What near-term climate impacts should worry us most?

Supporting the most exposed and vulnerable societies to reduce regional and global climate risks

Research paper Updated 21 October 2021 ISBN: 978 1 78413 499 0

Photo shows people lying down at a cooling station during a heatwave in Portland, Oregon, in June 2021

Dr Daniel Quiggin

Senior Research Fellow, Environment and Society Centre

Ruth Townend

Senior Research Fellow, Environment and Society Centre

Professor Tim Benton

Distinguished Fellow, Environment and Society Centre

This research paper – drawing on insights from 200 experts – highlights that, within the current decade, climate hazards are expected to have increasingly serious disruptive impacts. While many hazards may now be inevitable, action on adaptation has the potential to limit the worst expected climate impacts, at regional and global levels.

The 10 hazard-impact pathways of greatest near-term concern all relate to regions of Africa and Asia. The impacts of greatest concern – food security and migration and displacement of people – may arise from hazards such as drought, changing rainfall patterns or heatwaves. Impacts will be greatest where communities are already most vulnerable, but will also set off interacting, compounding cascades of secondary impacts that cross borders and continents.

That ‘no one is safe until everyone is safe’, often repeated during the COVID-19 pandemic, is just as critical in relation to climate hazards. Between now and 2030, support for adaptation measures to address socio-economic vulnerabilities in the most at-risk regions will be vital. Without such support, it will be impossible to avert systemic climate impact cascades that translate local hazards into impacts felt across the globe.

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03 Results and discussion

The severity of climate impacts will be amplified by existing and future socio-economic vulnerabilities in key regions. If ignored, these critical vulnerabilities will catalyse cascading impacts, creating instability across regions and globally.

3.1 Climate hazard-impact pathways

Two ‘shortlists’ of near-term climate hazard-impact pathways, one global, one continental, were drawn together through the first two rounds of the Delphi method expert engagement.

3.1.1 Global hazard-impact pathway shortlist

The global hazard-impacts pathways of greatest concern to the participants are detailed in Figures 4 and 5. The 21 individual pathways submitted at Round 1 were grouped by theme, according to the ‘impact’ element of the hazard-impact pathway. Three themes emerged: food insecurity; migration or displacement of people; and ‘other’ pathways, such as impacts on public health and damage to infrastructure that may have significant socio-economic impacts.

Figure 4. Global hazard-impact pathways shortlist, showing climate hazards and their impacts

— * Hazard-impact pathways can involve many steps, and climate hazards and impacts often overlapped in expert submissions. For example, drought can lead to food insecurity which may contribute to human displacement. Coastal flooding could lead to inundation of communities, infrastructure loss and loss of livelihoods. A public health crisis could result directly from extreme heat, or from damage to crops because of extreme heat, or could exacerbate other climate hazards and impacts such as wildfires or even pandemics. Source: Chatham House expert elicitation exercise.

Figure 5. Near-term climate hazard-impact pathways of most concern to experts engaged at Rounds 1 and 2

— Note: The highlighted pathways were put forward for further expert engagement in Round 3. Source: Chatham House expert elicitation exercise.

3.1.2 Continental hazard-impact pathway shortlist

The continental hazard-impact pathways of greatest concern are shown in Figure 6. The top 10 hazard-impact pathways identified all related to Africa (eight pathways) or Asia (two pathways). Food insecurity and migration and displacement of people were ranked highly among the continental hazard-impact pathways, as they were among the global hazard-impact pathways.

Figure 6. Continental hazard-impact pathways shortlist, showing climate hazards and their impacts, alongside the continent where impacts from the hazard are likely to be greatest

— Source: Chatham House expert elicitation exercise.

3.2 Risk amplifiers

Two categories of risk amplifiers were discussed in detail throughout the research process: earth system tipping points; and socio-economic vulnerabilities. Both have the potential to amplify risk, either by exacerbating the climate hazards, or by exacerbating the impacts from these hazards.

3.2.1 Earth system tipping points

Earth system tipping points are thresholds at which an incremental change – perhaps of a driving variable that has changed incrementally for decades with little impact – reaches a point where it pushes the earth system (or major subsystems) into a new state.28 Such tipping points can be thought of as critical thresholds that, if crossed, initiate non-linear and potentially irreversible changes (Figure 7). These changes may be sudden, but are likely to play our over long periods of time.29

Experts’ concerns about the initiation of earth system tipping points in the near term reflects growing awareness that some of these thresholds may be reached at lower temperatures than previously thought.

One of the objectives of the research that has informed this paper was to establish whether experts believe that passing critical thresholds might increase the probability or severity of specific hazard-impact pathways occurring by 2030. While there were many suggestions of tipping points that could be passed in the near-term time horizon (Figure 7), the consensus from the experts was strong around two points. The first was that whereas some tipping points may be close, or even have already been passed (such as melting of some ice sheets), it is unlikely their impacts will amplify risks appreciably before 2030.30 Second, socio-economic vulnerabilities to specific climate hazards are more likely to amplify the impacts of climate hazards within the specified timeframe (to 2030) than are earth system tipping points.

I would rather suggest to think about combined social-ecological tipping points or social tipping points within the context of climate change impacts.

Anonymized expert, Round 1

Experts’ concerns about the initiation of earth system tipping points in the near term reflects growing awareness that some of these thresholds may be reached at lower temperatures than previously thought. IPCC climate models indicate a cluster of tipping points may be initiated between 1.5°C and 2°C.31, 32 Temperature increases are already nearly 1.3°C above pre-industrial levels.33

Figure 7. Map of earth system tipping points of concern (boxed text summarizes experts’ responses)

— Source: Adapted from Carbon Brief (2020). (34 McSweeney, R. (2020), ‘Tipping Points Explainer: Nine ‘tipping points’ that could be triggered by climate change’, Carbon Brief, https://www.carbonbrief.org/explainer-nine-tipping-points-that-could-be-triggered-by-climate-change.)

3.2.2 Socio-economic vulnerabilities as near-term risk amplifiers

The experts who participated in the Round 4 workshops were nearly unanimous that increasing socio-economic vulnerabilities to specific climate hazards are more likely to amplify the impacts of climate hazards within the next decade than passing any critical threshold causing tipping points in the earth system. This assessment applies to impacts on local populations, as well as to cascading systemic risks at local, regional and global scale. As described in Box 1, the magnitude of the risk is crucially dependent on a population’s vulnerability, and so the nature and extent of the vulnerability is a factor in determining the magnitude of the risk.

Coastal flooding from storms can be taken as an example of the relative potential for amplifying impacts from socio-economic vulnerabilities to changing climate hazards. Coastal flooding from storms will be exacerbated both by climate change altering the nature of storms, and by the impact of climate change on sea level rise before 2030. In the near term, however, the amplifying impact of these changes will be relatively insignificant when compared to the amplifying impact of socio-economic changes. Exposure and socio-economic vulnerability to coastal flooding is rapidly increasing, due to changing rural-to-urban migration patterns, the growth of coastal cities, poor urban planning and infrastructure, and growing inequality. All of these factors put a greater number of people ‘in harm’s way’ of coastal flooding, and reduce available resources to deal with it, thus increasing vulnerability. These factors are likely to amplify the impacts of coastal flooding in the near term.

