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The Ocean Archive System searches our original datasets as they were submitted to us, not individual points or profiles. If you want to search and retrieve ocean profiles in a common format, or objectively analyzed fields, your better option may be to use one of our project applications. See: Access Data
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Linked index to information below: - Help Introduction - NOTE: When searching, please keep in mind, the Ocean Archive System (OAS) searches our original datasets as they were submitted to us, not individual points or profiles. If you want to search and retrieve ocean profiles in a common format, or objectively analyzed fields, your better option may be to use one of our project applications. On the OAS homepage you see a Basic Search free-form text page, which allows you to search for any term which may appear in an accession (a data packet sent to NODC for archving). If you search for “temperature”, your search will result in all accessions which mention the word temperature in their title, abstract, metadata, or have been tagged with temperature as a data type. To exclude a particular term from a search, precede the term with a minus sign like this: -salinity. For an exact match, enclose the term in double quotes like this: "Gulf of Mexico". For example, if you are searching for Gulf of Mexico data, but do not wish to receive data packets that contain the word salinity, enter “Gulf of Mexico”-salinity. Do not search for a data type using the word 'Data' (i.e., put 'chlorophyll' in the search box, not 'chlorophyll data'). For searching by date, it would be better to use the Advanced Search preferences page. However, if you wish to search on an exact date in the Free-form text box, use this format: yyyy-mm-dd. In addition to a free-text field on the OAS homepage, there is a feature of top-tabs where you can search the Authority Tables to locate search criteria. There are authority tables for: People, Projects, Institutions, Platforms, Seanames, Data Types, Instruments, and Observations. These table lookups can be very useful when you are not sure how NODC identifies the criteria that you need to use in your search. And, they also allow you to perform free-text searches. If you do not know the possible values for each of the top-tabs searches, you can leave the search fields blank and the system will pull up the full list of values when you click the Search button. Various pages throughout the OAS have a "Reports" link, which consists of standard queries that you may find useful. For example; you may wish to search all Oxygen records created in the last month. This "canned query" will be easier than using the Advanced Search, and is already set up. The Advanced Search page allows you to search the default settings of Title, Data type, Instrument type, Project, and Platform. To add or delete more search criteria, click on the Preferences link. You may select as few as one field (e.g., the Accession number, if you know the Accession Number of the collection that you desire), or you can select all fields. You do not have to use all of the fields that you choose. Once your preferences are selected, click Continue, and you’ll be brought back to the Advanced Search page, with all your new options. You can leave any field blank when clicking the Search button, and this will bring up the entire list of values for that option. Select multiple parameters in a selection box by using the normal convention of holding down the Control key and clicking additional values (or holding down the control key and clicking to deselect a value). You can select a range of values by selecting a value and then holding down the Shift key while clicking on a value above, or below the selected value. The pages have a Reset button that will change the selected fields back to the default or original selections. - NODC Accession Number - Text box - integer up to 7 digits Accession Numbers are assigned by NODC to identify individual data shipments or packets. Accession Number is a seven-digit field. Up until 1999, accession numbers were the two-digit year followed by a five-digit sequence number. For example, Accession Number 8300203 denotes the 203rd data shipment received in 1983. This practice was terminated in January 2000, and now accession numbers are simply an integer and have no intrinsic meaning. Sample Retrieval: Single Number: 8800123 selects information about this specific Accession Number. - Date Received - Text Box - date format Date received is the date on which NODC actually received the data from a particular source. This is not to be confused with the date on which data was collected or the starting date for a cruise. - Start Date - (earliest observation date) - Text Box - date format Start date is the date of the first or earliest observation within the data collection. This should not be confused with the date when NODC received the data (the Date received). Searching on Start date = 19990415 would identify all data sets where the earliest observation in the collection was April 15, 1999. This field is frequently used in conjunction with End date to form a range search. - End date - (latest observation date) - Text Box - date format End date is the date of the last or latest observation within the data collection. This should not be confused with the date when NODC received the data (the Date received). Searching on End date = 20010430 would identify all data sets where the latest observation in the collection was April 30, 2001. This field is frequently used in conjunction with Start date to form a range search. - Availability date - Keydate - Editdate - Text Boxes - date format Availability date is the date when NODC made the data collection available
