The second chapter of the IPCC’s sixth report on impacts, adaptation, and vulnerability to climate change was released on February 28. The previous chapter, which covers the latest scientific evidence on climate change. The report follows a first part on climate science released in August 2021 and had reaffirmed the unequivocal human influence on climate, reporting an average temperature increase of 1.09°C compared to the pre-industrial era. At the opening of the online event a heartfelt plea from Antonio Guterres, Secretary-General of the United Nations: “[…] of the many reports I have read in my career none like this one is an atlas of human suffering, an index of the failures of climate leadership. Already today half of the human population lives in areas endangered by the climate crisis. Many ecosystems are already at a point of no return. The Glasgow effort is not enough, people everywhere are waiting and angry, as I am.”
Like its predecessor, this chapter was built on the basis of numerous papers, more than 34,000, and vetted by more than 60,000 review comments, from 270 scientists from 67 countries.
The scientific evidence is unequivocal: climate change is a danger to human life and the health of the planet. Any further delay on action will eventually close the window of opportunity we have to secure a liveable future.
This report’s chapter focuses on the impacts of the climate crisis on ecosystems, biodiversity, then (and for the first time strongly) on human societies, economy, infrastructure: sectors that appear connected to each other as never before. A panoramic global vision is flanked and explored in detail through specific in-depth analysis by geographical regions. The most vulnerable areas are confirmed as Africa, South Asia, Island States, Central and South America, where live between 3.3 and 3.6 billion people. A large section is also dedicated to Europe and the Mediterranean.
The president of the World Meteorological Organization, Petteri Taalas, reiterated once again how extreme weather events will be increasingly intense and frequent. Catastrophic events would occur even limiting warming to +1.5°C. To date, the increase in temperature compared to the pre-industrial period has already reached +1.1 ° C causing, despite attempts to adapt, extensive damage to natural environments and human societies especially in cities where more than half of the world’s population resides, and where heat waves are intensified by various factors including smog.
As pointed out by Hoesung Lee, IPCC Chair, adaptation is a key solution to cope with climate change. One can’t help but note that action on adaptation has increased internationally, eventhought progress is uneven and not moving fast enough. The gap between the adaptations put in place and those needed is widening and presents constraints, including financial ones: current flows are insufficient to implement plans. Last but not least, the misdirection of resources on adaptation is already increasing the gap between countries with average vulnerability and countries with extreme vulnerability, exacerbating existing inequalities in a downward spiral that must be attacked with decision.
What is needed to accelerate adaptation would be political commitment at all levels of government, a clear institutional framework and goals (with priorities that define responsibilities), advanced knowledge of impacts, and continuous monitoring and assessment of risks.
Today more than ever we are aware that climate change has multiple consequences: on the state of ecosystems and on that of human societies. For example, a heat wave involves immediate risks to human health, but will have long-term repercussions on agricultural production, therefore on food security, food prices increase and consequently an economic impact on the population.
There is a risk of losing many ecosystem services, such as pollination, coastal protection, tourism, food production (fisheries), drinking water filtration, and breathable air. There is a risk of an increase in water-related diseases due to its scarcity or poor quality.
Focus on cities
Cities currently host half of the human population (a fraction that is expected to rise to ⅔ by 2050) and offer enormous multiplicative opportunities, albeit limited in time, since they can only be implemented within a certain level of warming.
Among the many viable solutions, urban agriculture and increased green space within cities will help combat heat waves and strengthen communities, along with investment in early warning systems.
Effective adaptation actions are available and can be implemented. Such as, for example, rainwater storage in agriculture, use of water saving and soil moisture conservation technologies, agricultural diversification (increasing diversity in agriculture). These are all factors that benefit the economy, ecosystems, public health, and disaster management.
Nature based solution
Inge Andersen, Executive Secretary of UNEP, from Nairobi, where the United Nations Environmental Assembly (UNEA) is underway, said that the best way to implement adaptation is to let nature do its work and use “nature-based” solutions such as growing plants in urban environments to mitigate heat. This solution is called “Agroforestry”, i.e. forests as an ally simultaneously for adaptation and mitigation, as well as functional for agriculture and food security by reducing fires and increasing climate resilience.
However, according to the IPCC report just presented, the adaptation undertaken is not enough, or rather not fast enough, especially in cities. There is a gap between the actions taken and those that would be necessary, wider in low-income populations and that will continue to grow. The risk is also the “maladaptation”: an adaptation that is not effective or that becomes effective over time, such as a physical barrier to flooding not strong enough, or an intensification of agriculture that risks depleting the soil in the long run. It is important to monitor strategies: what is effective now may not be so in 20 years.
Limits to adaptation
Many types of adaptation, including those based on nature, risk to be ineffective with a warming above +1.5°C and damages could be irreversible even if we go back below that threshold later. For this reason, strong mitigation actions are indispensable, i.e. cutting climate-altering emissions. There are also “residual risks”: the possibility that damages are irreparable despite adaptation efforts. As temperatures rise, this possibility will increase.
Future scenarios depend, in essence, on decisions that will be made today.
The major risks highlighted are increasingly frequent, intense heat waves at higher temperatures, and a general increase in water scarcity. At a warming of 2°C, glacier-supplying regions will see a decline in available drinking water for agriculture of 2% by 2050, as well as risks to food security and flooding in island and sea-level areas.
MEDITERRANEAN AND EUROPE
The region bordering the Mediterranean has warmed more than the global average (as have other landmasses) and has experienced more frequent and intense droughts.
The sea level has risen by 1.4 mm over the last century, accelerating over the last three decades, and the pH of the water has been decreasing (what is called “acidification”). Just in the Mediterranean, says the report, drought will affect between 18% and 54% of the population in the coming years in the range of average temperature growth between +1.5°C and +2°C, in a context of temperature growth in the area already higher than the global average. The 4 key risks for our region are: heat waves, decrease in water resources (especially in Southern Europe, even with moderate warming), decrease in precipitation and increase in floods (precipitation decreases but extreme ones’ increase). In practice, the greater the increase in temperature, the greater the risk.
There will also be delayed risks on cultural heritage and tourism due to the rise of the sea that will continue by inertia even if emissions are reduced to zero. Obviously it is infrastructure and communities at sea level that are primarily at risk, yet many countries that would be affected are not taking this into account.
Finally, the impacts on the biodiversity of the emerged continent are once again underlined: as warming increases, the number of species able to adapt and remain in their habitats will decrease and the efforts to protect protected areas will be in vain.
The Intergovernmental Panel on Climate Change (IPCC), is an international scientific assessment body of the United Nations that deals with the study of climate science and climate change. It is divided into 3 Working Groups: the first group (WGI) deals with the physical and scientific basis, the second (WGII) to analyse the impacts on natural environments and human societies, the third (WGIII) to summarize possible mitigation options.
The IPCC does not directly conduct research, but periodically produces reports analysing and summarizing the most recent peer reviewed scientific publications. It then resubmits its work to the international scientific community, represented for each report by a set of volunteer reviewers from different countries. Each statement in the reports is accompanied by a relative level of confidence (which can be from very low to very high) and probability (from unlikely 0-33% to virtually certain 99-100%).
Article by Anna Laura Rassu and Margherita Barbieri