As part of the research that has informed this paper, we developed a thematic framework for classifying the key socio-economic vulnerabilities highlighted in relation to the most concerning hazard-impact pathways (Figure 8).

Figure 8. Classification framework for socio-economic vulnerabilities likely to amplify the impacts of climate hazard-impact pathways

In the next sections, we examine the consensus hazard-impact pathways at global and continental and regional levels in detail (Sections 3.3–3.5), before returning to an analysis of vulnerability (Section 3.6).

3.3 Specific hazard-impact pathways: food insecurity

3.3.1 Impacts on global food insecurity

At global level, climate change-related food insecurity was identified by the participating experts as being the consensus impact of greatest concern (Section 3.1.1). Food insecurity may be caused by multiple climate hazards (from extreme weather in general, or specifically by drought, change in rainfall patterns, heatwaves, flooding, or outbreaks of pests and disease); and increases in global food insecurity can arise from hazards in vulnerable countries, or hazards elsewhere, driving up world food prices, indirectly impacting vulnerable countries by changing local food availability or economic access. The greatest consensus concern over the next decade was for climate hazards arising in East Africa (including concerns about countries in the eastern Sahel and the Horn of Africa), South Asia, West Africa, Southeast Asia and Australasia (Figure 9). These five regions together accounted for 34 per cent of all the experts’ votes across hazards connected to food insecurity impacts. Concerning Africa, it was highlighted in discussions many of the votes for East and West Africa concerned the Sahel, which spans both areas.35

Greatest concern around continentally initiated climate hazards leading to global food insecurity was focused on drought within East Africa, and flooding in South and Southeast Asia. Cyclones in South and Southeast Asia were also highlighted, in addition to heatwaves, drought, flooding and changing rainfall patterns within the regions illustrated in Figure 9, and widely increased impacts from storm damage.

The potential for multiple breadbasket failure was also highlighted by the experts.36 Such a failure would occur if two or more ‘breadbasket’ regions that are significant global producers of commodity food crops suffer crop failure at the same time. The top four maize producing countries (the US, China, Brazil and Argentina) account for 87 per cent of the world’s maize exports. At present, the probability of a synchronous, greater than 10 per cent crop failure across all four countries is near zero. Under the current global emission trajectory, however, the probability of such a failure rises to around 6.1 per cent each year in the 2040s; and the probability of a synchronous failure during the decade of the 2040s is just less than 50 per cent.37, 38 Significant concern was expressed about the compounding impacts of extreme weather that would likely result in the increased probability of multiple breadbasket failure. Concurrent heatwaves in recent years further illustrate that extreme heat and flooding is increasingly co-prevalent due to planetary wave resonance.39, 40

Figure 9. Global food security hazard-impact pathways, illustrating regions where hazards may be initiated and which then go on to cause global impacts (experts’ responses)

3.3.2 Impacts on food insecurity at continental and regional level

Section 3.3.1 identified, at a global level, where experts thought climate hazards would have the greatest impacts on global food insecurity. A more granular analysis, described in this section, was enabled by asking the participating experts which climate hazards would have the biggest impact on regional food insecurity. In many of the hazard-impact pathways giving rise to food insecurity, Africa and Asia are the primary continents of concern in terms of impacts, as well as the initiating hazards (Figure 10a&b). This indicates dual concerns: that global food insecurity could stem from hazards in these regions impacting more widely through the dynamics of supply and demand (Figure 9); and that the vulnerability of local populations means that these same regions will be most impacted by food insecurity. Again, the Sahel was considered to be of particular concern in the workshops.

The greatest food security concern identified relates to East Africa, due to drought and changing rainfall patterns, coupled with heatwaves within the region, leading to crop failure. However, these climate hazards, crop failure and resulting food insecurity are likely to be felt widely across the African continent because of the fragility of the Sahel (both its socio-economic vulnerability and political instability). Regarding the climate hazards of drought and changing rainfall patterns, 26 per cent and 22 per cent of experts, respectively, identified East Africa of primary concern (Figure 10a); and 17 per cent selected West Africa regarding changing rainfall patterns. Concern regarding heatwaves was evenly spread across African regions. The food insecurity arising from these hazards (Figure 10b) is again likely to be concentrated in East Africa, with 30 per cent of experts selecting this region in relation to drought, and 21 per cent in respect of changing rainfall patterns; and 20 per cent selected West Africa in relation to changing rainfall patterns. As with the distribution of hazards across the regions of Africa, expectations of heatwaves leading to food insecurity were more evenly spread across the African continent, with North Africa being most frequently identified in this respect (16 per cent of participants).

Although not illustrated in Figure 10a&b, drought and changing rainfall patterns were also highlighted as impacting livelihoods and income throughout the African continent.

Figure 10. African regional food security hazard-impact pathways (a) initiated by hazards in various regions; (b) with impacts experienced in various regions (experts’ responses)

Experts also identified continent-specific food security concerns in relation to Asia.41 When asked to identify the regions of greatest concern for occurrence of hazard-impact pathways to occur, 42 per cent opted for South Asia as the region where drought leading to food insecurity is likely to occur; while 26 per cent identified Asia as a whole as being of concern regarding this pathway. When asked to identify specific regions in which drought-driven impacts of food insecurity in Asia are mostly likely to be felt, 46 selected South Asia, and 14 per cent Central Asia.

The experts’ workshop discussion also identified the risks to African and Asian food security arising from hazards elsewhere. As illustrated by the food price spikes in 2007–08 and 2010–11, both triggered by impactful weather (in Australia and Eastern Europe respectively), panic buying on global markets in anticipation of a shortfall in supply, coupled with the imposition of export bans, led to significant spillover effects on markets globally (extending to unaffected grains). This spillover contributed to local price rises, shortages of food aid, significant destabilization of local economies, and mass protests and rioting stemming from food-price inflation (Box 2).

Box 2. Case study: From national food insecurity to regional security concerns, and the role of global markets*

Food security in East Africa and the Sahel is intimately tied to imports from global and regional food markets, and hence global and regional food availability and prices. Table 1 lists the cereals import dependencies of East African and Sahel region countries. Over 50 per cent of cereals consumed in many of these countries are imported. In aggregate, across all the countries listed in Table 1, 23 per cent of their cereals were imported. These import dependencies demonstrate the reliance of these regions on global markets to maintain food security.

