Editing IPCC:AR6/WGII/Chapter-16 (section)

=== 16.1.4 Drivers of Exposure and Vulnerability ===

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Climate-related impacts, risks and responses all take place against a backdrop of trends in exposure and vulnerability driven by demographics, socioeconomic development (including inequalities) and ecosystem degradation. Other global trends that are shaping climate risks include technological innovation, shifts in global power relations, and resource scarcity ( [[#Retief--2016|Retief et al., 2016]] ). Note that these global trends may ''increase'' but also ''reduce'' exposure and/or vulnerability, for instance when growing incomes, savings and social protection systems increase resilience in the face of shocks and stresses. Drivers and future trends in vulnerability and exposure—next to climate-induced changes in natural hazards—therefore need to be considered in comprehensive risk assessments and eventually adaptation solutions, but empirical research suggests that they remain to be underemphasised in current national adaptation planning ( [[#Garschagen--2021a|Garschagen et al., 2021a]] ).

While these risk drivers are often listed separately, they are often closely interconnected, including between human and ecological systems, and increasingly also through climate risks and responses (e.g., [[#Simpson--2021|Simpson et al., 2021]] ). Climate impacts increasingly affect these drivers, and may compete with financial resources that could otherwise be applied for development, mitigation, adaptation and resilience building, also affecting inequalities (e.g., [[#Taconet--2020|Taconet et al., 2020]] ).

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==== 16.1.4.1 Demographics ====

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Population growth (or decline) can result in increasing (or decreasing) pressure on natural resources (e.g., soils, water and fish stocks) ( [[#IPBES--2019|IPBES, 2019]] ), and can result in the expansion of densely populated areas ( [[#Cardona--2012|Cardona et al., 2012]] ; [[#Day--2016|Day et al., 2016]] ). The majority of the population in the coming decades will be in urban areas. While urbanisation can have many benefits that reduce vulnerability, such as employment opportunities and increased income, better access to healthcare and education, and improved infrastructure, unsustainable urbanisation patterns can create challenges for resource availability, exacerbate pollution levels ( [[#Rode--2015|Rode et al., 2015]] ) and increase exposure to some risks. For example, ~10% of the global population live in low-elevation coastal zones (in 2000; areas &lt;10 m of elevation) ( [[#McGranahan--2007|McGranahan et al., 2007]] ; [[#Neumann--2015|Neumann et al., 2015]] ), which is expected to increase by 5% to 13.6% by 2100 depending on the population scenario ( [[#Neumann--2015|Neumann et al., 2015]] ; [[#Jones--2016|Jones and O’Neill, 2016]] ). Building assets and infrastructure in naturally risk-prone areas are also projected to increase ( [[#Magnan--2019|Magnan et al., 2019]] ), which may also lead to environmental degradation that can further aggravate risk, such as destruction of wetlands that buffer against floods ( [[#Schuerch--2018|Schuerch et al., 2018]] ; [[#Oppenheimer--2019|Oppenheimer et al., 2019]] ). Demographic trends, coupled with changes in income, can also result in increasing demands for land, food, water and energy, and therefore in major changes in land use and cover change (Arneth, 2019). The observed and projected population decline in some rural areas also has implications for vulnerability and exposure. In addition, demographic changes such as ageing may increase vulnerability to some climate hazards, including heat stress ( [[#Byers--2018|Byers et al., 2018]] ; [[#Rohat--2019a|Rohat et al., 2019a]] ; [[#Rohat--2019b|Rohat et al., 2019b]] ).

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==== 16.1.4.2 Biodiversity and Ecosystems ====

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Rapidly accelerating trends in human impacts on global ecosystems and biodiversity, especially in the past five decades, have resulted in precipitous declines in the numbers of many wild species on land and in the ocean, transformation of the terrestrial land surface for agricultural production, and the pervasive spread of alien and invasive species ( [[#IPBES--2019|IPBES, 2019]] ). As a result, the capacity of ecosystems to support human society is thought to be coming under threat. For instance, the fraction of all primary production being appropriated for human use has doubled over the course of the 20th century (to about 25% in 2005), although it has grown at a slower rate than human population ( [[#Krausmann--2013|Krausmann et al., 2013]] ). Future projections significantly depend on bioenergy production, signalling one of the feedbacks between responses to climate change and climate risks.

