This data set provides a high-precision and high-resolution record of atmospheric methane from the West Antarctic Ice Sheet (WAIS) Divide ice core WDC05A, spanning the years 1000 to 1800 C.E. The data include methane (CH4) concentration measurements and ice age chronology. Methane concentration data include mean sample depth, gas age, mean concentration, and concentrations from individual measurements, at a temporal resolution of approximately nine years. Ice chronology data include depth and ice age. Data are available via FTP, in Microsoft Excel (.xlsx) format.
Access to Ssalto/Duacs products
Ssalto/Duacs products use Jason-1, Envisat, GFO, ERS-1, ERS-2 and Topex/Poseidon data. File format is NetCDF, but the system also delivers images in Postscript format (only for gridded products).
Ssalto/Duacs system delivers global and specific regional products; combined datasets are also provided for high precision ... altimetry.
Near-Real Time products cover the 2001/08/22 - 2006/11/14 period. Delayed time data are available from October 1992.
Condition of access
Ssalto/Duacs NRTNear Real Time data are available via FTP: - with user identification and password for data <1 month , for scientific applications (GodaeGlobal Ocean Data Assimilation Experiment, seasonal/climate prediction centers) provided that a data use agreement is signed with Cnes. - or freely available for data older than one month (i.e NRT and DT data> 1 month)
CLS remains in charge of the commercial applications of these near-real time products.
For both DT and NRT products, the above acknowledgement has to be cited: "The altimeter products were produced by Ssalto/Duacs and distributed by Aviso with support from Cnes".