GHGs Trend Viewer
with GOSAT long-term target observations

GHG long-term trend viewer user guide -ACOS-

Last update: 2017/07/25

1. Introduction

The Greenhouse gases Observing SATellite "IBUKI" (GOSAT) is designed to measure the concentration of major greenhouse gases from space. GOSAT was launched successfully on January 23, 2009. GOSAT Project is a joint effort promoted by the Japan Aerospace Exploration Agency (JAXA), the National Institute for Environmental Studies (NIES) and the Ministry of the Environment (MOE).

NASA ACOS (Atmospheric CO2 Observations from Space) team analyzes GOSAT observational data and retrieves global distribution of carbon dioxide (CO2). ACOS Level-2 product that contains full physics retrievals of column-averaged dry air mole fractions of CO2 (XCO2) is now publicly available. We are also planning to add other Level 2 products. NIES V02.71 Level 2 product will be added after its validation is completed.

The GHG long term trend viewer presents quick view and pick up data set of the target observation sites, where users are interested. Most of the target observations requested by the RA researchers are not included in the list.

2. Data description

About data category

  • Airport (CONTRAIL)
    The CONTRAIL (Comprehensive Observation Network for TRace gases by AIrLiner) project is being jointly conducted by NIES (National Institute for Environmental Studies), the MRI (Meteorological Research Institute), JAL (Japan Airlines), JAMCO (JAMCO Corporation) and JAL-F (JAL Foundation). The CONTRAIL Database contains all the CO2 data measured by CME, as well as the information from the aircraft data system (aircraft position, temperature, wind direction and wind speed). These data have been used for GOSAT validation. GOSAT has targeted airports in serve.
  • Possible Emission Source
    Possible large emission source site
  • Megacity
    Highly populated cities urban area
  • Calibration
    Vicarious calibration site
  • TCCON (Total Carbon Column Observing Network)
    The Total Carbon Column Observing Network (TCCON) is a network of ground-based Fourier Transform Spectrometers that record spectra of the sun in the near-infrared. From these spectra, accurate and precise column-averaged abundances of atmospheric constituents including CO2, CH4, N2O, HF, CO, H2O, and HDO, are retrieved.
  • Island and Others
    Targeting coasts and islands, while avoiding bays and channels in order to increase the yield rate of spectra.

About parameter

  • xco2 : Column-averaged CO2 dry air mole fraction
    xco2 [ppmv]
  • ch4_column_idp : Column averaged CH4 mole fraction
    ch4_column_idp / retrieved_o2_column * 0.2095 * 1000000.0 [ppmv]
  • aerosol_total_aod : Retrieved total column-integrated aerosol optical depth for all aerosol types [wl=755nm]
  • aerosol_1_aod : Retrieved total column-integrated aerosol optical depth for aerosol type 1
    Aerosol type 1 may be type dust (DU), sulfate (SO), OC (Organic Carbon),black carbon (BC), or sea salt (SS).
  • aerosol_2_aod : Retrieved total column-integrated aerosol optical depth for aerosol type 2
    Aerosol type 2 may be DU, SO, OC, BC, or SS, and will be different from aerosol type 1.
  • aerosol_3_aod : Retrieved total column-integrated aerosol optical depth for aerosol type 3
    Aerosol type : Ice cloud
  • aerosol_4_aod : Retrieved total column-integrated aerosol optical depth for aerosol type 4
    Aerosol type : Water cloud
  • Fluorescence_at_reference(755nm)
    Solar-induced chlorophyll fluorescence (SIF) retrieved from TANSO-FTS at 755 nm. Negative retrieved value is set to zero in the graph.

About data extraction

In order to use long term trend data of the point of interest, the viewer pick up data within the circle of 10km radius.

But the following adjacent site, the viewer pick up within the circle of 1km or 2km radius.

[circle of 1km radius]

Osaka3, Osaka4
Bakersfield4 - 6
Boston4, Boston5, Greece4, Greece5

[circle of 2km radius]

Tokyo6, 8, 11 - 13
Bakersfield2, Bakersfield3
Aliso_Canyon2 - 4
Namibia1 - 3
Antarctica1 - 4
Beijing1 - 16
Shanghai1 - 13
Delhi1 - 16
Dhaka1 - 16
MexicoCity1 - 16
Istanbul1 - 16
Cairo1 - 15
CebuIsland1, 2
Sacramento(Rice Field), Sacramento(CA Capitol)
Karachi1 - 16

The primary pointing system, which had been used between launch and Dec. 2014, larger pointing offset of about 5km.

Therefore, some cases include nearby target points.

3. Citation


    Users of ACOS Data products should cite the following key ACOS references:
  • Wunch, D. et al., : The Total Carbon Column Observing Network, Phil. Trans. R. Soc. A, 369, 2087–2112, doi:10.1098/rsta.2010.0240, 2011a.
  • Wunch, D. et al., : A method for evaluating bias in global measurements of CO2 total columns from space, Atmos. Chem. Phys., 11, 12317-12337, doi:10.5194/acp-11-12317-2011, 2011b.
  • O' Dell, C. W. et al., : Preflight Radiometric Calibration of the Orbiting Carbon Observatory. IEEE Trans. Geosci. Remote Sens., 49 (6), 2438-2447,2011.
  • Crisp, D. et al.,: The ACOS CO2 retrieval algorithm - Part II: Global XCO2 data characterization, Atmos. Meas. Tech., 5, 687-707, doi:10.5194/amt-5-687-2012, 2012.
  • Frankenberg, C. et al.,: Prospects for chlorophyll fluorescence remote sensing from the Orbiting Carbon Observatory-2, Remote Sens. Environ., 147, 1-12, doi:10.1016/j.rse.2014.02.007, 2014.

5. Links

6. Acknowledgments

GHG Long term trend viewer was developed by JAXA/EORC. We would like to thank NASA/ACOS team, JAXA GOSAT project members and NIES GOSAT project members.