In 2023, the impacts of climate change have been dramatic worldwide. This year, the Earth experienced the hottest three-month period on record, with unprecedented surface temperatures and extreme weather events. Heatwaves, wildfires, floods, and hurricanes have raged across the globe, destroying lives and livelihoods.
Accelerating and unprecedented climate impacts are confirmed by OECD data. Systematic data on the evolution of climate-related hazards from countries covered under the International Programme for Action on Climate (IPAC), considering both OECD and OECD partner countries (including accession countries), confirm that climate impacts are accelerating and becoming even more extreme, exposing a greater share of the world’s population and land surface area. The 2023 climate-related extreme events are consistent with long-term trends.
The population exposed to extreme temperatures is growing rapidly. An estimated 11.3% more people are exposed to days with maximum temperatures exceeding 35°C in OECD and OECD partner countries in the period 2018-22 compared to the reference period 1981-2010, reaching over half a billion people. As a result, in 2022, over 45% of the population in OECD and OECD partner countries experienced at least two weeks of extreme temperatures. Temperatures recorded this year attest to the continuation of this trend, which not only has direct impacts but can also intensify hazards such as hurricanes, heatwaves, droughts, and extreme rainfall, affecting vulnerable populations, ecosystems, and economic infrastructure.
Population exposure to tropical nights (above 20°C at night) is increasing. Twenty countries — out of 51 OECD and partner countries — experienced a 10% increase in the population exposed to tropical nights over the period 2018-22 compared to 1981-2010. Korea (28%), Italy (18%) and Greece (16%) had the highest increase in population exposed to more than eight weeks of tropical nights.
Agricultural droughts in OECD and partner countries are intensifying. Countries such as Argentina, Brazil and Romania have experienced an average fall in soil moisture of more than 6% in the last four decades (period comparison average 2018-2022 compared to 1981-2010). These drought conditions can be even more acute at the sub-national level and during specific seasons, generating additional social and economic impacts.
Wildfires have been raging at unprecedented scales with a record-breaking land area burnt this year. An increasing area of forest land is exposed to wildfires across the OECD and partner countries. Between 2000-2003 and 2019-2022, the percentage of forest exposed to wildfires increased from 15% to 18%.
Increasing mean temperatures alter rainfall patterns affecting agricultural production and increasing vulnerability. Six out of the ten countries across OECD and OECD partners whose cropland area is the most exposed to extreme precipitation events are also highly dependent on agriculture as a share of GDP. For example, the countries with the highest share of cropland are exposed to extreme precipitation events between 2018 and 2022 included Indonesia (31.6%), Colombia (13.2%), Costa Rica (9.8%), Peru (8%) and Brazil (3.3%). This illustrates how climate change also threatens national and global food security.
Many countries are exposed to river and coastal flooding. Flooding events in 2023 were devastating and are likely to continue. Over 18% of the population of OECD and partner countries are exposed to the risk of river flooding. For some countries this can be as high as 40%. Similarly, over 2.6% of the population in OECD and partner countries are exposed to the risk of coastal flooding.