Table 1. Cereals import dependencies of East African and Sahel countries (five-year import average, expressed as percentage of 2020/21 food use)

Country	Five-year average imports as % 2020/21 food use
Burkina Faso	16%
Burundi	40%
Cameroon	31%
Chad	8%
Comoros	97%
Djibouti	97%
Ethiopia	8%
Eritrea	74%
Gambia	75%
Guinea	32%
Kenya	46%
Madagascar	21%
Malawi	8%
Mali	10%
Mauritania	76%
Mauritius	177%
Mozambique	39%
Niger	11%
Nigeria	29%
Rwanda	37%
Senegal	55%
Seychelles	107%
Somalia	81%
Tanzania	12%
Uganda	15%
Zambia	3%
Zimbabwe	35%
Average total	23%

Source: FAO (2021), Cereal supply and demand balances for sub-Saharan African countries.42

Experts expressed concerns about the compounding risks of multiple and synchronous breadbasket failures, as highlighted in Section 3.3.1, and it is clear that this is an increasingly near-term threat.

The global food crisis of 2007–08 led to a doubling of global food prices, food insecurity for importing countries, social unrest, and mass protests in at least 13 countries, including Cameroon, Egypt, Indonesia, Mexico, Morocco, Nepal, Peru, Senegal and Yemen.43, 44 The severe global food price inflation in both 2007–08 and 2010–11 arose in part from climate impacts (Australian drought, and Eastern European crop failures). These impacts interacted with other factors (low food stock transparency, depleted grain stores, and biofuel policy diverting grain to ethanol production), leading to runs on grain markets and to the implementation of export bans by some countries, further amplifying food price increases.

Looking in more detail at the 2010–11 food price spike,45 the primary trigger was exceptional summer heat in Eastern Europe, including Ukraine and western Russia,46, 47 particularly the severity and duration of extreme heat in Russia. Wheat yields fell by around one third.48, 49 At the same time, unprecedented rainfall and resulting flooding of the Indus river in Pakistan in 2010 affected the lives and livelihoods of 20 million people. Evidence suggests that these events were linked, and more likely due to climate change.50 To maintain local food supplies, Russia imposed an export ban. Uncoordinated responses from other countries, driven by internal politics and national self-interest,51 led to rapid price inflation on global markets.52 Both panic buying and speculation contributed to the food price increases.53

In developing countries, low-income group responses included reducing (by necessity) food intake and expenditure, as well as participating in demonstrations. As citizens often identified the causes of food price inflation and shortages as attributable to politicians and big business, and their disregard for the needs of the poor,54 food-related civil protests and unrest were sparked across multiple countries.55 Many countries in East Africa and the Sahel, as well as the Middle East and North Africa, experienced food riots, among them Somalia, Sudan, Tunisia, Egypt, Algeria, Oman, Iraq, Uganda and Syria.56

Not only are food riots widely understood to reduce the political stability of countries;57 instability and unrest can also spread to other countries in an affected region.58 There is some evidence that the 2010–11 food price spike was a factor that fuelled the Arab Spring uprisings, resulting in regional geopolitical instability.59 The potential consequences for future regional and international security, arising from climate-induced food insecurity as well as other climate impacts, have recently been raised as a concern by experts from multiple disciplines.60 There are fears that such impacts could lead to the rise of extremist groups, paramilitary intervention, organized violence, and conflict between people and states.61

Experts expressed concern over food security due to direct near-term climate impacts in East Africa and the Sahel, coupled with the increasing probability of climate induced synchronous multiple breadbasket failure:

First, when these vulnerable regions experience yield reductions or harvest failure due to climate, they are likely to turn increasingly to global and regional markets for imports. Second, as the probability of multiple breadbasket failure increases globally, countries in vulnerable regions are increasingly likely to experience inflated prices and lack of availability on global markets. This will exacerbate food insecurity at a time when these regions most require imports. Third, given the evidence that food crises can cause political instability, unrest and conflict, the global community should be concerned not only about increased demand on global markets during synchronous breadbasket failure periods, but also about the cascading security risks that may as a consequence arise both within and between countries.

Addressing socio-economic vulnerabilities (Table 2) provides a vital opportunity to minimize the potential for such cascading risks. Effective action could significantly decrease the likelihood that climate hazards will translate into falling crop yields, diminished food security and increased reliance on potentially strained global food markets.

For this reason, monitoring of socio-economic vulnerabilities needs to be improved, particularly in the areas of most concern – i.e. East Africa and the Sahel. Without such monitoring and subsequent action to reduce risks, the risks of near-term climate impacts will not only remain, but relentlessly increase over the next decade and beyond (Section 3.6).

* This case study also draws on Chatham House research separate to the expert elicitation described in this paper.

3.4 Specific hazard-impact pathways: migration and displacement

3.4.1 Impacts on migration and displacement at global level

At global level, climate-related migration and displacement of people was highlighted by the participating experts as the second most important near-term risk, after food insecurity, from climate change. Of all votes cast to identify critical global hazard-impact pathways, one in five was for hazard-impact pathways leading to migration and human displacement,62 while half were for pathways leading to food insecurity (Figure 4). These two hazard-impact pathways are interconnected because of the secondary impacts that can occur: food insecurity may itself drive migration, while migration can give rise to shortages of agricultural sector workers, and changes in demand for a given food supply, thus creating or exacerbating food insecurity.

Drought, sea level rise, river flooding and heatwaves were identified as climate hazards that are likely to impact global migration and displacement in the near term. Geographically, the areas of greatest concern were South, Southeast and East Asia, the Caribbean and Central America. These five regions accounted for 42 per cent of the votes across the four identified climate hazards included in pathways leading to migration and displacement. (Regions of Africa were highlighted as being of concern within the category of continental – rather than global – migration and displacement.)

There is wide variation in the models of future sea level rise, depending on emissions scenarios and how these feed into ice melt (and the potential for tipping points to accelerate ice mass loss). There is therefore potential for sea level rise to accelerate in a non-linear manner.63 Experts’ views notably varied concerning when the major impacts of sea level rise are likely to occur. One expert considered that it is ‘extremely unlikely non-linear sea level rise will occur within [the] 2030 time horizon’, while another commented that ‘flooding will be worsened by sudden increases in sea level’. Despite this, when given the option to downvote specific hazard-impact pathways within Round 2, sea level rise remained within the pathways of near-term concern. This is perhaps because sea level rise coupled with more frequent and lower-pressure storms (which can raise local sea level by a metre, plus intensifying wind effects to create storm surges) can increase flood risks markedly, and are factors already linked with migration and displacement.64 A 1 metre rise in relative sea-level increases the probability of current 100-year flood events by around 40 times in Shanghai, around 200 times in New York, and around 1,000 times in Kolkata.65

Across the world, some 230 million people are living on land less than 1 metre above current high tide lines.66 The long-term central estimate of committed sea level rise is around 12 metres, if average global temperatures are held at 2°C relative to pre-industrial levels. However, this could happen over a period of 500 years or 10,000 years: the timeframes are extremely uncertain.67

Figure 11. Global migration/displacement, initiated by hazards arising in regions (experts’ responses)

3.4.2 Impacts on migration and displacement at continental and regional level

Independent of migration and displacement concerns at the global level, drought and crop failure is likely to lead to migration and displacement within and out of Africa. East Africa was identified by 25 per cent of votes in relation to drought, and 30 per cent concerning crop failure, as causes of outbound migration (Figure 12a). The experts identified Southern Europe as the principal long-term destination for people displaced by drought and crop failure in Africa, with 34 per cent and 28 per cent of votes, respectively, assigned to this region in relation to these pathways (Figure 12b).

