The TanSat mission: preliminary global observations

Liu, Yi; Wang, Jing; Lu, Yuexiang; Chen, Xi; Cai, Zucong; Yang, Dongxu; Yin, Zhicong; Gu, Shanqiang; Tian, Liqiao; Lu, Naimeng; Lyu, Daren

doi:10.1016/j.scib.2018.08.004

Cited by 103 publications

(62 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The Chinese Carbon Dioxide Observation Satellite Mission (Tan-Sat), which is similar to OCO-2, is designed to measure the atmospheric CO 2 content from space [31][32][33]. It was launched on December 21, 2016.…”

Section: Introductionmentioning

confidence: 99%

Retrieval of global terrestrial solar-induced chlorophyll fluorescence from TanSat satellite

Liu

et al. 2018

Science Bulletin

130

View full text Add to dashboard Cite

a b s t r a c tThe first Chinese Carbon Dioxide Observation Satellite Mission (TanSat), which was launched on December 21, 2016, is intended to measure atmospheric CO 2 concentration. The high spectral resolution (0.044 nm) and high SNR (360 at 15.2 mW m À1 sr À1 nm À1 ) measurements in the region of the O 2 -A band of the Atmospheric Carbon dioxide Grating Spectroradiometer (AGCS) module onboard TanSat make it possible to retrieve solar-induced chlorophyll fluorescence (SIF) from TanSat observations at the global scale. This paper aims to explore the potential of the TanSat data for global SIF retrieval. A singular vector decomposition (SVD) statistical method was employed to retrieve SIF using radiance over a micro spectral window ($2 nm) around the Fe Fraunhofer lines (centered at 758.8 nm). The global SIF at 758.8 nm was successfully retrieved with a low residual error of 0.03 mW m À1 sr À1 nm À1 . The results show that the spatial and temporal patterns of the retrieved SIF agree well with the global terrestrial vegetation pattern. The monthly SIF products retrieved from the TanSat data were compared with other remote sensing datasets, including OCO-2 SIF, MODIS NDVI, EVI and GPP. The overall consistency between TanSat and OCO-2 SIF products (R 2 = 0.86) and the consistency of the spatial patterns and temporal variations between the TanSat SIF and MODIS vegetation indices and GPP enhance our confidence in the potential and feasibility of TanSat data for SIF retrieval. TanSat, therefore, provides a new opportunity for global sampling of SIF at fine spatial resolution (2 km Â 2 km), thus improving photosynthesis observations from space.

show abstract

Section: Introductionmentioning

confidence: 99%

Retrieval of global terrestrial solar-induced chlorophyll fluorescence from TanSat satellite

Liu

et al. 2018

Science Bulletin

130

View full text Add to dashboard Cite

show abstract

“…Therefore, the simulated spectrum that is computed from the forward model needs to be converted into measurements using Stokes coefficients. The radiance measured from the TanSat ACGS can be expressed as follows [29]:…”

Section: Information Extraction From Tansat L1bmentioning

confidence: 99%

“…Bi et al validated OCO-2 observations with the Beijing ground-based FTS site, which provided a reliable method for TanSat validation [28]. For TanSat, Liu et al retrieved XCO 2 with the Institute of Atmospheric Physics, Chinese Academy of Sciences (IAPCAS) algorithm using nadir mode and validated the results with TCCON sites [29].…”

Section: Introductionmentioning

confidence: 99%

Retrieval and Validation of XCO2 from TanSat Target Mode Observations in Beijing

et al. 2020

View full text Add to dashboard Cite

Satellite observation is one of the main methods used to monitor the global distribution and variation of atmospheric carbon dioxide (CO2). Several CO2 monitoring satellites have been successfully launched, including Japan’s Greenhouse Gases Observing SATellite (GOSAT), the USA’s Orbiting Carbon Observatory-2 (OCO-2), and China’s Carbon Dioxide Observation Satellite Mission (TanSat). Satellite observation targeting the ground-based Fourier transform spectrometer (FTS) station is the most effective technique for validating satellite CO2 measurement precision. In this study, the coincident observations from TanSat and ground-based FTS were performed numerous times in Beijing under a clear sky. The column-averaged dry-air mole fraction of carbon dioxide (XCO2) obtained from TanSat was retrieved by the Department for Eco-Environmental Informatics (DEEI) of China’s State Key Laboratory of Resources and Environmental Information System based on a full physical model. The comparison and validation of the TanSat target mode observations revealed that the average of the XCO2 bias between TanSat retrievals and ground-based FTS measurements was 2.62 ppm, with a standard deviation (SD) of the mean difference of 1.41 ppm, which met the accuracy standard of 1% required by the mission tasks. With bias correction, the mean absolute error (MAE) improved to 1.11 ppm and the SD of the mean difference fell to 1.35 ppm. We compared simultaneous observations from GOSAT and OCO-2 Level 2 (L2) bias-corrected products within a ±1° latitude and longitude box centered at the ground-based FTS station in Beijing. The results indicated that measurements from GOSAT and OCO-2 were 1.8 ppm and 1.76 ppm higher than the FTS measurements on 20 June 2018, on which the daily observation bias of the TanSat XOC2 results was 1.87 ppm. These validation efforts have proven that TanSat can measure XCO2 effectively. In addition, the DEEI-retrieved XCO2 results agreed well with measurements from GOSAT, OCO-2, and the Beijing ground-based FTS.

