Help for the Codiac search screens

• Geographic Coverage: is based on a box, defined by the four sides of the box. The negative sign indicates areas that are south and west of the earth's 0th degree of latitude and longitude.
  FORMAT: the format for entering latitudes and longitudes is decimal format: (+ or -) ddd.ddddd (trailing zeroes optional). For example -90.00, 90.0000, +90.00 are all valid entries. 10 degrees, 30 minutes, 0 seconds West longitude would be -10.5.

• Date: is the date that the data was recorded. The user can choose a single day by typing in the same date in both the Begin Date and End Date fields.
  FORMAT: The format for entering the date is yyyymmdd or yyyy/mm/dd. For example 19950202 and 1995/02/02 are both valid entries.

• Time: is the time of day that the data was recorded. The user can choose a single instant in time by typing in the same time in both the Begin Time and End Time fields.
  FORMAT: The format for entering the time is hh:mm:ss, where:
  
  hh is the UTC hour of observation in the range 00 to 23
  mm is the UTC minute of observation in the range of 00 to 59
  ss is the UTC second of observation in the range of 00 to 59
  
  
  For example, 00:00:00 is a valid entry denoting midnight, and 12:00:00 is a valid entry denoting noon.

• Output Format: allows you to select the format of the data file(s) that you receive from Codiac. A list of choices is available by entering the field. The list of available formats varies by dataset. If no choices are available, you will receive the file in its native format.

• Archive/Compression Method: allows you to select an archive and/or compression method for the files that are delivered to you. Compression utilizes non-destructive schemes for reducing the amount of data to be transferred over the network. When you select this option, compression is forced, except for certain common file extensions such as images and (previously) compressed files. Thus for some binary file types, compression may result in their sizes actually increasing. Some methods are also archive formats (e.g. Tar, Zip), bundling many files into one archive file. The Unix Tar only (.tar) option does not include compression while the Zip option does have forced compression. You must have the appropriate archive/compression software installed on your computer to decompress the data. If you are unfamiliar with compression, select "None".

• Email address: Codiac will send you an email when your data order is ready for pickup. Codiac will also send you an email containing reference metadata for the dataset and any additional README file for the dataset. Please review our privacy policy concerning your email address.

• Affiliation: We would like to know a little about our data users and ask you to supply your affiliation. This information was formerly determined based on email address, but that method is less valid as more people use third-party email providers.

• Clickable Image Map: allows you to select the the station that you want to browse by clicking on a map. The map contains a dot showing the location of each station that is available for the date/time that you selected. Modern graphical browsers support this feature. If you are using a textual browser (e.g. Lynx), or if the map does not display in your browser, choose "No" to view the available stations as a textual check list.

• Plot Type: allows you to select what type of browse plot that you wish to view. Note that some datasets have only one applicable plot type and so no user selection is required.

• Parameters: allows you to select which parameters you wish to browse. Note that some plot types (e.g. Skew-T) have a fixed set of browseable parameters and so no user selection is required. The parameters are as "Name [Units]"; and where applicable are also preceeded by their WMO BUFR code triples "(F XX YYY)".

• Output Image Format: allows you to select the format of the final (output) browse image. PNG (Portable Network Graphics) is a replacement for GIF, unencumbered by Unisys patents, and fully supported in modern applications. PDF is Adobe's latest document format, a successor to PostScript. Viewers for PostScript and PDF include GSview and products from Adobe. The PostScript output format is the best choice for zoom and printing/document-inclusion capabilities.

• Parameter/Station subset: allows you to subset the data files to contain only those parameters and/or stations that you desire.

• Event subset: allows you to subset the dataset based on an event name, such as RF01 (Research Flight 01) or a storm name.

• File subset: allows you to subset the dataset by choosing individual files.