Many of the TROPESS-MUSES data products are focused on air pollution. Routine standard products from TROPESS-MUSES include vertically-resolved profiles for ozone (O3), carbon monoxide (CO), water vapor (H2O), deuterated water vapor (HDO) and methane (CH4). Ozone (O3) profiles, atmospheric temperature, concentrations of water vapor (H2O) and deuterated water vapor (HDO), carbon monoxide (CO) and methane (CH4). TROPESS-MUSES data products also include specially processed products, including ammonia (NH3), methanol (CH3OH), formic acid (HCOOH), carbonyl sulfide (OCS), and Peroxyacetyl nitrate (PAN). The TROPESS data products will provide continuity of tropospheric composition measurements and data for NASA for the following species:

TROPESS Trace Gas Species and their Importance in the Atmosphere
Chemical Formula
Long Name
Brief description of importance in the atmosphere
COCOCarbon monoxideCO is one of the six major air pollutants regulated in the United States and in many other nations around the world. When carbon-based fuels, such as coal, wood, and oil, burn incompletely or inefficiently, they produce carbon monoxide. CO is spread by winds and circulation patterns throughout the lower atmosphere (troposphere). Although CO itself is not an important greenhouse gas, it indirectly influences the abundance and lifetime of tropospheric ozone (O3) and methane (CH4), and thus indirectly impacts Earth’s chemistry and climate. 1
CH4CH4MethaneCH4 is the world’s second largest contributor to greenhouse warming and is emitted from fossil fuel, agricultural, biomass burning and biofuels, and wetland sources.2
O3O3OzoneGround level ozone, a potent greenhouse gas and atmospheric pollutant, is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOCs), which are atmospheric pollutants emitted by cars, power plants, and industrial sources. Ozone is important for regulating levels of hydroxyl radical, an atmospheric oxidant that determines the lifetime of many gases. In high concentrations, surface ozone is also toxic to humans and plants.3
HDO_H2OHDODeuterium content of water vaporWater is made up of molecules comprising two atoms of hydrogen and one atom of oxygen (H2O). There are also several isotopes (chemically identical atoms with the same number of protons, but differing numbers of neutrons, and therefore mass) of both oxygen and hydrogen. Deuterium is one of the two stable isotopes of hydrogen:
  • 1H (with one proton and no neutrons, which is 99.985 percent of the hydrogen in water)
  • 2H (also known as deuterium (D), with one proton and one neutron).
The isotopic ratio of water vapor is sensitive to the evaporation and condensation history of water. As moist air travels poleward and cools, water molecules containing heavier isotopes will preferentially fall out in precipitation (rain). During evaporation, the opposite occurs – it takes more energy to evaporate the water molecules containing a heavy isotope from the surface of the ocean. Both processes, known as fractionation, are temperature dependent. In this way, scientists examine the isotopic ratio of atmospheric water vapor and compare the result with the isotopic ratio of an average ocean water standard known as SMOW (Standard Mean Ocean Water) to understand changes in Earth’s weather and climate patterns.4,5
NH3NH3AmmoniaAmmonia is involved in the formation of aerosol PM2.5 particles, which have adverse health effects, and impacts soil acidification, biodiversity, and the nitrogen cycle. Ammonia is produced from various sources, including agricultural emissions, however, there is widespread uncertainty in the magnitude and seasonality of ammonia emissions, which hinders the development of control measures.6
PANC2H3NO5Peroxyacetyl nitratePAN is a toxic chemical that is an important component of smog formation. PAN interacts with the various forms of reactive nitrogen. Reactive nitrogen is a term used for nitrogen compounds that support growth directly or indirectly, including all forms of nitrogen that are biologically, photochemically, and radiatively active, such as ammonia and nitrous oxide. Reactive nitrogen plays a major role in ozone production, and PAN facilitates its long-range transport. 7
CH3OHCH3OHMethanolMethanol (CH3OH) is one of the most abundant organic gases in the atmosphere (exceeded only by methane). It plays a key role in the oxidative capacity of the atmosphere. The primary sources of atmospheric methanol are the growth and decay of plants and biomass burning. As a biomass burning product, CH3OH, especially when used in conjunction with tracers measured by TROPESS-MUSES, can help determine the extent to which fire emissions affect the composition of the upper troposphere / lower stratosphere.8
HCOOHHCOOHFormic acidFormic acid is one of the most abundant acids in the atmosphere and has an important influence on precipitation chemistry and acidity. Formic acid accounts for airborne acidity and is a leading contributor to acid dry deposition.
TROPESS Atmospheric Variables and their Importance in the Atmosphere
MUSE product type
Long name
Brief description of importance in the atmosphere
O3_IRKsOzone Instantaneous Radiative KernelsThe ozone IRK provides unique information for questions of chemistry-climate coupling since this is a direct measure of the radiative role of ozone which explicitly accounts for more dominant radiative processes such as water vapor, temperature and clouds. These products can be compared to climate model predictions of the same quantities. They can also be used to estimate the radiative bias of the model due to their ozone bias.
T_surfSurface temperatureSurface Temperature is a scientific product retrieved over both land and ocean that is used in quality assessments of gas product retrievals. It is closely related to surface-leaving infrared radiance.
TATMAtmospheric temperatureAtmospheric Temperature is a scientific product jointly retrieved with chemical species. It is used in quality assessments of gas product retrievals, and in a supporting role of studies of ozone and its precursors.