WMO Report Highlights Record-breaking Climate Change Indicators in 2023

The World Meteorological Organization (WMO) released its State of the Global Climate 2023 report, revealing unprecedented levels of climate change indicators. These indicators underscore the urgent need for global action to mitigate the impacts of climate change.

Greenhouse Gas Levels

• Carbon dioxide, methane, and nitrous oxide concentrations reached record-high levels in 2023.
• Carbon dioxide levels measured at 417.9 ± 0.2 parts per million (ppm), methane at 1923 ± 2 parts per billion (ppb), and nitrous oxide at 335.8 ± 0.1 ppb.
• These levels exceed pre-industrial (1750) levels by 150%, 264%, and 124%, respectively.
• Methane and nitrous oxide witnessed notable increases, with methane recording the second-highest rate of increase on record.

Surface Temperatures

• The global average near-surface temperature in 2023 was 1.45 ± 0.12°C above the 1850-1900 average, making it the warmest year on record.
• This significant increase surpassed previous record holders, 2016 and 2020, by a considerable margin.
• The past nine years (2015-2023) ranked as the warmest on record.

Ocean Heat and Acidification

• Ocean heat content in 2023 reached unprecedented levels, with the highest amount of heat stored in the oceans.
• The rate of ocean warming accelerated in the past two decades, particularly from 2005-2023.
• Sea-level rise hit a record high since 1993, attributed to ocean warming and melting glaciers and ice sheets.
• Marine heatwaves occurred in most of the global ocean, with a notable increase in average daily coverage compared to previous years.

Antarctic Sea Ice and Glacier Retreat

• Arctic sea ice extent remained below normal, marking the fifth and sixth lowest extents in the satellite record for the annual maximum and minimum, respectively.
• Antarctic sea ice extent reached an all-time low for the satellite era in February.
• Global glaciers experienced a significant loss in mass balance, particularly in western North America and Europe, with Switzerland’s glaciers losing around 10% of their remaining volume in two years.

Ocean Acidification

• Ocean acidification continued to worsen, impacting biodiversity, habitats, and fisheries.
• The acidity in the open oceans reached its lowest levels in at least 26,000 years, posing severe threats to marine ecosystems.