Launch of IPCC Working Group II Contribution to the Sixth Assessment Report: Interview with Lead Author Rupa Mukerji

The Center for Climate Impact and Action (CLIMACT) spoke with Rupa Mukerji, lead author of the newly released IPCC report and Helvetas' Director of Advisory Services. The interview below was originally published on CLIMACT's website. 

The Contribution of the IPCC Working Group II to the Sixth Assessment Report has been launched today, on 28 February 2022. As a lead author of the IPCC Working Group II, can you share with us what are the key findings of this report?

The cumulative scientific evidence is unequivocal: climate change is a threat to human wellbeing and the health of the planet and any further delay in concerted global action to address climate change will mean that we miss a brief, and rapidly closing, window of opportunity to secure a livable future for all.

While the Working Group I report released in August 2021, established that human influence on the climate system is unequivocal and that the world is on average 1.1°C warmer than pre-industrial levels, this report provides the evidence that all regions of the world, ecosystems and sectors are experiencing the impacts of climate change. Global warming of 1.1°C has already caused dangerous and widespread disruption in nature, affecting the lives of billions of people, despite efforts to adapt.

It also provides evidence that we face unavoidable climate hazards over the next two decades with global warming of 1.5°C.

There is clear evidence that climate impacts and risks are becoming increasingly complex and more difficult to manage. Multiple climate hazards and risks are occurring simultaneously, compounding overall risk, and cascading across sectors and national borders.

The 7 IPCC regions are at the centre of this assessment, thus providing regionally differentiated analysis of impacts, adaptation options, their feasibility and enabling conditions. Equity, justice, inclusion and good governance emerge as important enabling conditions for societies to define priorities, manage tradeoffs – such as between adaptation, mitigation and development needs – and respond more effectively to climate impacts.

This assessment highlights that action on adaptation has increased but progress is uneven. Current adaptation actions are unequally distributed, fragmented and often inadequate to deal with current levels of warming.

The gaps between adaptation needs and actions is widening, especially in lower income countries, affecting populations who are already vulnerable and have limited capacities. It is clear that we are not prepared for the near-term impacts of global warming.

It is also clear that while there are adaptation options in every region and sector, their effectiveness declines with increased warming. We are reaching the limits to adaptation in several systems. These limits can be ecological, physical, economic, socio-cultural or technological. Losses and damages from climate change are accumulating, especially in less developed countries with higher exposure, greater vulnerability and lower adaptive capacities.

The assessment provides robust evidence that without current adaptation actions, the adverse impacts of climate change would have been stronger.   

This report takes a more holistic approach, integrating natural, social and economic sciences and highlighting the role of social justice as well as the diverse forms of indigenous and local knowledge. Why is this important?

An integrative and holistic approach is one of the most important contributions of this report. Since the Fifth Assessment Report of the IPCC, there has been an exponential growth in adaptation literature and its meta-analysis. They highlight certain global hotspots where overlapping challenges such as high levels of poverty, weak leadership, lack of accountability and trust in government, limited access to basic services combine to heighten vulnerability, including to climate change. This is manifested for instance, in the fact that the loss of lives from floods, droughts and storms in the last decade has been 15 times higher in these hot spots than in more resilient countries. Future vulnerability will also be concentrated in places where the capacity of governments, communities and the private sector to provide basic services is constrained.

Existing inequities in societies get exacerbated with climate change, and often those who have contributed the least to climate change are first and most adversely impacted. Thus, aspects of equity, fairness and justice are at the core of how climate impacts are distributed within and across societies.

There is also evidence that poor and least developed households, communities, and countries, who are most affected and marginalised by climate change, receive relatively little financial support for adaptation.

Acceleration and sustainability of adaptation requires political commitment and actions across all levels of government. Inclusive governance that prioritises equity and justice in adaptation planning and implementation, is one of the key enabling conditions for effective adaptation.

Indigenous knowledge and local knowledge about climate change have been used as a source of evidence in several regional chapters of this report. Chapter 18, of which I am a Lead Author, provides a consolidated analysis. Indigenous knowledge refers to the understandings, skills and philosophies developed by societies with long histories of interaction with their natural surroundings while local knowledge is the understandings and skills developed by individuals and populations about the places where they live. These are therefore of vital importance for place-based adaptation but have a rather recent history of being appreciated and included in scientific assessment processes.

