Changes in atmospheric composition affect air quality, weather, climate, and critical constituents such as ozone and aerosols. Atmospheric composition is central to Earth system dynamics, since the atmosphere integrates surface emissions globally on time scales from weeks to years and involves several environmental issues. NASA’s research for furthering the understanding of atmospheric composition seeks to provide an improved prognostic capability for such issues. These issues include the recovery of stratospheric ozone and its effects on surface ultraviolet radiation, the evolution of greenhouse gases and their effects on climate, and the evolution of aerosols, clouds and tropospheric ozone and their effects on climate and air quality.
NASA works to provide monitoring and evaluation tools to assess the effects of climate change on ozone recovery and future atmospheric composition, improved climate forecasts based on the understanding of the forcings of global environmental change, and air quality forecasts that take into account the relationship between regional air quality and global climate change. Achievements in these areas via advances in observations, data assimilation, and modeling enable improved predictive capabilities for describing how future changes in atmospheric composition affect ozone, climate, and air quality. Drawing on global observations from space, augmented by suborbital and ground-based measurements, NASA is well positioned to address these issues.
Atmospheric Composition addresses the following questions:
- How is atmospheric composition changing?
- What trends in atmospheric composition and solar radiation influence global climate?
- How does atmospheric composition respond to and affect global environmental change?
- What are the effects of global atmospheric composition and climate changes on regional air quality?
- How will future changes in atmospheric composition affect ozone, climate, and global air quality?
The Upper Atmosphere Research Program (UARP) concentrates on observations to study processes that control ozone concentrations in the upper troposphere and stratosphere, and therefore surface ultraviolet radiation. The program funds numerous laboratory studies, ground-based network observations, and field campaigns that contribute to quantifying scientific understanding of ozone changes. These activities complement the observations from and data analysis using the NASA Aura EOS satellite as well as other satellites that observe the upper troposphere and stratosphere. Typical laboratory studies include kinetics studies of key reactions that either directly or indirectly destroy and create ozone or the precursors to ozone destroying compounds, as well as spectroscopic studies required to accurately monitor the key atmospheric constituents. Typical field studies include airborne in situ and remote sensing instrumentation for focused aircraft field campaigns, high altitude balloon remote sensing and in situ observations, and long term ground-based in situ and remote sensing programs (such as AGAGE and NDACC). The WMO/UNEP quadrennial assessments on ozone depletion, as mandated by the Montreal Protocol, rely heavily on many of these observations.
The Tropospheric Chemistry Program (TCP) seeks to improve measurement-based understanding of global tropospheric ozone and aerosol, including their precursors and transformation processes in the atmosphere. Ozone and aerosol are fundamental to both air quality and climate. The program emphasizes suborbital and ground-based measurements acquired during focused field deployments. Along with the other Atmospheric Composition programs, TCP also sponsors interpretation of these comprehensive but infrequent measurements to improve the continuous monitoring of ozone and aerosols from space and the improvement of prognostic models. TCP also supports limited laboratory studies that are directly relevant to improved understanding of tropospheric chemistry. Additional information regarding airborne campaigns that TCP has supported is available at http://www-air.larc.nasa.gov/missions.htm.
The Radiation Sciences Program (RSP) strives to develop a quantitative and predictive understanding of how aerosols, clouds, and radiatively active gases scatter and absorb radiation in the Earth’s atmosphere, especially as it relates to climate variability and change. The program supports studies to improve the theoretical understanding of radiative transfer as well as field measurements of aerosol and cloud particle concentration, composition, microphysics, and optical properties. These measurements include both airborne and surface-based remote and in situ measurements. The program also supports the analysis of satellite remote sensing and field data as well as the development of process models, which contribute to an Earth system modeling capability.
The Atmospheric Composition Modeling and Analysis Program (ACMAP) supports studies of air quality and oxidation efficiency in the troposphere, how pollution-sourced aerosols affect cloud properties, stratospheric chemistry and ozone depletion, and interactions between atmospheric chemistry and the climate. Studies of long-term trends in atmospheric composition are also of interest, particularly if a governing process can be identified. The program is particularly interested in studies that integrate observations from multiple instruments with models to address attribution and predictions. Use of satellite and suborbital data sets and ground-based measurements are encouraged for modeling constraints and verification where applicable.
Associated Earth Science Division Missions, Instruments, and Data Sets
Several current and planned missions are directly relevant to the Atmospheric Composition focus area. Currently operating satellite missions include Aqua, Aura, CALIPSO, CloudSat, Suomi NPP, Terra, and TRMM. Current Earth Venture suborbital investigations include ATTREX, CARVE, and DISCOVER-AQ. Satellite missions in development or planning include OCO-2, SAGE-III ISS, PACE, ACE, ASCENDS, and GEO-CAPE.
Relevant Earth Science Division Programs
Topics relevant to Atmospheric Composition are also found in the following program elements:
- Carbon Cycle Science
- Aura Science Team
- Orbiting Carbon Observatory-2 Science Team
- CloudSat/CALIPSO Science Team
- Rapid Response and Novel Research in Earth Science
- PACE Science Team
- Airborne Instrument Technology Transition
- Terra and Aqua Science Team
- Earth Science U.S. Participating Investigator
- Interdisciplinary Research in Earth Science
- NASA Data for Operation and Assessment
- New Investigator Program
- Health and Air Quality Applications
- Making Earth System data records for Use in Research Environments (MEaSUREs)
Hal Maring: Radiation Sciences Program
Ken Jucks: Upper Atmosphere Research Program
Richard Eckman: Atmospheric Composition Modeling and Analysis
Alex Pszenny: Tropospheric Composition Program