GlobalTemperature

Data Sources

GlobalTemperature integrates 12 datasets from authoritative scientific sources. All data is publicly available and regularly updated.

Temperature Baseline

All temperature anomalies in this domain are expressed relative to the 1850-1900 pre-industrial baseline, as recommended by IPCC AR6. The raw NASA GISTEMP data uses a 1951-1980 baseline, which we convert using an offset of +0.10°C.

Source Details

NASA GISTEMP v4

The Goddard Institute for Space Studies Surface Temperature Analysis (GISTEMP) combines land-surface air temperatures from NOAA GHCN with sea surface temperatures from ERSST. It is one of three primary global temperature records (alongside NOAA GlobalTemp and HadCRUT).

• URL: data.giss.nasa.gov/gistemp
• Update frequency: Monthly
• Uncertainty: ~0.05°C for recent decades

NOAA Mauna Loa CO2

The longest continuous record of atmospheric CO2, started by Charles David Keeling in 1958. Known as the "Keeling Curve," it shows both the seasonal cycle and long-term trend of CO2.

• URL: gml.noaa.gov/ccgg/trends
• Update frequency: Monthly
• Pre-industrial reference: 280 ppm (from ice cores)

NOAA Global Monitoring Laboratory - Methane

Global average methane (CH4) concentration from a network of measurement stations. Methane is the second most important greenhouse gas, with a warming potential ~80x CO2 over 20 years.

• URL: gml.noaa.gov/ccgg/trends_ch4
• Pre-industrial reference: ~722 ppb
• Current level: ~1920 ppb (+166% above pre-industrial)

NSIDC Sea Ice Index

Arctic sea ice extent from passive microwave satellite sensors. September extent (annual minimum) has declined by approximately 13% per decade since 1979.

• URL: nsidc.org/data/seaice_index
• Satellite era: 1979-present
• Key metric: September minimum extent

NOAA NCEI Ocean Heat Content

Ocean heat content from in-situ measurements (ships, buoys, Argo floats). The ocean has absorbed over 90% of the excess heat from global warming.

• URL: ncei.noaa.gov/access/global-ocean-heat-content
• Depths: 0-700m (1955-) and 0-2000m (2005-)
• Units: 10²² Joules anomaly

NOAA Laboratory for Satellite Altimetry - Sea Level

Global mean sea level from satellite radar altimeters (TOPEX/Poseidon, Jason series). Current rate of rise is approximately 3.4 mm/year.

• URL: star.nesdis.noaa.gov/socd/lsa/SeaLevelRise
• Satellite era: 1992-present
• Reference: 1993 baseline

Our World in Data / Global Carbon Project

CO2 emissions by country from fossil fuels and cement production. Data compiled by the Global Carbon Project and curated by Our World in Data.

• URL: github.com/owid/co2-data
• Coverage: 200+ countries, 1750-present
• Units: Million tonnes CO2/year

Domain Variations

GlobalTemperature provides 93 tools across 8 variations, each with a specific focus: