WMO declares 2023 as the hottest year on record ahead of the Copenhagen Climate Ministerial

The World Meteorological Organization (WMO) released its “State of the Global Climate 2023” report on March 19, 2024, confirming 2023 as the warmest year on record. The report is published ahead of the Copenhagen Climate Ministerial on March 21 and 22, where climate leaders and ministers from around the world will gather to push for accelerated climate action.

The WMO report confirmed that 2023 was the warmest year on record, with the global average near-surface temperature at 1.45 °C / 2.61 °F (with a margin of uncertainty of ± 0.12 °C / 0.21 °F) above the pre-industrial baseline. This shattered the record of the previous warmest years, 2016 at 1.29 ± 0.12  °C (2.3 ± 0.2 °F) above the 1850 – 1900 average and 2020 at 1.27 ± 0.13  °C (2.28 ± 0.13 °F).

WMO’s value slightly differs from Berkley’s Global Temperature Report for 2023 released in January which estimated that the global annual average for 2023 was 1.54 ± 0.06 °C (2.77 ± 0.11 °F) above the average during the period 1850 to 1900, which is traditionally used a reference for the preindustrial period.

The long-term increase in global temperature was attributed to the increased concentrations of greenhouse gases in the atmosphere and the shift from La Niña to El Niño conditions in the middle of 2023 which contributed to the rapid rise in temperature from 2022 to 2023.

When looking at specific indicators from the reports, global average sea-surface temperatures (SSTs), for example, were at a record high from April onwards, with the records in July, August, and September broken by a particularly wide margin. Exceptional warmth was recorded in the eastern North Atlantic, the Gulf of Mexico and the Caribbean, the North Pacific and large areas of the Southern Ocean, with widespread marine heatwaves.

Antarctic sea-ice extent reached an absolute record low for the satellite era (since 1979) in February 2023 and remained at a record low for the time of year from June till early November. The annual maximum in September was 16.96 million km² (7.7 million miles²), roughly 1.5 million km² (579 150 miles²) below the 1991–2020 average and 1 million km² (386 100 miles²) below the previous record low maximum.

According to preliminary data, the global set of reference glaciers suffered the largest loss of ice on record (since 1950), driven by extreme melt in both western North America and Europe.

Extreme weather and climate events had major socio-economic impacts on all inhabited continents, including major floods, tropical cyclones, extreme heat and drought, and associated wildfires, WMO said.

Flooding linked to extreme rainfall from Mediterranean Cyclone Daniel (also known as Medicane Marquesa) affected Greece, Bulgaria, Türkiye, and Libya with a particularly heavy loss of life in Libya in September.

Tropical Cyclone “Freddy” in February and March was one of the world’s longest-lived tropical cyclones with major impacts on Madagascar, Mozambique and Malawi.

Tropical Cyclone “Mocha” in May, was one of the most intense cyclones ever observed in the Bay of Bengal and triggered 1.7 million displacements across the sub-region from Sri Lanka to Myanmar and through India and Bangladesh, and worsened acute food insecurity.

Hurricane “Otis” intensified to a maximum Category 5 system in a matter of hours – one of the most rapid intensification rates in the satellite era. It hit the Mexican coastal resort of Acapulco on October 24, causing economic losses estimated at around US$15 billion, and killing at least 47 people.

Some of the most significant heatwaves were in southern Europe and North Africa, especially in the second half of July. Temperatures in Italy reached 48.2 °C (118.8 °F), and record-high temperatures were reported in Tunis (Tunisia) 49 °C (20.2 °F), Agadir (Morocco) 50.4 °C (122.7 °F) and Algiers (Algeria) 49.2 °C (120.5 °F).

Canada’s 2023 wildfire season was the worst on record. The total area burned nationally for the year was 14.9 million ha (36.8 million acres), more than seven times the long-term average. The fires also led to severe smoke pollution, particularly in the heavily populated areas of eastern Canada and the northeastern United States. The deadliest single wildfire of the year was in Hawaii, with at least 100 deaths reported – the deadliest wildfire in the USA for more than 100 years – and estimated economic losses of US$5.6 billion.

The Greater Horn of Africa region, which had been experiencing long-term drought, suffered substantial flooding in 2023, particularly later in the year. The flooding displaced 1.8 million people across Ethiopia, Burundi, South Sudan, Tanzania, Uganda, Somalia, and Kenya in addition to the 3 million people displaced internally or across borders by the five consecutive seasons of drought in Ethiopia, Kenya, Djibouti, and Somalia.

Long-term drought persisted in north-western Africa and parts of the Iberian Peninsula, as well as parts of central and southwest Asia. It intensified in many parts of Central America and South America. In northern Argentina and Uruguay, rainfall from January to August was 20 to 50% below average, leading to crop losses and low water storage levels.

Weather and climate hazards also exacerbated challenges with food security, population displacements, and impacts on vulnerable populations. They continued to trigger new, prolonged, and secondary displacement and increased the vulnerability of many who were already uprooted by complex multi-causal situations of conflict and violence.

WMO’s report was published ahead of the Copenhagen Climate Ministerial on March 21 and 22, where climate leaders and ministers from around the world will gather for the first time since COP28 in Dubai to push for accelerated climate action. Enhancing countries’ Nationally Determined Contributions (NDCs) ahead of the February 2025 deadline will be high on the agenda, as will delivering an ambitious agreement on financing at COP29 to turn national plans into action. It also sets the scene for a new climate action campaign by the UN Development Programme and WMO to be launched on March 21.

According to the E3G think tank, the Copenhagen meeting is the beginning of the ‘Road to Belem.’ The term refers to the period leading up to COP30, which is scheduled to take place in Belem, Brazil in November 2025 when ‘governments will be judged on the delivery of a gamut of climate promises.’ This includes commitments to transition away from fossil fuels, address climate, health and biodiversity, and strengthen action on adaptation and loss and damage.

References:

¹ Climate change indicators reached record levels in 2023: WMO – WMO – March 19, 2024

Featured image credit: WMO (stillshot)