One expert explained the sensitivity of drought and crop failure in East Africa to changing rainfall patterns:

[The] inherent variability of the East African climate combined with the highly varied terrain and local climate heterogeneity means precipitation deviations from norms is quite high relative to other African regions.

Anonymized expert, Round 3

Figure 12. Regions of concern with regard to impacts of (a) outbound and (b) inbound migration and displacement of people due to hazards of drought and crop failure within Africa (experts’ responses)

Box 3. Case study: Migration and the cascading risk of political instability*

‘Climate refugees’ already account for more than a half of all migrants.68, 69 While it remains challenging to disentangle the factors that result in migration and displacement, the evidence that climate change is a contributing factor is mounting. Globally, every year since 2008, extreme weather (extreme heat, drought, floods, storms and wildfires) has resulted in an average of 21.8 million people being internally displaced.70 Climate-induced food insecurity is also itself a driver of migration and displacement of people, alongside direct impacts from climate hazards that contribute to migration, such as droughts and flooding.

The majority of displacements of people are local – such as rural to urban, or away from the coast – and often temporary. However, climate change is increasingly resulting in long-term population movements, such as the movement of people working with grazing herds who have then moved into traditional pastoral land in the Sahel. Climate change can also lead to longer-term erosion of living conditions, and this can eventually trigger significant outward migration. For instance, as discussed in Box 2, there is evidence that the food price spike in 2010–11, first arising from droughts in Eastern Europe, was a significant factor in the regional geopolitical destabilization in the Middle East and North Africa that in turn became a factor driving migration out of North Africa into Europe. Some 13.4 million people in the Sahel were reported in 2020 as being affected by drought and in need of humanitarian assistance.71 In 2015, as the number of refugees and migrants entering Europe, having fled conflict in the Middle East and Africa, reached its highest point, at more than 1 million,72 an equivalent number of people – some 1.1 million – were internally displaced by extreme weather events in sub-Saharan Africa alone.73 In 2020 some 4.3 million people in sub-Saharan Africa were internally displaced because of extreme weather.74

Beyond the direct effects on the individuals leaving their homes, displacement and migration also have broader impacts on the outbound and inbound regions. Outbound regions are likely to suffer impacts such as the abandonment of land, declining agricultural yields, loss of skills, reduced contributions to GDP and a decline in socio-economic conditions,75 to name only a few. The impacts for inbound regions depend on the capacity of the region to absorb and support incoming migrants, and the attitudes of the local population towards them. Impacts may include increased pressure on public services, infrastructure and resources such as drinking water, as well as rising societal tensions.76 Evidence that political instability leads to reduced economic growth is broadly uncontested.77 Some also point to evidence that higher immigration rates may increase political instability.78

What is often termed the European ‘migrant crisis’ of 2015 offers a lens through which to examine the inbound migration pressures that climate change may create,79 as well as the potential for cascading impacts of political instability. During this period, EU member states engaged in dialogues with the European Commission on inbound migration. Yet as the ‘crisis’ progressed, divisions between member states and the Commission emerged, as a result of which the EU failed to agree a common migration and asylum policy. This impasse was partially due to member states wanting to protect their own interests above those of others. One example of this is member states’ lowering their own official development assistance (ODA) allocations, on the basis that costs for hosting refugees are taken from these budgets,80 a development that the then president of the European Commission, Jean-Claude Juncker, described as ‘scandalous’.81

During the ‘crisis’, countries such as Slovakia and Hungary became increasingly reluctant to support or even recognize the EU-wide quota system for refugees and asylum seekers, fearing large influxes of immigrants would disrupt the stability of their labour markets. Some member states implemented additional border controls.82 Such responses should not only be viewed as a direct reaction to inbound migration; they were also a reaction to domestic popular opinion about migration. Many have argued that societal perceptions that a government is unable to secure its borders can lead societies to seek new forms of political power, out of a sense of necessity.83 Given this, there is little wonder that many political commentators have connected immigration with the rise of populism and far-right political parties in Europe.84

Results from a regular survey on EU member states’ citizens’ attitudes towards migrants from poorer countries were published in 2019.85 The proportion of respondents indicating they would unconditionally reject arrivals declined from 15 per cent in 2014/15 to 10 per cent in 2016/17, with individuals who felt themselves ‘politically disempowered, financially insecure and without social support … most likely to develop extremely negative attitudes towards migrants’. The survey also found that individuals ‘who place more importance on security tend to have the most negative attitudes towards migration’.86 Overall, then, EU citizens’ attitudes towards immigration appeared to be decreasingly hostile over the survey period. However, the evidence suggested around one in 10 Europeans still believed their country should reject migrants from poorer countries outright.87

* This case study has been developed through Chatham House desk research, separate to the expert elicitation described in this paper.

3.5 Specific hazard-impact pathways not mediated through food or human displacement

The expert elicitation highlighted four further global pathways (Figure 4) and three further continental pathways (Figure 6) as of consensus near-term concern. These pathways culminate in impacts of coastal flooding, public health crises and ecosystem/species loss at global level, in conflict and loss of livelihoods or income at continental level, and in infrastructure loss and damage at both global and continental levels.

3.5.1 Hazard-impact pathways not related to food or human displacement

Global impacts from sea level rise

Coastal flooding due to sea level rise received an aggregate of 34 votes. As discussed in Section 3.4.1, climate models currently provide varying projections for the trajectory of sea level rise in future, although within the near-term time frame (i.e. to 2030) sea level rise is likely to remain incremental. Nonetheless, any sea level rise, in combination with storm surges that may become larger due to increased storm intensity, is a cause for concern. The Delphi process identified coastal flooding with the potential for global impacts originating in East Asia, Australasia and Southeast Asia (Figure 15a).

Figure 13. 2030 projected sea levels in and around Shanghai, based on a scenario of moderate cuts to pollution, and using the Leading Consensus sea level projection (IPCC 2021)

— Source: Climate Central Coastal Risk Screening tool. (88 Climate Central (2021), ‘Land projected to be below tideline in 2030’, https://coastal.climatecentral.org/map/8/121.2258/31.3724/?theme=sea_level_rise&map_type=year&basemap=roadmap&contiguous=true&elevation_model=best_available&forecast_year=2030&pathway=rcp45&percentile=p50&refresh=true&return_level=return_level_0&slr_model=kopp_2014 (accessed 30 Sept. 2021).)

