A linear method for the retrieval of sun-induced chlorophyll fluorescence from GOME-2 and SCIAMACHY data
Global retrievals of near-infrared sun-induced chlorophyll fluorescence (SIF) have been achieved in the last few years by means of a number of space-borne atmospheric spectrometers. Here, we present a new retrieval method for medium spectral resolution instruments such as the Global Ozone Monitoring...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2015-06-01
|
| Series: | Atmospheric Measurement Techniques |
| Online Access: | http://www.atmos-meas-tech.net/8/2589/2015/amt-8-2589-2015.pdf |
| _version_ | 1811316825609207808 |
|---|---|
| author | P. Köhler L. Guanter J. Joiner |
| author_facet | P. Köhler L. Guanter J. Joiner |
| author_sort | P. Köhler |
| collection | DOAJ |
| description | Global retrievals of near-infrared sun-induced chlorophyll fluorescence (SIF)
have been achieved in the last few years by means of a number of space-borne
atmospheric spectrometers. Here, we present a new retrieval method for medium
spectral resolution instruments such as the Global Ozone Monitoring
Experiment-2 (GOME-2) and the SCanning Imaging Absorption SpectroMeter for
Atmospheric CHartographY (SCIAMACHY). Building upon the previous work by
Guanter et al. (2013) and Joiner et al.
(2013), our approach provides a solution
for the selection of the number of free parameters. In particular, a backward
elimination algorithm is applied to optimize the number of coefficients to
fit, which reduces also the retrieval noise and selects the number of state
vector elements automatically. A sensitivity analysis with simulated spectra
has been utilized to evaluate the performance of our retrieval approach. The
method has also been applied to estimate SIF at 740 nm from real
spectra from GOME-2 and for the first time, from SCIAMACHY. We find a good
correspondence of the absolute SIF values and the spatial patterns from the
two sensors, which suggests the robustness of the proposed retrieval method.
In addition, we compare our results to existing SIF data sets, examine
uncertainties and use our GOME-2 retrievals to show empirically the
relatively low sensitivity of the SIF retrieval to cloud contamination. |
| first_indexed | 2024-04-13T11:56:06Z |
| format | Article |
| id | doaj.art-a86ad694b4eb48c88f516f0b62d403f9 |
| institution | Directory Open Access Journal |
| issn | 1867-1381 1867-8548 |
| language | English |
| last_indexed | 2024-04-13T11:56:06Z |
| publishDate | 2015-06-01 |
| publisher | Copernicus Publications |
| record_format | Article |
| series | Atmospheric Measurement Techniques |
| spelling | doaj.art-a86ad694b4eb48c88f516f0b62d403f92022-12-22T02:47:54ZengCopernicus PublicationsAtmospheric Measurement Techniques1867-13811867-85482015-06-01862589260810.5194/amt-8-2589-2015A linear method for the retrieval of sun-induced chlorophyll fluorescence from GOME-2 and SCIAMACHY dataP. Köhler0L. Guanter1J. Joiner2Institute for Space Sciences, Freie Universität Berlin, Berlin, GermanyInstitute for Space Sciences, Freie Universität Berlin, Berlin, GermanyNASA Goddard Space Flight Center, Greenbelt, MD, USAGlobal retrievals of near-infrared sun-induced chlorophyll fluorescence (SIF) have been achieved in the last few years by means of a number of space-borne atmospheric spectrometers. Here, we present a new retrieval method for medium spectral resolution instruments such as the Global Ozone Monitoring Experiment-2 (GOME-2) and the SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY). Building upon the previous work by Guanter et al. (2013) and Joiner et al. (2013), our approach provides a solution for the selection of the number of free parameters. In particular, a backward elimination algorithm is applied to optimize the number of coefficients to fit, which reduces also the retrieval noise and selects the number of state vector elements automatically. A sensitivity analysis with simulated spectra has been utilized to evaluate the performance of our retrieval approach. The method has also been applied to estimate SIF at 740 nm from real spectra from GOME-2 and for the first time, from SCIAMACHY. We find a good correspondence of the absolute SIF values and the spatial patterns from the two sensors, which suggests the robustness of the proposed retrieval method. In addition, we compare our results to existing SIF data sets, examine uncertainties and use our GOME-2 retrievals to show empirically the relatively low sensitivity of the SIF retrieval to cloud contamination.http://www.atmos-meas-tech.net/8/2589/2015/amt-8-2589-2015.pdf |
| spellingShingle | P. Köhler L. Guanter J. Joiner A linear method for the retrieval of sun-induced chlorophyll fluorescence from GOME-2 and SCIAMACHY data Atmospheric Measurement Techniques |
| title | A linear method for the retrieval of sun-induced chlorophyll fluorescence from GOME-2 and SCIAMACHY data |
| title_full | A linear method for the retrieval of sun-induced chlorophyll fluorescence from GOME-2 and SCIAMACHY data |
| title_fullStr | A linear method for the retrieval of sun-induced chlorophyll fluorescence from GOME-2 and SCIAMACHY data |
| title_full_unstemmed | A linear method for the retrieval of sun-induced chlorophyll fluorescence from GOME-2 and SCIAMACHY data |
| title_short | A linear method for the retrieval of sun-induced chlorophyll fluorescence from GOME-2 and SCIAMACHY data |
| title_sort | linear method for the retrieval of sun induced chlorophyll fluorescence from gome 2 and sciamachy data |
| url | http://www.atmos-meas-tech.net/8/2589/2015/amt-8-2589-2015.pdf |
| work_keys_str_mv | AT pkohler alinearmethodfortheretrievalofsuninducedchlorophyllfluorescencefromgome2andsciamachydata AT lguanter alinearmethodfortheretrievalofsuninducedchlorophyllfluorescencefromgome2andsciamachydata AT jjoiner alinearmethodfortheretrievalofsuninducedchlorophyllfluorescencefromgome2andsciamachydata AT pkohler linearmethodfortheretrievalofsuninducedchlorophyllfluorescencefromgome2andsciamachydata AT lguanter linearmethodfortheretrievalofsuninducedchlorophyllfluorescencefromgome2andsciamachydata AT jjoiner linearmethodfortheretrievalofsuninducedchlorophyllfluorescencefromgome2andsciamachydata |