These knowledge systems represent a range of cultural practices, wisdom, traditions and ways of knowing the world that provide accurate and useful climate change information, observations and solutions.  For instance, the Latin America regional chapter presents cases where Indigenous knowledge systems have led to a lower incidence of wildfires. There is literature from Cusco Region of Peru, which documents how cultural values of reciprocity, collectiveness, equilibrium and solidarity have led to successful adaptation to climate change. 

Indigenous and local knowledge are also crucial as they are profound sources of ethics and wisdom. They can shape how climate change risks are understood and experienced and offer the possibility of developing climate change solutions that are grounded in place-based experiences and also lead to the development of governance systems that meet the expectations of different stakeholders.

However, working with this knowledge in an appropriate and ethically acceptable way can be challenging. For instance, questions of data ‘validity’ and the requirement to communicate such knowledge in the dominant language can lead to inaccurate portrayals of Indigenous knowledge as inferior to science. In this assessment, Indigenous knowledge and local knowledge was not subsumed or required to be validated through typical scientific means. It is recognized that such a critique of validity is inappropriate, scientifically unnecessary and can disrespect Indigenous Peoples’ own identities and histories.

What are the limits of adaptation to climate change? Have we reached them yet? 

Currently, 3.3 billion people across Central and South America, Africa, South Asia, Latin America, Small Islands Developing States and the Arctic are considered highly vulnerable to climate change.

Even temporarily exceeding 1.5°C warming for several decades will result in severe and potentially irreversible impacts. Ecosystem degradation and loss will threaten lives, livelihoods, coastal protection, cultural and spiritual values. We would see species extinctions and losses of entire ecosystems such as tropical coral reefs, coastal wetlands and mountain-tops as well as large ice mass loss in some glaciers and polar ice sheets. These outcomes would be irreversible on timescales over centuries to millennia.

We are already seeing the limits to adaptation in several regions. For example, low-lying coastal areas, where high exposure and vulnerability, combined with low financial and other capacities, are resulting in forced displaced of populations, or locking in the most vulnerable in an increasingly hazardous situation. Inequality and poverty are constraints which result in disproportionate exposure and impacts for those who are least able to cope.

At 1.5°C, adaptation limits will be reached for more ecosystems and some natural solutions may no longer work. Above 1.5°C, lack of freshwater could mean that people living in small islands and those dependent on glacier and snowmelt can no longer adapt. By 2°C it will no longer be possible to farm multiple staple crops in some current growing areas.

There is increased evidence of maladaptation – actions that have unintended side-effects, such as increased climate-related risk, or increased GHG emissions. For example, seawalls reduce impacts to people and infrastructure in the short-term but can increase exposure to climate risks in the long term as more people move in or as climate hazards modify. These defences can also fragment or destroy coastal ecosystems. Indigenous Peoples, ethnic minorities and disadvantaged groups are some of the groups most affected by maladaptation, reinforcing and entrenching existing inequalities.

Low-likelihood, high-impact outcomes i.e., potential outcomes of climate change that could have major impacts but are considered unlikely or extremely uncertain, will increase if we exceed 1.5°C warming, challenging a return to below 1.5°C. Forests, peatlands and wetlands that currently store carbon could release it through increased decomposition, tree mortality and fire, thus amplifying global warming. Similarly, rapid Antarctic ice sheet melt is irreversible and there is a higher likelihood that people and ecosystems would face intolerable risks.

Beyond 2040 the threats from climate change could be many times higher than what we experience today. Every small increase in warming beyond 1.5°C will result in escalating losses and damages.

In terms of urgency to act, what does this second report bring to the table?

Worldwide, action to achieve climate resilient and sustainable development is more urgent that previously thought.

We have a narrowing time window to reach climate targets through ambitious reductions in GHG emissions, while simultaneously dealing with climate risks, preventing biodiversity loss and improving peoples’ wellbeing, such as by reducing poverty and hunger. Such climate resilient development is already challenging at global warming levels of less than 1.5°C. The scope and options for it will become more limited by 2°C and it may not be possible in some regions and sub-regions, such as small islands, mountains and polar regions, if warming exceeds 2°C.

The report finds that about 9% of species assessed are likely to face a high risk of extinction at 1.5°C. The risk of extinction in biodiversity hotspots increases by about 10-fold as warming rises from 1.5°C to 3°C.

