The fact that 2023 was the hottest year on record that smashed the global temperature record has already been confirmed by the World Meteorological Organization (WMO).
Now, according to the State of Global Climate report, which reconfirms 2023 as the “hottest year on record by clear margin”, on an average day in the year nearly one third of the global ocean remained gripped by a marine heatwave, harming vital ecosystems and food systems.
“Towards the end of 2023, over 90 per cent of the ocean had experienced heatwave conditions at some point during the year. 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 according to preliminary data,” as per the latest WMO report released ahead of the World Meteorological Day on March 23.
Records were broken for ocean heat, sea level rise, the Antarctic sea ice loss and glacier retreat. The extreme weather undermined socio-economic development. However, the renewable energy transition provides hope, it said.
“Heatwaves, floods, droughts, wildfires and rapidly intensifying tropical cyclones caused misery and mayhem, upending every-day life for millions and inflicting many billions of dollars in economic losses,” according to the WMO State of the Global Climate 2023 report.
Alarming state of oceans, sea ice, glaciers
The unprecedented ocean warmth, glacier retreat and Antarctic sea ice loss is cause for particular concern, according to the WMO statement.
In 2023, global mean sea level reached a record high in the satellite record (since 1993), reflecting continued ocean warming (thermal expansion) as well as the melting of glaciers and ice sheets.
The rate of global mean sea level rise in the past 10 years (2014–2023) is more than twice the rate of sea level rise in the first decade of the satellite record (1993–2002).
Meanwhile, Antarctic sea-ice extent reached an absolute record low for the satellite era (since 1979) in February 2023 and remained at record low for the time of year from June till early November.
The annual maximum in September was 16.96 million km2, roughly 1.5 million km2 below the 1991–2020 average and 1 million km2 below the previous record low maximum, it said
Arctic sea-ice extent remained well below normal, with the annual maximum and minimum sea ice extent being the fifth and sixth lowest on record respectively.
“There are two principal ice sheets, the Greenland Ice Sheet and the Antarctic Ice Sheet. Combining the two ice sheets, the seven highest melt years on record are all since 2010, and average rates of mass loss increased from 105 Gigatonnes per year from 1992–1996 to 372 Gigatonnes per year from 2016–2020. This is equivalent to about 1 mm per year of global sea level rise attributed to the ice sheets in the latter period. Source: TNS