For example, Figure 13 shows 2030 sea level rise and annual flood projections for Shanghai, one of the world’s most populous cities and busiest ports. Any significant event (perhaps a combination of extreme rainfall causing the Yangtze river to flood, coupled with a storm and increased coastal flooding) impacting Shanghai would interrupt the flow of goods in and out of the port, leading to globally significant disruption of supply chains.89

Global impacts from storms

Near-term global infrastructure loss and damage due to storms was also raised as a concern. Local infrastructure damage clearly undermines local societies by disrupting the flow of goods, people and/or information, as well as through the economic costs incurred. Significant infrastructural damage around key areas – such as manufacturing facilities and/or transport infrastructure – also has the potential to create cascading risks through interruption of supply chains (see Box 4). The regions where such damage may occur, particularly from storms, with associated global significance were identified as East and Southeast Asia, North and Central America, and the Caribbean (Figure 15b), together accounting for 66 per cent of votes in Round 3. It should be noted that the participating experts also identified significant concern regarding regional infrastructure loss and damage due to storms originating in and impacting South Asia (Section 3.5.2).

Box 4. Case study: Storm damage to infrastructure in Asia, impacting global supply chains*

In September 2018 Typhoon Mangkhut caused severe damage and disruption across Southeast and East Asia and beyond; its direct impacts were felt across territories including the Philippines, Malaysia, Taiwan, Hong Kong, Macau, southern China, Vietnam and Guam. In south China alone, some 2.45 million people had to be evacuated for their safety.90 Some $3.77 billion of damaged was caused, and over 130 people lost their lives.91

Attribution of extreme weather events to climate change is challenging, and tropical cyclones are no exception.92 Large fluctuations in the intensity and frequency of tropical cyclones compounds these difficulties, with studies demonstrating conflicting results.93 However, climate models indicate the most intense cyclones are likely to substantially increase in frequency with climate change, with significant (20 per cent) increases in precipitation rates within 100 km of the centre of the storm.94

Increasingly in recent years, governments and infrastructure operators have been warned about the fragility of many forms of infrastructure. The power and transport sectors are perhaps the most vulnerable,95 with both direct and indirect associated risks from climate hazards. For instance, power outages can be brought about by a power plant being flooded directly, or by the network infrastructure itself failing as power lines are brought down by high winds or flooding. This is precisely what happened during Typhoon Mangkhut in China. On the Guangdong power grid, six 10 kV towers, thousands of pylons, over 700 km of cable lines and 33 distribution transformers were damaged.96 The causes identified included soft soil due to rainfall causing cable poles to tilt and collapse, wind speeds exceeding design thresholds, and damage due to landslides.97

Not only did 13 locations experience blackouts,98 but transport was shut down across southern China,99, 100 and in Hong Kong alone more than 800 international flights were cancelled or delayed, with more than 100,000 passengers affected.101

International shipping was also impacted, with Hong Kong and Shenzhen ports closed for three days, and full operations only restored after several more days.102 Both these ports are integral to global trade and supply chains: in 2017 Hong Kong was the third largest container ship port globally, and Shenzhen the fifth largest. As illustrated in Figure 14, nine of the world’s 10 biggest ports, by volume handled, are located in Southeast and East Asia.103 In total, more than 200 container ships were ‘considerably delayed’ by the impacts of Typhoon Mangkhut.104

Figure 14. The 10 largest ports globally, by volume handled (in TEUs), 2019

While not a result of a tropical storm, similar disruption to global trade was experienced during the Yangtze river flooding of 2020, caused by the highest rainfall in 60 years in the affected area.105 The authorities were forced to destroy a dam at risk of collapse,106 which disrupted cargo ships down the river and within Shanghai port.107 Critically, exports of personal protective equipment for health workers battling COVID-19 were delayed by the disruption caused by the Yangtze river flooding.108 Significant disruptions to global trade expose countries that rely on certain goods to risks; and, where goods are essential – such as food – the economically marginalized are most vulnerable to shortages.

The principal vulnerability of large global shipping ports is their coastal location, meaning options to increase resilience are limited. The UN Conference on Trade and Development (UNCTAD) has called for ‘accurate information, including climate and socio-economic data at the local level’, stating that this ‘is a pre-requisite for informed decision making and well-designed and effective adaptation response measures’.109 Compiling such information is clearly essential given that 80 per cent of global trade is ocean based,110 and as Figure 14 illustrates, there is concentration of port dependency in Southeast and East Asia, where experts predict impacts from storms will be greatest in the near term.

* This case study has been developed through Chatham House desk research, separate to the expert elicitation described in this paper.

Global impacts from heatwaves

The participating experts also identified heatwaves of global significance as a key near-term hazard. Heatwaves causing health crises – particularly through heat exposure – globally were seen as likely to occur across a fairly even spread of subcontinental regions (Figure 15c). Heatwaves leading to globally significant ecosystem, habitat and species loss (Figure 15d) were seen as most likely to originate within South America, Australasia and sub-Saharan Africa.

Figure 15. Other global hazard-impact pathways, identifying the region in which the hazard occurs (experts’ responses)

Box 5. Case study: Heatwaves and changing weather patterns leading to pests and diseases*

Emerging infectious diseases and vector-borne diseases, as well as the rise of pests, were not among the top-ranked hazard-impact pathways identified by the group of participating experts in the survey rounds. During the workshops, however, the experts did identify the need to highlight these risks to human health and food security.

Climate change disrupts ecosystems and increases the risks of diseases jumping to new hosts.111 Scientists have been warning for many years of the probability of pandemics increasing as a result of climate change.112 In 2008, a study published in the journal Nature found that over the previous decade nearly one third of emerging infectious diseases were vector-borne, with the jumps to humans corresponding to changes in the climate. For instance, insects such as infection-bearing mosquitoes follow changing geographic temperature patterns.113 In parallel research conducted at Chatham House,114 experts identified an amplifying cascade of climate risks. Changing weather patterns are likely not only to decrease crop yields and lead to the displacement of people, but also to alter ecosystems. This can in turn lead to an increased prevalence of pests disrupting crops in new areas, as well as emerging infectious and vector-borne diseases as humans and pests (and also animals) interact in new ways, compounding the impacts of food insecurity and displacement of people.

* This case study has been developed through Chatham House desk research, and an expert elicitation exercise separate to that described in this paper.

Box 6. Case study: The crucial role of vulnerable energy infrastructure during heatwaves*

One of the key considerations highlighted by the expert elicitation process described in this paper was the role of energy supply in mitigating extreme heat. There was recent clear evidence of this in the North American heat dome in July 2021, in which extreme heat triggered electricity blackouts and thus impaired the capacity for cooling through air conditioning.115 This extreme heat event also had more direct public health impacts, with one public health officer in Oregon describing conditions as ‘life-threatening heat’.116 The Guardian reported: ‘The intense and unrelenting heat is believed to have killed as many as 500 people in the province of British Columbia and contributed to the hundreds of wildfires currently burning across the province.’117

Such crises could be due to the direct impacts of heat on electricity infrastructure, and indirect impacts on infrastructure such as wildfires damaging power lines. These impacts lower energy security at times of increased reliance on air conditioning during heatwaves. For many populations across the world, lack of exposure to previous heat events may mean a lack of investment in air conditioning. A lack of economic access across the developing world means exposure to the direct impacts of heat without the possibility of cooling.

