Glacier in Iceland
Copyright© UN Photo/Eskinder Debebe
Background The impacts of climate change
Heat waves, floods, wildfires
The frequency and severity of extreme weather events, including cold spells and heat waves, droughts, hurricanes, floods and wildfires, are already increasing due to climate change. Between 1970 and 2019, more than two million people died as a result of weather- and climate-related disasters; over 80 per cent of these deaths occurred in developing countries. The number of weather-related disasters has increased fivefold over the past 50 years.
In addition, global warming is causing gradual environmental changes: melting glaciers, rising sea levels, ocean acidification, higher soil salinity, lower groundwater levels, desertification and loss of biodiversity. These changes threaten communities’ vital resources and livelihoods worldwide and could make entire habitats uninhabitable.
Development progress at risk
Climate change particularly affects the developing countries. This is due partly to their geographic location and their vulnerable infrastructure, but also to their limited capacities to take preparedness measures, protect their citizens and adapt to changing conditions.
Climate change thus threatens to cancel out previous development successes and create new hardships. The impacts are felt most severely by vulnerable groups:
- Rising temperatures, lack of rainfall and extreme weather events cause crop losses. Without adaptation measures, global agricultural yields could decline by 5 to 30 per cent by 2050.
- With global warming of 2 degrees Celsius, climate change is likely to put 40 per cent more people at risk of absolute water scarcity. Melting glaciers are already having a – sometimes catastrophic – impact on water supplies to communities in Asia and Latin America.
- Rising sea levels threaten communities in coastal regions throughout the world. Small island states such as Vanuatu, Kiribati and the Marshall Islands are especially at risk. Coastal megacities, including Bangkok, Manila, New York, Shanghai, Tokyo and Jakarta, have been identified as “vulnerability hotspots”.
- More frequent storms and floods destroy key infrastructure such as roads and health and education facilities. The direct economic losses caused by disasters over the last 20 years are valued at almost 3 trillion US dollars, almost double the figure for the previous two decades.
- Extreme heat, food and water shortages but also the spread of pathogens increase disease and mortality rates.
- Climate change could amplify existing conflict risks, such as competition over resources like land and water.
More poverty, more migration, more hunger
According to estimates from the World Bank, global warming could push up to 132 million more people into extreme poverty by 2030 unless there is urgent and comprehensive investment in climate change mitigation and adaptation measures. More than 200 million people could be forced to leave their homes by 2050. Within 50 years, 3.5 billion people could be affected by extreme heat. More than 800 million of the world’s people are already hungry; climate change could exacerbate the hunger crisis.
The poorest countries in particular lack the financial, institutional and technological resources that would enable them to mount a climate policy response. As the main contributors to climate change, the developed countries have a responsibility to lead by example and to do more to promote climate justice. They have pledged to support the developing countries’ efforts to make their economies climate-neutral and adapt to the unavoidable impacts of global warming.
As at: 13/10/2022