U.S. Dept of Commerce/NOAA/PMEL/TAO

TAO Data Selection Help and Terminology

Data Selection procedure
TAO data selection terminology
Data type
Time-Series options
Variables
Pointer file options
Criteria for a test or demonstration

Data selection procedure

Use the clickable maps, type-in boxes and pull-down menus to specify your desired selection criteria (spatial or temporal, etc).
Click on the [SELECT] button to start the searching process.
All the selection criteria are optional.
If you do not specify any selection criteria, then all data will be selected (potentially tens of thousands of data files).
The results of the search will be a scrolling list of data files which met the selection criteria. From this scrolling list, you can select a data file for plotting, listing or downloading.

TAO data selection terminology

TAO data types fall into three categories. Note: Only Time Series are accessible here

Time Series Data Types - One dimensional data files indexed by time, such as those collected by instruments such as an anemometor, a current meter or a thermistor on a moored buoy.

Select or locate data by specifying one or more of the following selection criteria. Any of the criteria can be ignored. If no criteria are specified, then all data in the database will be selected, potentially tens of thousands of data files (not recommended).

Longitude range - to specify a range of of longitudes, enter the Westernmost and Easternmost longitudes as numbers between -180 and + 180. West is negative and East is positive.
- e.g., -110.5 is 110.5 degress West longitude, near the West coast of South America, 137 is 137 degrees East longitude, near the East coast of Indonesia, both in the Pacific Ocean.
Longitudes can also be entered with E or W to indicate the hemisphere.
- e.g., 110W, 110w, 110 W, 110 w and -110 are equivalent ways of specifying 110W, and 137E, 137e, 137 E, 137 e, and 137 are equivalent ways of specifying 137 degrees East longitude.
Latitude range - to specify a range of latitudes, enter two latitudes as numbers between -90 and 90. South is negative and North is positive.
- e.g., -10.5 is 10.5 degrees South latitude, and 10 is 10 degrees North latitude.
Latitudes can also be entered with N or S to indicate hemisphere.
- e.g., 10.5S, 10.5s, 10.5 S, 10.5 s, and -10.5 are equivalent ways of entering 10.5 degrees South latitude.
Date range - All data files which contain some data inside the specified time range will be selected.
Depth range - Depths in the ocean are entered as positive numbers, increasing downwards towards the bottom of the ocean. The surface of the ocean is 0, and 6000 meters deep in the ocean is 6000.
- For time series data, any time series from an instrument inside the specified depth range will be selected.
Month sub-range - If you have selected a multi-year date range, and you only want to choose data within certain months, i.e., the Northern hemisphere summer (Jun-Aug), then enter the subset of months to be searched.
Delta-t is the time interval between data points in Time-Series files. Select one of the values shown.
String(s) to locate in Filename - This search criteria is included for the convenience of scientists familiar with the TAO data files. File names often contain identifying information, such as Cruise identification for CTD data. This search criteria allows selection of data based on this identifying informaton. Enter one or more character strings, separated by spaces. Data with file names containing all the specified character strings will be selected.

Start the search by pressing the [Select] button (near the bottom of the screen).

Once data are selected, there are options for the individual time series, and other options for the entire set of selected data files.

Time-Series Options are operations on an individual time-series, such as making a plot or listing the data from a single time-series.
Variables - Most Time-Series All Data Sub-Types have only a single variable, like Barometric Pressure, Zonal Current, Meridional Wind, etc....
Pointer file options - An TAO pointer file is a list of data file names. Pointer file options are choices for different operations on a whole collection or list of data files, such as making a location plot, editing the pointer file, or downloading the pointer file to your local disk.

For a test or demonstration, try the following selection criteria (Longitude range 130E to 90W and latitude range 10S to 10N):

Data Type: Zonal Current
Longitude range: Westernmost = 130E and Easternmost = 90W
Latitude range: Northmost = 10S and Southmost = 10N
Time range: Jan 1 1980 - Dec 31 1997
Click "Select" at the bottom of the page
Click "GO" at the bottom of the page
--> Modify time range if desired. Click "Go" to make a time series plot

Go to the TAO Home Page

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