Experts also touched on the compounding impact of heatwaves occurring concurrently with around public health emergencies of international concern (such as the COVID-19 pandemic), in which vulnerable energy infrastructure could exacerbate the direct impacts of heatwaves and compound mortality. Energy supplies are both particularly vital and particularly vulnerable during heatwaves. During the COVID-19 pandemic, electricity has been vital in the operations of health services, including for the mechanical ventilation of critically ill patients.118 The context of the pandemic also created the need for special considerations when establishing cooling centres in the North American heat dome of mid-2021, to prevent exacerbating the spread of the virus.119

* This case study has been developed through Chatham House desk research, separate to the expert elicitation described in this paper.

3.5.2 Hazard-impact pathways not related to food or human displacement at continental and regional levels

Storm damage to infrastructure in Asia

While the impact of infrastructure loss and damage in Asia can have global significance due to the ability to interrupt supply chains (Section 3.5.1 and Box 4), the localized impacts of such events within the region is important: disrupting livelihoods, threatening lives and creating large-scale economic losses. As can be seen in Figure 16a&b, experts considered that Southeast and South Asia were likely to suffer near-term primary impacts from such climate hazards, with secondary impacts also concentrated in the same regions. East Asia was also flagged, but with lower concern in relation to primary impacts (Figure 16a), and slightly higher concern regarding secondary impacts (Figure 16b).

Figure 16. Regions where cyclones and typhoons are likely to suffer (a) primary and (b) secondary climate change impacts in Asia (experts’ responses)

Box 7. Case study: Storm damage to infrastructure in Asia*

In the summer months of 2021 there was significant storm damage to infrastructure in China, arising from prolonged periods of very intensive rainfall. In parts of Henan Province in China, more than an average year’s worth of rain fell in under five days, and the capital, Zhengzhou, received the equivalent of half its annual average rainfall in just six hours.120 At least 25 people were reported to have been killed in the flooding, including 12 people in Zhengzhou after passengers were trapped in rising waters of flooded underground railway tunnels.121 There was widespread further damage to infrastructure, and some 200,000 residents had to be evacuated to safety. With more than a dozen cities affected, President Xi Jinping said there had been ‘significant loss of life and damage to property’.122 Emergency measures to limit potentially devastating further damage included the forced demolition of part of the Yihetan dam at Luoyang – a city of approximately 7 million people – to prevent its collapse,123 which authorities were concerned may be imminent.124

* This case study has been developed through Chatham House desk research, separate to the expert elicitation described in this paper.

Drought leading to conflict in Africa

Climatological drought was identified by the participating experts as a potential contributor to conflict and an important near-term concern in Africa. Clearly a prime proximal route for this pathway is through drought’s impact on food and water security, as well as through consequences for human displacement. Again, East Africa was the region of greatest concern, accounting for 30 per cent of Round 3 votes (Figure 17).

Figure 17. Drought leading to conflict in Africa (experts’ responses)

3.6 Addressing socio-economic vulnerabilities is in all countries’ collective interest

Global cascading climate risks (in which a climate hazard in one place may trigger impacts that cascade and amplify across nations and borders) are increasingly of near-term concern.125, 126, 127, 128 The prevalence of such cascades, and the complexities of mapping the regional and global interdependences through which such cascades are transmitted, means one country’s vulnerability and exposure is potentially many countries’ or indeed every country’s concern. The case studies presented in Boxes 2–4 describe some of the potential risks of such cascades, and their interplay with vulnerable regions of concern.

Wealthy nations, global leaders, multilateral development finance institutions and the private sector all have a clear stake in addressing the socio-economic vulnerabilities that are likely to lead to regional or global political and security instability.

Wealthy nations, global leaders, multilateral development finance institutions and the private sector all have a clear stake in addressing the socio-economic vulnerabilities (summarized in Table 2) that are likely to lead to regional or global political and security instability (as explored in Box 3), as well as addressing the supply-chain risks inherent in the examples in Box 4. Table 2 summarizes the critical socio-economic vulnerabilities – as identified by the experts who participated in the elicitation process that has informed this paper – likely to amplify the impact of climate hazards within the three categories of hazard-impact pathways presented in the previous sections. These vulnerabilities exist at global, continental and regional levels. Regional vulnerabilities are centred around East Africa and the Sahel, as well as South Asia. Many of the socio-economic vulnerabilities that are identified within Table 2 as likely to amplify the impacts of climate hazards on food insecurity are also expected to amplify the impacts on human migration and displacement.

Table 2. Summary of socio-economic vulnerabilities (global, unless otherwise stated) likely to exacerbate near-term global and regional impacts of climate change, global and regional (italics denote direct quotes from participating experts)

As illustrated in Table 2, the participating experts highlighted several interlinked vulnerabilities that may exacerbate the impact of climate risks as concerns food security (Figure 10), with interconnections to migration and displacement, and conflict in East Africa and the Sahel. Their potential impacts have an inherent possibility of initiating cascading risks that propagate out of the region. A particularly important area where vulnerabilities can be reduced is through agricultural adaptation. On average, just 5 per cent of the cultivated area within Africa is currently irrigated, compared with an average of 21 per cent globally.129 This points to an opportunity to increase the resilience of food production. A 2019 review of National Communications130 submitted by 21 African countries to the UNFCCC identified six thematic areas and 33 categories of climate change adaptation measures within the crop sector (Table 3).131 These adaptation measures are a synthesis of measures identified by the vulnerable countries themselves, and therefore offer locally specific and relevant actions that clearly have buy-in from the administrations that will ultimately deliver them.

Implementation of such adaptation measures has, however, proved historically challenging. As one expert pointed out:

In Sudan, for example, we see through our field projects that climate adaptation of farming and grazing is possible and offer good opportunities for peacebuilding too. However, there are challenges linked to the successful implementation of these interventions, such as geographic, political, economic, social, and cultural.

Anonymized expert, Round 3

Table 3. Crop sector adaptation themes and categories, synthesized from National Communications submitted by 21 African countries to the United Nations Framework Convention on Climate Change (UNFCCC)

— Source: Muchuru and Nhamo (2019). (132 Ibid.)