show abstract

“…Most of the currently operating, planned and proposed instruments for passive CO 2 observations from space measure the reflected short-wave infrared (SWIR) solar radiation in several spectral windows covering the oxygen-A (O 2 A) band near 750 nm as well as the weak and strong CO 2 absorption bands near 1600 and 2000 nm, respectively, e.g. GOSAT (Greenhouse Gases Observing Satellite; Kuze et al, 2009Kuze et al, , 2016, OCO-2 (Orbiting Carbon Observatory-2; Crisp et al, 2004Crisp et al, , 2017, TanSat 10 (Liu et al, 2018), GOSAT-2 (Nakajima et al, 2012), OCO-3 (Eldering et al, 2019), MicroCarb (Buil et al, 2011), GeoCarb (Moore III et al, 2018), CarbonSat (Bovensmann et al, 2010;Buchwitz et al, 2013) and G3E (Geostationary Emission Explorer for Europe; Butz et al, 2015). These instruments and instrument concepts further rely on a comparatively high spectral resolution on the order of approx.…”

Section: Introductionmentioning

confidence: 99%

Towards space-borne monitoring of localized CO<sub>2</sub> emissions: an instrument concept and first performance assessment

Strandgren¹,

Krutz²,

Wilzewski³

et al. 2020

Preprint

View full text Add to dashboard Cite

Abstract. The UNFCCC (United Nations Framework Convention on Climate Change) requires the nations of the world to report their carbon dioxide (CO2) emissions. Independent verification of these reported emissions is a corner stone for advancing towards emission accounting and reduction measures agreed upon in the Paris agreement. In this paper, we present the concept and first performance assessment of a compact space-borne imaging spectrometer that could support the task of "monitoring, verification, reporting" (MVR) of CO2 emissions worldwide. With a single spectral window in the short-wave infrared spectral region and a spatial resolution of 50 x 50 m2, the goal is to reliably estimate the CO2 emissions from localized sources down to a source strength of approx. 1 MtCO2 yr-1, hence complementing other planned CO2 monitoring missions, like the planned European Carbon Constellation (CO2M). Resolving CO2 plumes also from medium-sized power plants (1–10 MtCO2 yr-1) is of key importance for independent quantification of CO2 emissions from the coal-fired power plant sector. Through radiative transfer simulations, including a realistic instrument noise model and a global trial ensemble covering various geophysical scenarios, it is shown that an instrument noise error of 1.1 ppm (1σ) can be achieved for the retrieval of the column-averaged dry-air mole fraction of CO2 (XCO2). Despite limited amount of information from a single spectral window and a relatively coarse spectral resolution, scattering by atmospheric aerosol and cirrus can be partly accounted for in the XCO2 retrieval, with deviations of at most 4.0 ppm from the true abundance for 68 % of the scenes in the global trial ensemble. We further simulate the ability of the proposed instrument concept to observe CO2 plumes from single power plants in an urban area using high-resolution CO2 emission and surface albedo data for the city of Indianapolis. Given the preliminary instrument design and the corresponding instrument noise error, emission plumes from point sources with an emission rate down to the order of 0.3 MtCO2 yr-1 can be resolved, i.e. well below the target source strength of 1 MtCO2 yr-1. Hence, the proposed instrument concept could be able to resolve and quantify the CO2 plumes from localized point sources responsible for approx. 90 % of the power plant CO2 emission budget, assuming global coverage through a fleet of sensors and favorable conditions with respect to illumination and particle scattering.

show abstract

The TanSat mission: preliminary global observations

Cited by 103 publications

References 50 publications

Retrieval of global terrestrial solar-induced chlorophyll fluorescence from TanSat satellite

Retrieval of global terrestrial solar-induced chlorophyll fluorescence from TanSat satellite

Retrieval and Validation of XCO2 from TanSat Target Mode Observations in Beijing

Towards space-borne monitoring of localized CO<sub>2</sub> emissions: an instrument concept and first performance assessment

Contact Info

Product

Resources

About

The TanSat mission: preliminary global observations

Cited by 103 publications

References 50 publications

Retrieval of global terrestrial solar-induced chlorophyll fluorescence from TanSat satellite

Retrieval of global terrestrial solar-induced chlorophyll fluorescence from TanSat satellite

Retrieval and Validation of XCO2 from TanSat Target Mode Observations in Beijing

Towards space-borne monitoring of localized CO&lt;sub&gt;2&lt;/sub&gt; emissions: an instrument concept and first performance assessment

Contact Info

Product

Resources

About

Towards space-borne monitoring of localized CO<sub>2</sub> emissions: an instrument concept and first performance assessment