Gases that trap heat in the atmosphere are called greenhouse gases (GHGs). Since the industrial revolution in the mid-1800s, human activities have increased the concentrations of GHGs in the atmosphere. Airborne, satellite, and ground-based instruments measure the composition of GHGs in the atmosphere, providing insight into how their composition is changing over time.
This Data Pathfinder is designed to help guide you through the process of selecting and using datasets applicable to monitoring greenhouse gases, with guidance on resolutions and direct links to the data sources. If you are new to remote sensing, the What is Remote Sensing? Backgrounder provides a good overview. In addition, NASA's Applied Remote Sensing Training Program (ARSET) provides numerous training modules, including Fundamentals of Remote Sensing.
If you have specific questions about how to use data, tools, or resources mentioned in this Data Pathfinder, please visit the Earthdata Forum. Here, you can interact with other data users and NASA subject matter experts on a variety of Earth science research and applications topics.
The datasets in this Data Pathfinder can be downloaded using Earthdata Search. Learn more about how to use Earthdata Search and other tools to visualize and explore data in the Tools for Data Access and Visualization section below.
An Overview of Greenhouse Gases
Life on Earth depends on energy from the Sun. About half the light energy reaching Earth's atmosphere passes through the air and clouds to the surface, where it is absorbed and radiated in the form of infrared heat. Nearly 90% of this heat is then absorbed by greenhouse gases and re-radiated, slowing heat loss to space. GHGs include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), chlorofluorocarbons (CFCs), ozone (O3), and water vapor (H2O).
Since the industrial revolution in the mid-1800s, human activities, such as the burning of fossil fuels and the clearing of land for agriculture, have increased the concentrations of GHGs in the atmosphere. The planet's average surface temperature has risen about 2.12° Fahrenheit (1.18° Celsius) since the late 19th century, and 10 of the warmest years on record have been observed since 2005. In its Sixth Assessment Report, the Intergovernmental Panel on Climate Change concluded that it is unequivocal that the increase of carbon dioxide, methane, and nitrous oxide in the atmosphere over the industrial era is the result of human activities and that human influence is the principal driver of many changes observed across the atmosphere, ocean, cryosphere and biosphere.
Remotely sensed GHG data are used in atmospheric models to estimate the sources and sinks of these gases. These data allow researchers to employ a top-down approach to emissions inventories, as opposed to a bottom-up approach that involves compiling an inventory of emissions from various sources. Satellite and aircraft-borne remote sensors can cover more area than in situ sensors and have the potential to shed light on sources and hotspots of GHG emissions, such as methane leaks or the effects of droughts and heatwaves, that may not be known from the bottom-up bookkeeping approach.