Vulnerabilities beyond agricultural production also need to be addressed to reduce the likelihood of climate hazards translating into food insecurity, and migration and displacement of people. Ensuring livelihoods are diversified, levels of poverty are reduced, and skilled jobs are created will all help to tackle inequalities,133 and enable communities to continue to afford staple foods.134 This is particularly important given that nearly 80 per cent of people in East Africa rely on agriculture for their income, and the agriculture sector provides 40 per cent of the region’s GDP.135 Furthermore, ensuring that governance institutions are strengthened in the region will aid these institutions’ ability to deliver social security and welfare, increasing the region’s ability to adapt and respond to climate impacts.136 Indeed, addressing health and education provision and the ability to plan for the future, alongside tackling poverty and financial inequalities, often enhances the adaptive capacity of communities.137

Experts raised many concerns about security related to food, water and energy as well as conflict, terrorism, and societal and ethnic tensions. These issues are all complex and interact with climate change (and adaptation), and with pre-existing vulnerabilities that increase the risk of climate impacts: for example, a drought can exacerbate food insecurity, resulting in abandonment of land and human displacement, all of which can increase risks and tensions that result in more acute impacts. Conflict can also hinder climate change adaptation, as well as damaging or destroying key resources and infrastructure.138 As such, adaptation measures should, at a minimum, not increase the risk of conflict, and should if possible enhance peacebuilding. It should be recognized that efforts to combine adaptation and peacebuilding require improved governance, security and economic growth, and – crucially – the buy-in of affected communities.139

Migration and human displacement themselves cause impacts for both the places that people flee from, and the places that people flee to (Box 3). As outlined in Box 3, immigration into Europe (in which climate may have played a role) has been a factor in the political instability Europe has witnessed over the last six years. Experts who contributed to the elicitation process that has informed this paper expressed concerns over the potential for near-term climate impacts to drive further increases in migration, particularly from Africa into Southern Europe. Given this concern, as well as the fact that political instability often leads to impaired economic growth, there is a clear case for addressing the socio-economic vulnerabilities summarized in Table 2. Doing so could offer a means to prevent or minimize cascading climate risks relating to migration. Steps would include addressing the issues that currently drive migration of vulnerable populations, and more effectively integrating immigrants into new communities and countries, which may require significant strengthening of governance institutions. Governments and the international community should therefore give particular attention to:

Those vulnerabilities that translate climate hazards into food insecurity, which in turn drives migration. This involves a greater focus on climate-smart agriculture to build local resilience of food systems. As already noted, within Africa only 5 per cent of cultivated area is under irrigation, compared with the global average of 21 per cent.140 Many in-field adaptation measures already exist to improve the resilience of food production. Improving the uptake of agricultural adaptation measures appears to represent a key intervention for preventing cascades of climate impacts culminating in heightened migration.
Those vulnerabilities that translate direct climate hazards more directly into drivers of migration, such as poverty and inequality, intercommunal tensions, gender inequalities, lack of access to education, and lack of alternative livelihoods in vulnerable communities and regions.

The expert elicitation process identified the vulnerability of global supply chains to critical port infrastructure damage due to storms in Asia in the near term. The concentration of port dependency in Southeast and East Asia, and limited ability to relocate ports, constrains the range of interventions available to reduce vulnerabilities. The findings of this research support UNCTAD’s call for more accurate information on the risks and vulnerabilities to which ports are potentially exposed, as a ‘pre-requisite for informed decision making and well-designed and effective adaptation response measures’.141 International standard ISO 31000:2009 – Risk management – Principles and guidelines provided port authorities with the framework, principles and processes for managing risk.142 A range of ‘soft’ and ‘hard’ measures exist,143 including:

Creating financial instruments to support adaptation
Increasing standards of port construction to deal with higher winds
Increasing breakwater dimensions
Building new coastal defences
Raising transport levels and port elevations
Expanding dredging and nourishment programmes to handle increased quantity of sediment shifting
Improving decision support tools and information
Enhancing emergency evacuation plans

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While the tipping points may each be a threshold, the consequences for the system’s dynamics may play out over long time periods (for example, sufficiently warmed oceans will preclude any sea ice, but it may take hundreds of years for the current ice to melt and the sea level to equilibrate to new levels.

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It should be noted that the subregional breakdown (Round 3) did not include the Sahel.

These concerns were part of the long-form responses given by experts during Rounds 1 and 3, and were also raised during the workshops.

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Planetary waves result from the conservation of potential vorticity. They are influenced by the Coriolis force and pressure gradient.

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86 votes of 421. Votes are aggregate of submissions and critical votes, with ‘remove’ votes taken away from the total.

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Al Jazeera (2021), ‘Central China: 25 dead in flooded Zhengzhou metro, landslides’, 20 July 2021, https://www.aljazeera.com/news/2021/7/20/army-issues-dam-warning-deadly-storm-hits-china.

BBC News (2021), ‘China floods: 12 dead in Zhengzhou train and thousands evacuated in Henan’, 21 July 2021, https://www.bbc.co.uk/news/world-asia-china-57861067.

Associated Press via NPR (2021), ‘China Blasts Dam To Divert Massive Floods In Henan Province’, https://www.npr.org/2021/07/21/1018764692/china-blasts-dam-to-divert-massive-flooding-that-has-killed- at-least-25?t=1627381995163&t=1627990725493.

Al Jazeera, ‘Central China: 25 dead in flooded Zhengzhou metro, landslides’.

Lawrence, J. et al. (2020), ‘Cascading climate change impacts and implications’, Climate Risk Management, 29, doi:10.1016/J.CRM.2020.100234.

Challinor et al. (2018), ‘Transmission of climate risks across sectors and borders’.

Cradock-Henry, N. A. et al. (2020), ‘Elaborating a systems methodology for cascading climate change impacts and implications’, MethodsX, 7, doi:10.1016/J.MEX.2020.100893.

Hilly, G. et al. (2018), ‘Methodological framework for analysing cascading effects fromflood events: The case of Sukhumvit area, Bangkok, Thailand’, Water, 10(1), doi:10.3390/W10010081.MDPI AG.

Borderon, M. et al. (2019), ‘Migration influenced by environmental change in Africa: A systematic review of empirical evidence’, Demographic Research, 41, doi:10.4054/DEMRES.2019.41.18.

A national communication is a report that each party to the UNFCCC prepares periodically in accordance with the guidelines developed and adopted by the Conference of the Parties (COP). It is a commitment to provide to the COP: A national inventory of anthropogenic emissions; a general description of implementation steps taken or envisaged; other information considered relevant to achieving the objectives of the Convention.

Muchuru, S. and Nhamo, G. (2019), ‘A review of climate change adaptation measures in the African crop sector’, Climate and Development, 11(10): pp. 873–885, doi:10.1080/17565529.2019.1585319.

Ibid.

International Labour Office (2010), A Skilled Workforce for Strong, Sustainable and Balanced Growth, https://www.oecd.org/g20/summits/toronto/G20-Skills-Strategy.pdf.

Mensah, C. (2014), ‘The impact of livelihood diversification on food security amongst farm households in northern Ghana: a case study of Bole district’ (thesis).

Orindi, V. A. and Murray, L. A. (2005), ‘Adapting to climate change in East Africa: a strategic approach’, International Institute for Environment and Development, https://pubs.iied.org/9544iied.

IPCC: Parry, M. L, Canziani, O. F., Palutikof, J. P., van der Linden, P. J. and Hanson, C. E. (eds) (2007), Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press; Tenzing, J. D. (2020), ‘Integrating social protection and climate change adaptation: A review’, Wiley Interdisciplinary Reviews: Climate Change, 11(2), doi:10.1002/WCC.626.

