An existential threat – Part 3

Climate change impacts on human health and wellbeing.

Human health and wellbeing

Impacts of climate change cause widespread harm to human health, with children often suffering the most. Food shortages, polluted air, contaminated or scarce supplies of water, an expanding area of vectors causing infectious diseases, and more intensely allergenic plants are among the harmful impacts. More extreme weather events cause physical and psychological harm. World health experts have concluded with ‘‘very high confidence’’ that climate change already contributes to the global burden of disease and premature death.

IPCC projects the following trends, if global warming continues to increase, where only trends assigned very high confidence or high confidence are included: (i) increased malnutrition and consequent disorders, including those related to child growth and development, (ii) increased death, disease and injuries from heat waves, floods, storms, fires and droughts, (iii) increased cardio-respiratory morbidity and mortality associated with ground-level ozone. While IPCC also projects fewer deaths from cold, this positive effect is far outweighed by the negative ones.

Growing awareness of the consequences of human-caused climate change triggers anxiety and feelings of helplessness. Children, already susceptible to age-related insecurities, face additional destabilizing insecurities from questions about how they will cope with future climate change. Exposure to media ensures that children cannot escape hearing that their future and that of other species is at stake, and that the window of opportunity to avoid dramatic climate impacts is closing. The psychological health of our children is a priority, but denial of the truth exposes our children to even greater risk.

Hansen et al., 2013, Assessing ‘‘Dangerous Climate Change’’: Required Reduction of Carbon Emissions to Protect Young People, Future Generations and Nature, p. 6.1

In 2013 and 2014, the World Bank Group published a series of reports detailing how climate change impacts will be felt disproportionately in developing countries around the equatorial regions.2

2013 report –

With a focus on Sub-Saharan Africa, South East Asia and South Asia, the report examines in greater detail the likely impacts for affected populations of present day, 2°C and 4°C warming on critical areas like agricultural production, water resources, coastal ecosystems and cities.

The result is a dramatic picture of a world of climate and weather extremes causing devastation and human suffering. In many cases, multiple threats of increasing extreme heat waves, sea-level rise, more severe storms, droughts and floods will have severe negative implications for the poorest and most vulnerable.

In Sub-Saharan Africa, significant crop yield reductions with 2°C warming are expected to have strong repercussions on food security, while rising temperatures could cause major loss of savanna grasslands threatening pastoral livelihoods. In South Asia, projected changes to the monsoon system and rising peak temperatures put water and food resources at severe risk. Energy security is threatened, too. While, across South East Asia, rural livelihoods are faced with mounting pressures as sea-level rises, tropical cyclones increase in intensity and important marine ecosystem services are lost as warming approaches 4°C.

Across all regions, the likely movement of impacted communities into urban areas could lead to ever higher numbers of people in informal settlements being exposed to heat waves, flooding, and diseases.

World Bank. 2013. Turn Down the Heat: Climate Extremes, Regional Impacts, and the Case for Resilience.3

2014 report –

For this report, the third in the Turn Down the Heat series, we turned again to the scientists at the Potsdam Institute for Climate Impact Research and Climate Analytics. We asked them to look at the likely impacts of present day (0.8°C), 2°C and 4°C warming on agricultural production, water resources, cities and ecosystems across Latin America and the Caribbean, Middle East and North Africa, and parts of Europe and Central Asia.

Their findings are alarming.

In Latin America and the Caribbean, heat extremes and changing precipitation patterns will have adverse effects on agricultural productivity, hydrological regimes and biodiversity. In Brazil, at 2°C warming, crop yields could decrease by up to 70 percent for soybean and up to 50 percent for wheat. Ocean acidification, sea level rise, tropical cyclones and temperature changes will negatively impact coastal livelihoods, tourism, health and food and water security, particularly in the Caribbean. Melting glaciers would be a hazard for Andean cities.

In the Middle East and North Africa, a large increase in heat-waves combined with warmer average temperatures will put intense pressure on already scarce water resources with major consequences for regional food security. Crop yields could decrease by up to 30 percent at 1.5–2°C and by almost 60 percent at 3–4°C. At the same time, migration and climate-related pressure on resources might increase the risk of conflict.

In the Western Balkans and Central Asia, reduced water availability in some places becomes a threat as temperatures rise toward 4°C. Melting glaciers in Central Asia and shifts in the timing of water flows will lead to less water resources in summer months and high risks of torrential floods. In the Balkans, a higher risk of drought results in potential declines for crop yields, urban health, and energy generation. In Macedonia, yield losses are projected of up to 50 percent for maize, wheat, vegetables and grapes at 2°C warming. In northern Russia, forest dieback and thawing of permafrost threaten to amplify global warming as stored carbon and methane are released into the atmosphere, giving rise to a self-amplifying feedback loop.

World Bank. 2014. Turn Down the Heat: Confronting the New Climate Normal.4

The World Bank report ‘Groundswell’ states:5

Under all three scenarios in this report, there is an upward trend of internal climate migration in Sub-Saharan Africa, South Asia, and Latin America by 2050. In the worst-case or “pessimistic” scenario, the number of internal climate migrants could reach more than 143 million (around 86 million in Sub-Saharan Africa, 40 million in South Asia, and 17 million in Latin America) by 2050. The poorest people and the poorest countries are the hardest hit.

Across all scenarios, climate change is a growing driver of internal migration. Climate change impacts (crop failure, water stress, sea level rise) increase the probability of migration under distress, creating growing challenges for human development and planning. Vulnerable people have the fewest opportunities to adapt locally or to move away from risk and, when moving, often do so as a last resort. Others, even more vulnerable, will be unable to move, trapped in increasingly unviable areas.

Internal climate migration will intensify over the next several decades and could accelerate after 2050 under the pessimistic scenario due to stronger climate impacts combined with steep population growth in many regions.

World Bank Group, 2018, Groundswell – Preparing for internal climate migration.5
World Bank Group, 2018, – Preparing for internal climate migration.5
  1. Hansen J, Kharecha P, Sato M, Masson-Delmotte V, Ackerman F, et al. (2013) Assessing ‘‘Dangerous Climate Change’’: Required Reduction of Carbon Emissions to Protect Young People, Future Generations and Nature. PLoS ONE 8(12): e81648. doi:10.1371/journal.pone.0081648,
  3. World Bank. 2013. Turn Down the Heat: Climate Extremes, Regional Impacts, and the Case for Resilience. A report for the World Bank by the Potsdam Institute for Climate Impact Research and Climate Analytics. Washington, DC:World Bank. License: Creative Commons Attribution—NonCommercial–NoDerivatives3.0 Unported license (CC BY-NC-ND 3.0),[]
  4. World Bank. 2014. Turn Down the Heat: Confronting the New Climate Normal. Washington, DC: World Bank. License: Creative Commons Attribution—NonCommercial—NoDerivatives 3.0 IGO (CC BY-NC-ND 3.0 IGO),[]