Regions that are highly dependent on glacier melt and snowmelt for irrigation could experience a 50% decline in water supply for agriculture and hydropower, as well as for people living in towns and cities, by the end of the century.

Climate change will increasingly undermine food security. At 2°C warming by 2050, people in sub-Saharan Africa, South Asia, Central America and Small Island States are likely to experience food shortages, leading to malnutrition.

We could see a 16-fold increase in exposure to heatwaves at 2.5°C increase in global warming. Disease risks are projected to increase unless action is taken – for example an additional 2.25 billion people will be at risk of dengue under 2.6°C of global warming by 2080.

Mental health challenges including anxiety and stress are projected to increase, particularly for children, adolescents, the elderly and those with existing health conditions.

Globally, more than a billion people living in low-lying cities and other settlements on the coast, including on small islands, are projected to be at risk from sea level rise and other climate hazards by 2050. Enhanced risk of disruption to global, regional and local supply chains, through impacts on key infrastructure such as ports and transport systems, will also have development implications.

There are also potentially competing priorities such as afforestation, bioenergy, carbon capture and storage and hydropower which can harm ecosystems, reduce biodiversity and impact food and water security. These different objectives require careful balancing through effective consultation and participatory  decision-making.

The choices we make in the next decade will determine our future. Rapidly scaled-up investment, with increased international co-operation and financial assistance, would facilitate climate resilient development.

What is the best case scenario, the next steps and how would a sustainable future look like to you?

There are feasible adaptation options for every region and sector, but their effectiveness declines with increased warming. Nature offers significant untapped potential, not only to reduce climate risks, and deal with the causes of climate change, but also to improve peoples’ lives and livelihoods.

There is increasing evidence that risks to people can be reduced and biodiversity improved in many ways. Conservation measures to protect and restore natural forests, planting a range of native species, managing pests and diseases and reducing wildfire risks can build climate resilience. Informed and empowered participation of Indigenous Peoples and local communities is key.

However, it is also a fact that adaptation cannot prevent all losses and damages, even with effective adaptation and before reaching limits.

Most action to date has occurred around water-related hazard. Combinations of actions such as early warning systems have reduced loss of life. Letting nature take its course – making space for water, land-use change, and planned relocation are all promising options. In agriculture, irrigation can be effective while guarding against adverse outcomes such as depletion of groundwater. The effectiveness of most water-related adaptation declines with increasing warming.

Food security and nutrition, health and wellbeing, livelihoods and biodiversity can all be enhanced by making the food system more resilient, for example, through adopting stress-tolerant crops and livestock, diversification on farms and working with nature for pest control, pollination, storing carbon and buffering extreme temperatures. Demand side issues such as changes in diets, can reduce competition for land and water.

Urban agriculture, river restoration and other ecosystem-based adaptation are also being seen and are reasons for hope.

Adaptation in cities and other urban areas where most of the world’s population lives will depend largely on the resilience of natural, social and physical infrastructure.

For the 3.4 billion people living in rural areas around the world, resilience in the face of climate change can be improved by providing critical basic infrastructure including roads, reliable energy and safe water, improved food security and more reliable supply chains. They offer development dividends including better access to education and poverty alleviation. Strengthening health systems can reduce the impacts of infectious diseases, heat stress and other climate-related risks, especially in combination with other measures.

Feasible adaptation options in the energy sector include disaster-proofing energy plants and other critical infrastructure, ensuring market resilience and using diverse energy sources.

Nature is our key ally, protecting and restoring ecosystems, increasing the connectivity between protected areas to allow species to move to new ecologically appropriate locations and creating refuges where vulnerable species can survive locally can all help ecosystems to adapt to unavoidable change and reduce biodiversity loss. Coastal wetlands can protect against coastal erosion and flooding associated with storms and sea level rise.

Adequate finance is essential for nature conservation, restoration and protection required to accelerate progress towards sustainable development.

At present, globally, less than 15% of land, 21% of freshwater systems and 8% of the oceans are protected, often with insufficient stewardship to prevent damage or increase resilience against climate change.

Effective conservation of approximately 30-50% of land, freshwater systems and oceans will help ensure a stable planet by safeguarding nature and, at the same time, securing ecosystems services of water, food, for livelihoods, disaster risk reduction and improved health and wellbeing.