Ford, J. D. et al. (2015) ‘The status of climate change adaptation in Africa and Asia’, Regional Environmental Change, 15: pp. 801–814, doi:10.1007/s10113-014-0648-2.

Price, R. (2019), ‘Climate change, vulnerability to violent extremism and conflict in Kenya’, https://assets.publishing.service.gov.uk/media/5d9b4db740f0b607f3e67941/639_Climate_Change_and_Violence_in_Kenya.pdf.

Ibid.

Borderon et al. (2019), ‘Migration influenced by environmental change in Africa’.

Asariotis et al. (2017), Port Industry Survey on Climate Change Impacts and Adaptation.

Becker, A. et al. (2017), ‘Implications of climate change for shipping: Ports and supply chains’, Marine Affairs, 9(2), doi:10.1002/wcc.508. Note that ISO 31000:2009 has since been superseded by ISO 31000:2018: see https://www.iso.org/standard/43170.html.

Becker, A. H. et al. (2013), ‘A note on climate change adaptation for seaports: a challenge for global ports, a challenge for global society’, Climatic Change, 120(4), doi:10.1007/S10584-013-0843-Z.

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What near-term climate impacts should worry us most?

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03 Results and discussion

3.1 Climate hazard-impact pathways

3.1.1 Global hazard-impact pathway shortlist

Figure 4. Global hazard-impact pathways shortlist, showing climate hazards and their impacts

Figure 4. Global hazard-impact pathways shortlist, showing climate hazards and their impacts

Figure 5. Near-term climate hazard-impact pathways of most concern to experts engaged at Rounds 1 and 2

Figure 5. Near-term climate hazard-impact pathways of most concern to experts engaged at Rounds 1 and 2

3.1.2 Continental hazard-impact pathway shortlist

Figure 6. Continental hazard-impact pathways shortlist, showing climate hazards and their impacts, alongside the continent where impacts from the hazard are likely to be greatest

Figure 6. Continental hazard-impact pathways shortlist, showing climate hazards and their impacts, alongside the continent where impacts from the hazard are likely to be greatest

3.2 Risk amplifiers

3.2.1 Earth system tipping points

Figure 7. Map of earth system tipping points of concern (boxed text summarizes experts’ responses)

Figure 7. Map of earth system tipping points of concern (boxed text summarizes experts’ responses)

3.2.2 Socio-economic vulnerabilities as near-term risk amplifiers

Figure 8. Classification framework for socio-economic vulnerabilities likely to amplify the impacts of climate hazard-impact pathways

Figure 8. Classification framework for socio-economic vulnerabilities likely to amplify the impacts of climate hazard-impact pathways

3.3 Specific hazard-impact pathways: food insecurity

3.3.1 Impacts on global food insecurity

Figure 9. Global food security hazard-impact pathways, illustrating regions where hazards may be initiated and which then go on to cause global impacts (experts’ responses)

Figure 9. Global food security hazard-impact pathways, illustrating regions where hazards may be initiated and which then go on to cause global impacts (experts’ responses)

3.3.2 Impacts on food insecurity at continental and regional level

Figure 10. African regional food security hazard-impact pathways (a) initiated by hazards in various regions; (b) with impacts experienced in various regions (experts’ responses)

Figure 10. African regional food security hazard-impact pathways (a) initiated by hazards in various regions; (b) with impacts experienced in various regions (experts’ responses)

Box 2. Case study: From national food insecurity to regional security concerns, and the role of global markets*

Table 1. Cereals import dependencies of East African and Sahel countries (five-year import average, expressed as percentage of 2020/21 food use)

3.4 Specific hazard-impact pathways: migration and displacement

3.4.1 Impacts on migration and displacement at global level

Figure 11. Global migration/displacement, initiated by hazards arising in regions (experts’ responses)

Figure 11. Global migration/displacement, initiated by hazards arising in regions (experts’ responses)

3.4.2 Impacts on migration and displacement at continental and regional level

Figure 12. Regions of concern with regard to impacts of (a) outbound and (b) inbound migration and displacement of people due to hazards of drought and crop failure within Africa (experts’ responses)

Figure 12. Regions of concern with regard to impacts of (a) outbound and (b) inbound migration and displacement of people due to hazards of drought and crop failure within Africa (experts’ responses)

Box 3. Case study: Migration and the cascading risk of political instability*

3.5 Specific hazard-impact pathways not mediated through food or human displacement

3.5.1 Hazard-impact pathways not related to food or human displacement

Global impacts from sea level rise

Figure 13. 2030 projected sea levels in and around Shanghai, based on a scenario of moderate cuts to pollution, and using the Leading Consensus sea level projection (IPCC 2021)

Figure 13. 2030 projected sea levels in and around Shanghai, based on a scenario of moderate cuts to pollution, and using the Leading Consensus sea level projection (IPCC 2021)

Global impacts from storms

Box 4. Case study: Storm damage to infrastructure in Asia, impacting global supply chains*

Figure 14. The 10 largest ports globally, by volume handled (in TEUs), 2019

Figure 14. The 10 largest ports globally, by volume handled (in TEUs), 2019

Global impacts from heatwaves

Figure 15. Other global hazard-impact pathways, identifying the region in which the hazard occurs (experts’ responses)

Figure 15. Other global hazard-impact pathways, identifying the region in which the hazard occurs (experts’ responses)

Box 5. Case study: Heatwaves and changing weather patterns leading to pests and diseases*

Box 6. Case study: The crucial role of vulnerable energy infrastructure during heatwaves*

3.5.2 Hazard-impact pathways not related to food or human displacement at continental and regional levels

Storm damage to infrastructure in Asia

Figure 16. Regions where cyclones and typhoons are likely to suffer (a) primary and (b) secondary climate change impacts in Asia (experts’ responses)

Figure 16. Regions where cyclones and typhoons are likely to suffer (a) primary and (b) secondary climate change impacts in Asia (experts’ responses)

Box 7. Case study: Storm damage to infrastructure in Asia*

Drought leading to conflict in Africa

Figure 17. Drought leading to conflict in Africa (experts’ responses)

Figure 17. Drought leading to conflict in Africa (experts’ responses)

3.6 Addressing socio-economic vulnerabilities is in all countries’ collective interest

Table 2. Summary of socio-economic vulnerabilities (global, unless otherwise stated) likely to exacerbate near-term global and regional impacts of climate change, global and regional (italics denote direct quotes from participating experts)

Table 2. Summary of socio-economic vulnerabilities (global, unless otherwise stated) likely to exacerbate near-term global and regional impacts of climate change, global and regional (italics denote direct quotes from participating experts)

Table 3. Crop sector adaptation themes and categories, synthesized from National Communications submitted by 21 African countries to the United Nations Framework Convention on Climate Change (UNFCCC)

Table 3. Crop sector adaptation themes and categories, synthesized from National Communications submitted by 21 African countries to the United Nations Framework Convention on Climate Change (UNFCCC)