Global warming is visible across several independent measurements. NASA, the World Meteorological Organization (WMO), NOAA, and the U.S. Environmental Protection Agency (EPA) report record or near-record heat, rising greenhouse-gas concentrations, increasing ocean heat, widespread glacier loss, and continuing sea-level rise. The figures below specify the measurement period, baseline, geography, and source for each statistic.
Contents
- Temperature records
- Atmospheric greenhouse gases
- Ocean heat
- Sea ice and glaciers
- Sea-level rise
- What the records show together
Temperature records
2024 was Earth’s warmest year since modern record-keeping began in 1880, according to NASA’s 2024 warmest-year release. NASA measured global temperatures at 2.30°F (1.28°C) above its 1951–1980 baseline. Using a different reference period, NASA estimated that 2024 was about 2.65°F (1.47°C) warmer than the 1850–1900 pre-industrial average.
The warmth was not confined to one month. NASA reported 15 consecutive monthly temperature records from June 2023 through August 2024. It also reported that the past 10 consecutive years were the warmest 10 years in the record. NASA’s global temperature explainer adds a longer-term comparison: each of the last four decades was warmer than every decade before it back to 1850.
WMO’s State of the Global Climate 2024 assessed 2024 global mean near-surface temperature at 1.55°C ± 0.13°C above the 1850–1900 average. WMO judged 2024 likely to have been the first calendar year more than 1.5°C above that pre-industrial reference. WMO also identified 2024 as the warmest year in its 175-year observational record. For comparison, WMO placed 2023 at 1.45°C ± 0.12°C above the same average, and said 2015–2024 were individually the 10 warmest years on record.
Different agencies use different datasets, baselines, and analysis methods, so their values are not identical. NOAA’s Assessing the Global Climate in 2024 report measured the 2024 global surface temperature at 2.32°F (1.29°C) above the 20th-century average and ranked it highest in NOAA’s 1850–2024 record. NOAA said 2024 exceeded 2023 by 0.18°F (0.10°C), and was 2.63°F (1.46°C) above the 1850–1900 pre-industrial average.
| Measure | Reported 2024 result | Reference or record |
|---|---|---|
| NASA global temperature | 2.30°F (1.28°C) above baseline | 1951–1980 average |
| WMO near-surface temperature | 1.55°C ± 0.13°C above average | 1850–1900 average |
| NOAA global surface temperature | 2.32°F (1.29°C) above average | 20th-century average |
| NOAA pre-industrial comparison | 2.63°F (1.46°C) above average | 1850–1900 average |
NOAA also reported that all 10 warmest years since 1850 occurred during the decade ending in 2024. These rankings describe global averages; they do not mean every location experienced the same temperature in every month.
Atmospheric greenhouse gases
WMO’s State of the Global Climate 2024 reported that atmospheric carbon dioxide reached 420.0 ± 0.1 parts per million (ppm) in 2023. WMO expressed that concentration as 151% of the pre-industrial level. Atmospheric methane reached 1,934 ± 2 parts per billion (ppb) in 2023, or 265% of its pre-industrial concentration. Nitrous oxide reached 336.9 ± 0.1 ppb, or 125% of its pre-industrial concentration.
These are global atmospheric concentrations measured for 2023, not forecasts. The percentage comparisons use the pre-industrial reference described by WMO, while the concentration units describe the amount of each gas in the atmosphere.
NOAA’s BAMS State of the Climate 2024 report gave a later annual CO2 measure: globally averaged CO2 reached 422.8 ± 0.1 ppm in 2024. NOAA said this represented a 52% increase from the pre-industrial level of about 278 ppm. NOAA also reported that global mean CO2 growth rose from 0.6 ± 0.1 ppm per year in the early 1960s to an average of 2.4 ppm per year during 2011–2020.
The increase from 2023 to 2024 was 3.4 ppm, according to NOAA. NOAA said this matched 2015/16 as the highest annual increase in its record since the 1960s. The WMO and NOAA values refer to different measurement years and reporting series, so they should be read as separate source results rather than combined into one calculation.
