a moderate level, and so on. The “plus” and “minus” symbols also provide further details regarding the nature of this impact: negative only, or negative and positive depending on the context. On a global scale, it is thus possible to conclude, with a high level of confidence, that climate change is harming the physical and mental well-being of populations as well as the infrastructure on which human societies rely.

The consequences of climate change, however, vary depending on a key factor: vulnerability. Between 2010 and 2020, human mortality due to floods, droughts, and storms was 15 times higher in highly vulnerable regions than in regions with very low vulnerability.

One of the key points of the report is thus the summary of factors contributing to vulnerability to climate change:

1. The vulnerability of people, regions, or systems to climate change is determined by the interplay of: 1. Socioeconomic conditions, 2. Unsustainable use of ecosystems, and 3. Contexts of inequality and marginalization. Historical and persistent patterns of inequality, such as colonialism, are also unequivocally cited as factors contributing to vulnerability.
2. Environmental degradation increases people’s vulnerability by undermining the ability of ecosystems, societies, communities, or individuals to adapt to climate change.
3. Human societies are most vulnerable in areas where local governments, communities, and the private sector are least able to provide basic infrastructure and services

Emphasizing the urgency of taking action, the report also points out that:

• The more significant the impacts of climate change are, the more difficult they are to manage, because they can occur simultaneously, interact with one another, and thereby increase the level of risk.
• Exceeding the 1.5 °C threshold would expose many human and natural systems to serious additional risks compared to remaining below that threshold.

Adaptation measures and favorable conditions;

While the report acknowledges the progress made in adapting to climate change across all sectors, it emphasizes that these efforts are unevenly distributed, largely insufficient, and that priority is too often given to immediate actions whose short-term focus prevents the building of a resilient society!

The report also highlights two key themes:

1. Feasibility (see Figure 3): Integrated, multisectoral solutions that address social inequalities, tailor responses to climate risk, and cut across systems increase the feasibility and effectiveness of adaptation across multiple sectors.
2. The issue of adaptability: Human adaptability has limits, which may be physical, financial, or related to institutional and political governance constraints. Waiting only reduces our ability to protect ourselves and preserve ecosystems from the consequences of climate change.

However, accelerating the adaptation of human systems and ecosystems to climate change cannot be achieved without a strong commitment from institutional and political leaders and without the mobilization of adequate financial resources.

Figure 3 - Various responses and adaptation measures to address key climate risks, with varying synergies with mitigation measures (source: Figure SPM.4 of the IPCC Working Group II report)

This figure illustrates the level of feasibility and synergy with mitigation for several major climate change adaptation measures. This feasibility is assessed at the global level as well as by dimension (shown in blue): economic, technological, institutional, social, environmental, and geophysical. The diagram also offers two levels of interpretation:

1. The potential of the adaptation measure in terms of feasibility and synergy, indicated by the size of the dot (high potential: large dot; low potential: smaller dot);
2. The level of confidence in this potential, indicated by the color of the dot (blue for high confidence, purple for medium confidence, and gray for low confidence).

Climate-Resilient Development.

In this final chapter, the authors point out that resilience to climate change can only be achieved under certain conditions:

1. Prioritizing risk reduction, equity, and justice in the development choices made by governments, civil society, and the private sector;
2. Integration of decision-making processes, funding, and actions at all levels of governance and across all sectors.
3. Strengthening international cooperation and collaboration between governments and communities, civil society, educational organizations, scientific institutions, the media, investors, and businesses, as well as with traditionally marginalized groups such as women, youth, and children.

Learn More

• View the report, the Executive Summary, the Technical Summary, and the FAQ: https://www.ipcc.ch/report/sixth-assessment-report-working-group-ii/
• Bon Pote - 3.3 billion people exposed to climate change: the new IPCC report is unequivocal: https://bonpote.com/33-milliards-detres-humains-exposes-au-changement-climatique-le-nouveau-rapport-du-giec-est-sans-appel/
• Environment News - The capacity of ecosystems and human societies to adapt is dwindling, according to the latest IPCC report: https://www.actu-environnement.com/ae/news/la-marge-adaptation-se-reduit-selon-rapport-giec-39177.php4