TES measures a number of greenhouse gases thought to influence the global warming of the lower atmosphere. Among the most important are the following:

H₂O

Water vapor is the most important greenhouse gas. Not only are its infrared absorption features widespread and strong, but it also displays a significant continuum absorption. Thus, while not one of the "gases of concern" in the sense of anthropogenic modification, the feedbacks engendered by the higher water content of a warmer atmosphere (and, potentially, greater cloud cover) are an important element of these studies. Furthermore, water vapor, through continua centered at 100 and 1600 cm^-1, is a crucial element in the radiative balance of the upper troposphere. TES routinely measures humidity (water vapor) profiles with a precision better than 10%.

Ozone

Ozone is an important contributor to Earth's radiative balance. It is both a major absorber of incoming UV in the stratosphere (leading to stratospheric heating) and a strong emitter in the thermal infrared. TES can contribute measurements of ozone in the lower atmosphere, but a significant fraction of the total column is above the region where TES performance becomes marginal (> 30 km). Thus, this part of the problem requires input from other instruments (e.g., MLS). Retrievals are good from the surface to the lower stratosphere.

CH₄

Monitoring of methane, which is a significant greenhouse gas, is a secondary goal for TES. Profile accuracies of better than 10% are feasible.

CO₂

TES uses carbon dioxide to determine temperature/pressure profiles. However, CO₂ is continuously monitored by in situ sensors to a precision well beyond that available from remote sensors.