Warming world: Surface measurements

  • Image: NASA

  • Image: CambridgeBayWeather

  • Image: CambridgeBayWeather

  • Image: Argo program/ www.argo.ucsd.edu

  • Image: Argo program / www.argo.ucsd.edu

  • Image: NASA

  • Image: NASA Goddard Space Flight Center

    Scientists record surface temperature at thousands of locations worldwide. Weather stations on land measure air temperature, using thermometers sheltered by Stevenson screens. Ocean temperature is measured by ships and Argo floats. Both air and sea surface temperature measurements show a long-term warming trend since 1900.