Data Services:Example3

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Advanced Example to get (or exclude) large Barker Ne ARO data from the CEDAR Database

The Barker Ne data from Arecibo (kindat code 2015 for example, or only Ne) can be very large because it is 20 sec data between ~55.1779 km and ~488.3853 km with an altitude interval of ~0.5791 km (ie 749 data points in each profile, since number_points=(488.3853-55.1779)/0.5791 + 1 = 748 + 1 = 749). This can result in MB of data for 1 day (about 37 MB/day). The system can go down trying to get this large amount of data, so here is an example of how to get what you want in smaller discrete chunks, and with ACF, drift, and Barker Ne data well separated.

What kind of data are available?

There are 3 (sometimes 4) basic data types (kindats) for Arecibo (ARO):

  1. Barker ne data, kindat=2015
  2. ACF data (Ne, Te, Ti, line-of-sight Vi), kindat=2010
  3. Drift data (Vi) in perpendicular and parallel directions, kindat 2011
  4. Vn neutral wind data estimates, kindat=2021 (sometimes)

You can get all the data at once, but it is often cleaner and less frustrating to get the data separately, since type 1, the Barker Ne, can bring the system to a halt because of its big size.

Please visit the Arecibo page.

(Can also get the data for each period plotted there also, but will get ALL the data for 2 days, which will also bring the system down!)

Getting the data and header info from the regular interface and adding constraints to the URL

  1. On web go to: http://cedarweb.hao.ucar.edu/wiki/
  2. Click on Data Services on the left
  3. Click on Get/Plot Data, which will take you to the VSTO data portal
  4. Click on the 'Data' tab at the top
  5. Click on 'Start by Instrument'
  6. Check 'Show Instrument Code' and click 'Reload' button
  7. Select '20 - Arecibo P.R. I.S. Radar [Radar > IncoherentScatterRadar]' and click the 'Next' button
  8. Select the year 2002
  9. For 2002, only April is available.
    • Select 04 (April) for the Month
  10. For Apr 2002, 15-17 are available.
    • Select day 17, then enter 1 for # Days and click 'Next'
  11. A page comes up with the data products listed (TAB FLAT ...) at the top, and the list of parameters below that.
  12. Click on INFO, and you will get all headers for 2010 (ACF Ne,Te,Ti), 2015 (Barker Ne), 2011 (Vi vector drifts), and 2021 (neutral E region winds) in a new browser window or browser tab.
  13. If you are not currently logged in you will be asked to do so. Once you log in you will see the INFO data.
  14. From here you can save the information as test, print it, etc..
  15. Close the browser window/tab and you should again see the page with the data products listed at the top and the list of parameters below.
  16. You COULD select a few of the parameters, but skip it. It is much safer to get everything. (NEVER SKIP ERROR BARS!)
  17. Select TAB (selecting 'FLAT' will give you much more data in 1 flat file where the time and 1-D parameters are repeated over and over again with the

changing 2-D parameters) Then the data will appear in the window. Software to read TAB or FLAT files is available in either a fortran or IDL code to read the data.

Let's change the date constraint. The normal date constraint is written as date(2002,417,0,0,2002,417,2359,5999) for data from 00:00:00.00 UT to 23:59:59.99 UT. To get 12 hour chunks, change the 2359,5999 to 1159,5999, or the 0,0 to 12,0 and then hit enter. With this new constraint you should see your data.