Dr. Jennifer Wei of the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) recently attended the 8th International Workshop on Greenhouse Gas Measurements from Space, which took place June 18-20 in Pasadena, California. The workshop was jointly sponsored by the NASA Jet Propulsion Laboratory (JPL) and the California Institute of Technology (CalTech), and took place at Caltech’s Pasadena campus. The hosts of the meeting were the team assembled at JPL for the Orbiting Carbon Observatory-2 (OCO-2) mission.
At the workshop, Dr. Wei presented a poster entitled “Greenhouse Gas Data Sets and Associated Services at the NASA GES DISC”
. Her co-authors were Andrey Savtchenko, Bruce Vollmer, Thomas Hearty, and Arif Albayrak. The poster (in PDF) can be downloaded from this link
The meeting featured presentations of carbon dioxide (CO2
) data from scientists associated with several different instruments and missions. One of the notable missions represented was the Japanese Greenhouse gases Observing Satellite (GOSAT)
, illustrated in Figure 1. The workshop also featured discussions of measurements of other greenhouse gases, such as methane (CH4
) and nitrous oxide (N2
O). Greenhouse gas data are acquired by several instruments in orbit now, including the Atmospheric Infrared Sounder (AIRS)
on the Aqua satellite (Figure 2) and the Cross-track Infrared Sounder (CrIS)
on the recently launched NPOESS Preparatory Project Suomi mission. The development status of future satellite greenhouse gas monitoring missions were also presented to the attendees of the workshop, including the Orbiting Carbon Observatory-2 (OCO-2), CarbonSat, MicroCarb, GOSAT-II, and ASCENDS.
Figure 1. Diagram of GOSAT observational characteristics.
Figure 2. AIRS is an instrument on the Earth Observing System Aqua satellite.
The GES DISC provides carbon dioxide data from the Atmospheric CO2
Observations from Space (ACOS) Project (which uses GOSAT radiances), and the AIRS instrument on NASA’s Aqua satellite. These data sets can be accessed via the GES DISC Mirador site (http://mirador.gsfc.nasa.gov/
) and downloaded from the GES DISC archive utilizing FTP or OpenDAP.
Different satellite instruments use different technologies and data retrieval algorithms, and therefore each instrument may provide slightly different results. The example shown in Figure 3 displays the average of Northern Hemispheric CO2 concentration (2003-2012) observed from the AIRS mid-tropospheric CO2 (version 5; see the corresponding averaging kernel function as the red curve in Figure 4) and from ACOS total column CO2 (v.2.9, see the corresponding averaging kernel function as the blue curve in Figure 4).
Figure 3. Time-series of Northern Hemispheric CO2 data from AIRS and ACOS for the period 2003-2012 (ACOS data commence in 2009). The black curve is AIRS mid-tropospheric CO2, and the yellow curve is ACOS total column CO2. Click on the image to view a much larger full size version.
Figure 4. Averaging kernel functions for AIRS and ACOS. These curves show an approximation of how greenhouse gas concentrations at different atmospheric altitudes contribute to the data acquired by the instrument.
The planned OCO-2 mission will provide such data at increased spatial and temporal resolution. Data from OCO-2 will be archived and distributed by the GES DISC.
Article by Jennifer Wei; additional editing by Andrey Savtchenko, Bruce Vollmer, and Bill Teng. Editing and Web publishing by James Acker.
GOSAT is a mission of the Japan Aerospace Exploration Agency (JAXA). ACOS is a NASA project operating from the NASA Jet Propulsion Laboratory (JPL).
The GES DISC is a NASA earth science data center, part of the NASA Earth Science Data and Information System (ESDIS) Project.
Questions and comments? Email the NASA GES DISC Help Desk: firstname.lastname@example.org