How to perform a search with Polaris?

You can use this interface to get file-level, on-the-fly browse access to selected NSIDC data sets and immediate access to the data as it is archived at NSIDC. You can also reformat, reproject, and subset the data on-the-fly, with live downloads available via the data queue as soon as your request is completed.

How to perform a data search:

Initial Polaris screen

1. From the Search tab, use the Geospatial field to narrow your search to a specific geospatial area. If you do not make a geospatial selection, the default is to search the whole globe. If you limit your search to a specific area, the search will return all available data that intersect with your selected area.

To modify the geospatial fields, use the Choose View option buttons North Polar, Global, or South Polar to change the view of the map. The North and South polar view maps work well for searches that cross or are near the poles. The global view map works well for searches that cross the equator.

2. After selecting a map view, modify the geospatial fields to specify your area of interest, or use your mouse directly on the map to draw a bounding box by clicking and dragging.

The North Polar and South Polar map views use corner points in lat/lon pairs to define the area of a box. You only need to define the upper left and bottom right corners in lat/lon pairs (the white text boxes) to create your area. The other two corners (the grey text boxes that do not allow you to enter text) are created automatically based on the box drawn.

The Global map view uses lat/lon bounds (northernmost, southernmost, westernmost, and easternmost) to define the area of a box. If you use the mouse to draw the area on the map, the fields are filled in automatically, based on the box drawn.

To reset the map, click on the Reset Map & Selection button.

3. Use the Date Range and Intra-annual Range fields to refine your search by selecting a temporal range. If you do not specify a temporal range, all available time periods will be searched.

Use the Date Range field to refine your search to data between start and end dates. Either enter dates manually in the text boxes (yyyy-mm-dd), or click on the calendar icons to choose your dates.

Use the Intra-annual Range field to refine your search to a specific time period within the Data Range field, either by choosing the day of year (ddd) or a month/day combination (mm-dd).

Example: If you enter a date range of 1990-01-01 to 1992-01-01 and an intra-annual range of 150 to 175, your search will return data for the following temporal ranges:

  • Days 150-175 in 1990
  • Days 150-175 in 1991

Polaris search screen

4. Use the Data Sets and Variables lists to restrict your search to a specific data set and variable combination. If you do not make a selection, then all available data sets and/or variables will be searched.

Example: If you select only Brightness Temperature, your search will look for any data sets with Brightness Temperature fields.

5. Select the data set you would like to look at.

6. Click on the Search button.

Results

 Polaris results screen