to the public. [Note: When searching dates, you should mostly use the > or < operators, as placing in the exact date would be tough to match, unles you already know that it will match a dataset. Also, when entering dates, please check for leap years and make sure the day you have specified actually exists. For instance specifying the date as 19920431 or a date as 19890229 will result in zero records returned]. - Abstract - Text Box - ASCII text box The Abstract is a summary of the main points about the data accession. - Submitter - Selection Box - single choice The name of the scientist who submitted the data collection to NODC. The selection criteria is a drop down menu and the "=" operator is most frequently used. Only one name can be selected for a search. If you decide that you do not want to use this criteria, you can select the blank (first) line in the list. The != operator excludes. For example, to exclude accessions submitted by Firstname Lastname, you could select him and set use !=. - Geographical - Text Box - decimal degrees There are four fields associated with the geographic search: West boundary; East boundary; North boundary; South boundary. These are used to define a box with the West and North boundaries representing the upper left hand limit (north west) and the East and South boundaries representing the lower right hand limit (south east). By specifying search criteria as greater than the West boundary and less than the East boundary and greater than the North boundary and Less than the South boundary, you will select all data collections whose boundaries define a box, that when overlayed on the search box, have some portion of the box inside the search box. Remember, the records describe a collection of data (data sets) and not an individual point. There could be hundreds of different data formats in your selection. Therefore geographic retrievals in this system are a box searching a box. The records that are selected are those where any portion of the record box is inside the selection box. Consequently, the search usually returns data sets that cover a much larger region than what most users would expect. Even global data sets will show up in these searches. Also, though the default search type is '='. That is almost never useful. Leaving the search type as '=' will likely not find anything unless a data point falls right on that boundary. You will want to use an inequality, and consider the direction you are going carefully. - West Boundary - Text Box - decimal degrees - East boundary - Text Box - decimal degrees - North Boundary - Text Box - decimal degrees - South Boundary - Text Box - decimal degrees - Data type - Selection Box - multiple choice The Datatypes are the parameters that are contained in the collection. Since the assignment of data types to a data collection are based on the data format, sometimes even though the format contains a place to record an observation, the parameter may not have been sampled during that data collection effort . The selection criteria is in a drop down menu and you may select multiple parameters that will be or'ed together by using the normal convention of holding down the control key and clicking additional values (or holding down the control key and clicking to deselect a value). You can select a range of values by selecting a value and then holding down the shift key while clicking on a value above or below the selected value. - Observation type - Selection Box - multiple choice The Observation types describe how the data observations were collected. The values run the gamut from aerial photography through water chemistry, with time series and tows along the way. See the selection box on the search page. - Instrument type - Selection Box - multiple choice The Instrument types describe the intstrumentation that was used to collect the data, such as a CTD or an XBT. There are many, many values. See the selection box on the search page. - Sea areas - Selection Box - multiple choice The Sea areas are based on the International Hydrographic Bureau's Limits of Oceans and Seas. At present, only a fraction of the records contain entries for Sea area. If you search on Sea area and do not get a hit, it may be that the data you desire does not yet have the appropriate entry in the Sea area field. It does not mean that we don't have any data for that area. NODC is working to incorporate Sea area values in as many records as possible. Therefore, you may want to use Sea area in conjunction with latitude/longitude boundary searches to obtain all data from a certain geographical area. - Contributing projects - Selection Box - multiple choice Contributing projects are the names of the projects that were associated with the collection of the data. Some names are spelled out and some are entered as acronyms. You can use the top-tab link for Projects to look up the acronym based on a search of the project name. By leaving the fields blank, you can pull up every value for "Project". - Submitting Institution - Selection Box - single choice Submitting Institution is the institution that submitted the data collection to NODC. The Submitting Institution is not necessarily the institution that collected the data. Sometimes international organizations like the IOC will gather data from several sources and submit it to NODC. Most names are spelled out, but if you want to find the name that NODC uses for an acronym, use the top-tabs link for Institution. - Collecting Institution - Selection Box - multiple choice The Collecting Institution is the institution(s) that was responsible for collecting the data. Not necessarily the same as the Submitting Institution. - Platforms - Selection Box - multiple choice The Platforms are the names of the platforms that were used when collecting the data (e.g., a ship name or aircraft) - Title - Text Box - character string The Title is the title of the FGDC record for a data collection. Selection is usually done using a character string with the LIKE operator. - Metadata Level - On the Results pages, you will notice color-coding (and text equivalent) in the metadata column. This color-coding is an indication of the completion of our metadata records for that accession. In other words, because the metadata level is green doesn't mean that the metadata record is 'complete',
(i.e., that *all* the fields have values). It is an indication along a sliding scale, ranging from minimally complete to something just above the level of 'FGDC complete'. The metadata level is in no way an indication of the of validity of the data itself. It's mostly used internally to make sure our records are as complete as we can possibly make them.
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