A Caltech Library Service

Tropical methane emissions: A revised view from SCIAMACHY onboard ENVISAT

Frankenberg, Christian and Bergamaschi, Peter and Butz, André and Houweling, Sander and Meirink, Jan Fokke and Notholt, Justus and Petersen, Anna Katinka and Schrijver, Hans and Warneke, Thorsten and Aben, Ilse (2008) Tropical methane emissions: A revised view from SCIAMACHY onboard ENVISAT. Geophysical Research Letters, 35 (15). Art. No. L15811. ISSN 0094-8276.

[img] PDF - Published Version
See Usage Policy.

[img] Plain Text (readme.txt) - Supplemental Material
See Usage Policy.

[img] Postscript (Figure S1. Systematic spectral structures in the forward model impact on SCIAMACHY methane measurements) - Supplemental Material
See Usage Policy.

[img] PDF (Table S1. Additional modifications of water spectroscopic parameters) - Supplemental Material
See Usage Policy.

[img] PDF (Text S1. Text describing the cause of the spectroscopic interferences of methane retrievals with water vapor and modifications applied to the Bxl-Reims spectral database) - Supplemental Material
See Usage Policy.

[img] Plain Text (Tab-delimited Table 1) - Supplemental Material
See Usage Policy.


Use this Persistent URL to link to this item:


Methane retrievals from near-infrared spectra recorded by the SCIAMACHY instrument onboard ENVISAT hitherto suggested unexpectedly large tropical emissions. Even though recent studies confirm substantial tropical emissions, there were indications for an unresolved error in the satellite retrievals. Here we identify a retrieval error related to inaccuracies in water vapor spectroscopic parameters, causing a substantial overestimation of methane correlated with high water vapor abundances. We report on the overall implications of an update in water spectroscopy on methane retrievals with special focus on the tropics where the impact is largest. The new retrievals are applied in a four-dimensional variational (4D-VAR) data assimilation system to derive a first estimate of the impact on tropical CH_4 sources. Compared to inversions based on previous SCIAMACHY retrievals, annual tropical emission estimates are reduced from 260 to about 201 Tg CH_4 but still remain higher than previously anticipated.

Item Type:Article
Related URLs:
URLURL TypeDescription Information
Frankenberg, Christian0000-0002-0546-5857
Butz, André0000-0003-0593-1608
Houweling, Sander0000-0002-6189-1009
Warneke, Thorsten0000-0001-5185-3415
Additional Information:© 2008 American Geophysical Union. Received 18 April 2008; Revised 22 May 2008; Accepted 26 June 2008; Published 12 August 2008. CF is supported by the Dutch science foundation(NWO) through a VENI grant. We acknowledge John Burrows, PI of the SCIAMACHY instrument, for having initiated and realized the SCIAMACHY project. The Netherlands SCIAMACHY Data Center and ESA is greatly acknowledged for providing data and R. van Hees for having written the versatile NADC tools software package. We thank Ed Dlugokencky for providing NOAA ESRL CH4 data, Wouter Peters for providing CarbonTracker results and A. Segers, C. Schrijvers, and O. Tuinder for providing ECMWF data. We acknowledge the European Commission for supporting the 6th Framework Programme project HYMN (contract 037048), GEOMON (contract 036677) and GEMS-IP (contract SIP4-CT-2004-516099). We further acknowledge exchange of information within the EU 6th FP Network of Excellence ACCENT.
Funding AgencyGrant Number
European CommissionSIP4-CT-2004-516099
Issue or Number:15
Record Number:CaltechAUTHORS:20150508-150435686
Persistent URL:
Official Citation:Frankenberg, C., Bergamaschi, P., Butz, A., Houweling, S., Meirink, J. F., Notholt, J., . . . Aben, I. (2008). Tropical methane emissions: A revised view from SCIAMACHY onboard ENVISAT. Geophysical Research Letters, 35(15), n/a-n/a. doi: 10.1029/2008gl034300
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:57390
Deposited By: Joanne McCole
Deposited On:11 May 2015 22:06
Last Modified:09 Mar 2020 13:19

Repository Staff Only: item control page