The NASA website is a great place to find authoritative data on many aspects of climate change including changing levels of greenhouse gases.
For example, NASA has just published data showing the latest measurements of carbon dioxide in the atmosphere. The graph below shows measurements taken at the Mauna Loa Observatory, Hawaii. On 16 January 2019 carbon dioxide was present at 410.48 ppm, a continuing further increase on earlier levels.
Measurements of carbon dioxide levels over the last 400,000 years have been determined by the technology of ice core analysis – graph below. The ice cores include small bubbles of air that contain samples of the atmosphere at the time.The great increase in current levels of carbon dioxide compared to earlier peaks is evident in the graph.
NASA carries out two major studies that look specifically at carbon dioxide:
Atmospheric Infrared Sounder (AIRS)
This instrument was launched in 2002 as part of NASA’s Earth Observing System of satellites. Along with two other NASA projects – Advanced Microwave Sounding Unit (AMSU) and the Humidity Sounder for Brazil (HSB), AIRS looks at the entire atmospheric column from the surface to the top of the atmosphere.
Measurements are taken of:
- surface emissivity and temperature
- atmospheric temperature and humidity
- cloud amount and height
- spectral outgoing infrared radiation
Orbiting Carbon Observatory-2 (OCO-2)
This project measures atmospheric carbon dioxide with a high degree of precision, resolution and coverage over the seasonal cycle. The instrument contains three high-resolution gating spectrometers that measure the near-infrared absorption of sunlight by carbon dioxide and molecular oxygen.
The full data from both projects can be seed on the carbon dioxide satellite data section of the NASA site.