Ocean heat
The ocean stores heat across a vast area and depth, making ocean heat content an important global warming indicator. WMO’s ocean heat content indicator reported that global ocean heat content reached its highest level in the 65-year observational record in 2024. The 2024 value exceeded the previous record, set in 2023, by 16 ± 8 zettajoules (ZJ).
The rate of ocean warming has also changed across the available periods. WMO estimated the 2005–2024 rate at 11.2–12.1 ZJ per year, equivalent to 0.99–1.07 watts per square metre (W/m²). For 1960–2005, the reported rate was 3.1–3.9 ZJ per year, or 0.27–0.34 W/m². Averaged across 1971–2024, global ocean heat content increased at 0.6 ± 0.1 W/m², equivalent to 6.8 ZJ per year.
NOAA’s Assessing the Global Climate in 2024 also reported record-high upper-ocean heat content. NOAA’s BAMS State of the Climate 2024 report found that mean annual global sea-surface temperature was record high and exceeded the 2023 record by 0.11°F (0.06°C). Sea-surface temperature is a surface measurement; ocean heat content includes heat stored in the ocean and is therefore a different indicator.
Sea ice and glaciers
NOAA reported that Arctic sea-ice extent averaged 4.03 million square miles in 2024, ranking seventh lowest on record. Antarctic sea-ice extent averaged 4.00 million square miles and ranked second lowest on record. These are annual average extents for the two polar regions, not measurements of ice thickness or total ice volume.
The same NOAA 2024 climate assessment counted 85 named tropical storms globally and 18 named tropical storms in the North Atlantic during 2024. Storm counts are presented here as observations for that year; they do not establish that every individual storm was caused by global warming.
Glaciers showed a broad loss signal. NOAA’s BAMS State of the Climate 2024 report said all 58 global reference glaciers lost mass in 2024. It identified 2024 as the year with the greatest average glacier ice loss in the 55-year record. NOAA also said 2024 was the second consecutive year in which all 58 reference glaciers lost mass.
Together, the glacier and sea-ice statistics describe different cryosphere measurements. Glacier mass tracks the gain or loss of ice in selected reference glaciers, while sea-ice extent measures the area covered by floating ice at the poles. Their units, locations, and record comparisons should not be treated as interchangeable.
Sea-level rise
NOAA’s A Look at 2024 report said global mean sea level set a new record for the 13th consecutive year. In 2024, global mean sea level was 105.8 millimetres above the 1993 satellite-altimetry baseline. It was 4.6 ± 1.4 mm higher than in 2023.
NOAA reported an average annual sea-level rise of 3.8 ± 0.4 mm per year since 1993. The baseline is important: the 105.8 mm figure is a height difference relative to the 1993 satellite-altimetry reference, while the annual figure is a rate averaged across the period beginning in 1993.
EPA’s Climate Change Indicators: Sea Level gives the same broad satellite-era trend in inches. EPA reported that global average sea level rose at 0.12 inches per year since 1993, about twice the 0.06-inch-per-year trend for 1880–2013. The two periods are not identical, and the EPA figures should remain associated with their stated time spans.
What the records show together
The measurements cover different parts of the climate system and different time windows. Temperature records show the recent global surface state; atmospheric concentrations show greenhouse gases in the air; ocean heat records track stored energy; ice measurements describe polar and glacier changes; and sea-level records capture a global consequence of warming oceans and melting land ice.
Several records are explicitly annual observations for 2024, including the warmest global temperatures reported by NASA, WMO, and NOAA, record ocean heat, record sea-surface temperature, widespread reference-glacier mass loss, and a record global mean sea level. Other measurements refer to 2023, such as WMO’s greenhouse-gas concentrations, or to multi-decade averages, such as WMO’s ocean-warming rates and NOAA’s sea-level trend.
The most useful comparison is therefore temporal and geographic: 2024 describes a record-hot year globally; 2015–2024 describes a decade of individually record-warm years in WMO’s assessment; 2005–2024 describes a faster ocean-warming period than 1960–2005 in WMO’s indicator; and 1993 onward defines NOAA’s satellite-altimetry sea-level baseline and trend. Keeping those scopes visible prevents a single number from being mistaken for a universal measurement of every part of the climate system.