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==== 16.1.4.3 Poverty Trends and Socioeconomic Inequalities within and across Societies ====

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Poverty contributes to exposure and vulnerability by limiting access of individuals, households and communities to economic resources and restraining adaptive capacities (e.g., for food and energy supply, or for financing adaptation responses) ( [[#Hallegatte--2017|Hallegatte and Rozenberg, 2017]] ). Over the past decades, until the COVID-19 pandemic, global poverty rates have declined rapidly. Between 1981 and 2015, the share of global population living in extreme poverty (under the international poverty line of USD 1.90 d −1 ) declined from 42% to 10%, leaving 736 million people in extreme poverty, concentrated in South Asia and Sub-Saharan Africa (World Bank, 2018). This general reduction in poverty across the world is accompanied by a decrease in vulnerability to many types of climate change impacts ( ''medium confidence'' ). However, the COVID-19 pandemic has significantly increased extreme poverty by about 100 million people in 2020, with disproportionate economic impacts on the poorest, most fragile and smaller countries ( [[#World%20Bank--2021|World Bank, 2021]] ) and significant implications for vulnerability to climate change (see also Cross-Chapter Box COVID in Chapter 7).

The majority of the population in poverty are smallholder farmers and pastoralists, whose livelihoods critically depend on climate-sensitive natural ecosystems, such as through semi-subsistence agriculture where food consumption is primarily dependent on households’ own food production ( [[#Mbow--2019|Mbow et al., 2019]] ). A significant share of this population is affected by armed conflict, which deters economic development and growth and increases local dependence on subsistence agriculture ( [[#Serneels--2015|Serneels and Verpoorten, 2015]] ; [[#Braithwaite--2016|Braithwaite et al., 2016]] ; [[#Tollefsen--2017|Tollefsen, 2017]] ), and aggravating humanitarian challenges (e.g., [[#ICRC--2020|ICRC, 2020]] ). Extreme weather events, particularly droughts, can result in poverty traps keeping people poor or making them poorer, resulting in widening inequalities within and across countries.

Climate risks are also strongly related to other inequalities, often but not always intersecting with poverty. AR5 found with ''very high confidence'' that differences in vulnerability and exposure arise from multi-dimensional inequalities, often produced by uneven development processes. These inequalities relate to geographic location, as well as economic, political and socio-cultural aspects, such as wealth, education, race/ethnicity, religion, gender, age, class/caste, disability and health status ( [[#Oppenheimer--2014|Oppenheimer et al., 2014]] ). Since AR5, a number of studies have confirmed and refined this assessment, especially also regarding socioeconomic inequality and poverty ( [[#Hallegatte--2016|Hallegatte et al., 2016]] ; [[#Hallegatte--2017|Hallegatte and Rozenberg, 2017]] ; [[#Pelling--2019|Pelling and Garschagen, 2019]] ; [[#Hallegatte--2020|Hallegatte et al., 2020]] ). Poor people more often live in exposed areas such as wastelands or riverbanks ( [[#Garschagen--2015|Garschagen and Romero-Lankao, 2015]] ; [[#Winsemius--2018|Winsemius et al., 2018]] ). Also, poor people lose more of their total wealth to climatic hazards, receive less post-shock support from their often-times equally poor social networks, and are often not covered by social protection schemes ( [[#Leichenko--2014|Leichenko and Silva, 2014]] ; [[#Hallegatte--2016|Hallegatte et al., 2016]] ). Countries with high inequality tend to have above-average levels of exposure and vulnerability to climate hazards ( [[#BEH%20UNU-EHS--2016|BEH UNU-EHS, 2016]] ). Many socioeconomic models used in climate research have been found to have a limited ability to capture and represent the poor at a larger scale ( [[#Rao--2019|Rao et al., 2019]] ; [[#Rufat--2019|Rufat et al., 2019]] ). However, an analysis of 92 countries found that relative income losses and other climate change impacts were disproportionately high among the poorest ( [[#Hallegatte--2017|Hallegatte and Rozenberg, 2017]] , see [[#16.2|Section 16.2.6]] ). There have also been advances in detecting and attributing the impacts of climate change and vulnerability at household scale and specifically on women’s agency and adaptive capacity ( [[#Rao--2019|Rao et al., 2019]] ). The distribution of impacts and responses (adaptation and mitigation) affects inequality, not just between countries but also within countries (e.g., [[#Tol--2020|Tol, 2020]] ) and between different people within societies. Distribution has so far largely been thought of in a geographical sense, but identifying those most at risk requires an additional focus on the social distribution of impacts, responses, and resilience, as influenced for instance by differential social protection coverage ( [[#Tenzing--2020|Tenzing, 2020]] ).

Many climate responses interact with all of these global risk drivers. Some raise additional equity concerns about marginalising those most vulnerable and exacerbating social conflicts ( [[#Oppenheimer--2019|Oppenheimer et al., 2019]] ), leading to wider questions about the governance of climate risks (and impacts) across scales. Hence, our assessment of impacts, responses and risks is complemented by the assessment of governance and the enabling environment for risk management in Chapter 17, and of climate resilient development in Chapter 18.

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