SOCAT QC2 -- Frequently Asked Questions

The SOCAT collection:

1. What cruise datasets are included in the SOCAT collection?
• 1851 public cruise datasets are currently included, covering all oceans and ranging in time from the 16^th of November, 1968 until the 31^st of December, 2007.
2. What are the agreed-upon SOCAT QC flags?
• The SOCAT QC flags are cruise-specific, and are the flags from the Wannikof Scale from the SOCAT-2 Paris meeting (A, B, C, D, F). The flags EXCLUDE and SUSPEND have also been used for cruises to exclude them from the collection entirely, or to temporarily suspend from QC. Only cruises with flags of A, B, C, or D are included in the current public release.
• WOCE flags are applied to single data points in a collection. A WOCE flag of 2 means ‘good’, a WOCE flag of 3 means ‘questionable’, and a WOCE flag of 4 means ‘bad’.
3. How was fCO2 computed from cruises that reported CO2 concentrations by other means?
• The procedure by which the variable fCO2_rec (the recomputed fCO2) was obtained is described in http://www.socat.info/Uniform_format_surface_fCO2_database.pdf.   The variable fCO2_source, which is also found in the consolidated SOCAT cruise data product http://cdiac.ornl.gov/ftp/oceans/SOCATv1.5/, contains an integer (1-14) that indicates which pathway was used for the calculation at each data point.  
4. How should I cite the SOCAT collection in a publication?
• Pfeil, B., A. Olsen, D.C.E. Bakker, et al. (2011) A uniform, quality controlled, Surface Ocean CO₂ Atlas (SOCAT). Earth System Science Data (in preparation).
5. How should I cite the Gridded SOCAT product in a publication?
• Pfeil, B., Olsen, A., Bakker, D.C.E. et al. (2011) A uniform, quality controlled, Surface Ocean CO2 Atlas (SOCAT). Earth System Science Data (in preparation).
• Sabine et al. (2011) Gridding of the Surface Ocean CO₂ Atlas (SOCAT). Earth System Science Data (in preparation).

Using the LAS system:

1. What is the SOCAT LAS?
• The SOCAT LAS exists as a visualization tool for the SOCAT data collection. It offers maps and property-property plots of cruise data, subset tools for downloading portions of the dataset, and tools to keep track of the second order quality control that is being performed by SOCAT members.
2. What types of output can LAS provide?
• Through LAS you can make maps and property-property plots of arbitrary selections of data. Data selections may be based upon constraints such as cruise ID, ship name, season, QC flag, space-time region, etc. Small or large subsets of the data can be downloaded as well. New functionality is constantly being added, and you can request new features, comment on current ones, and file bug reports via email to mailto: submit@socat.info
3. How can I look at the data from a particular cruise or a list of particular cruises?
• From the map page, use a global map, check the "cruise ID" constraint, and select all the cruises from which you would like to see data. Click "Update" to update the map and subset those cruises from the collection. Click "Download Data" to download all the data from those cruises in a tab delimited text file.
• From the table of cruises, click a link in the "Cruise File" column to see that cruise data.
• Download a zip file of all cruises, a zip file of any of the gridded data sets, or the original cruise files using the "Download Data" link on the SOCAT start page (http://www.socat.info/)
4. How can I get SOCAT data into ODV?
• Data downloaded using the "Download Data" button on the map page or table of cruises page is in the same format ODV uses to import and export tables of data.
• The raw data files in SVN are also in ODV export format and can be imported into ODV using the import tool.
5. How can I get SOCAT data into Matlab?
• TBD
6. How can I ask to see just a particular cruise by name? (or a list of cruises by name?)
• On the map page, use the cruise or ship name constraints to restrict your search. Groups can be selected by holding the shift or control keys and clicking the cruises or ships that you are interested in.
7. How do I obtain the metadata for a particular cruise?
• On the table of cruises page, click on the metadata link accompanying the cruise you are interested in. Not all cruises have metadata available on the web.
8. How do I look for outliers in the SOCAT cruise collection?
• The best way to look for outliers is to use the property-property plots. Narrow your selection using the map page and then click the "Property-property plot" button.
• If the total number of cruises you are plotting is under 200, unique icons will appear. Check one or more icons to single out those cruises, or leave all check boxes blank to show all.
9. How can I see the locations where data are missing?
• Missing data will show up in black on the map page.
• The amount of missing data is documented in the annotations on top of all plots.