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[Datastream #RHY-237530]: Satellite data available through Unidata?



Hi David,

re:
> Two follow-up questions, specifically about METEOSAT data access.
> 
> 1.  Do you know what the "latency" is for the "real-time" METEOSAT data
> you receive?  I don't know if you have ever checked or tested this, but
> essentially I am asking how much longer after the image is collected by
> a primary receiving station do you receive the file here in Boulder?

A couple of things related to Meteosat 9 data:

- I have never tried to determine what the latency is for Meteosat 9
  data via the NOAA ADDE server.  I typically access the data directly
  from an ADDE server at EUMETSAT.  Even though you would think that
  data available from EUMETSAT would be as close to realtime as possible,
  it isn't -- it is typically delayed by one to two hours.  The reason
  for this is that EUMETSAT does not consider their ADDE server to
  be "operational" in any sense.

  I will attempt to ascertain what, if any, delay is induced in the
  Meteosat 9 data through NOAA.

- the Meteosat 9 data is not "pushed" to us.  Instead, we have to
  initiate the contact with the NOAA or EUMETSAT ADDE servers.

> 2.  Can we make use of the "real-time" data [as in producing derived
> aviation products], or are there restrictions or approval required for
> real-time use?

This is a _very_ good question that has a two part answer:

- we can access and use the data as soon as it is available

- I am not sure if we can make products derived from the realtime
  data available immediately.  This is actually a tricky question:
  EUMETSAT has given permission to make "value added" products
  created from realtime Meteosat 9 data available to users on a
  case-by-case basis.  The best example I can offer off of the
  top of my head is for use in the PDA Animated Weather display
  (PAW) application from UW/SSEC:

  http://www.ssec.wisc.edu/data/paw/

  The author/developer of PAW, Russ Dengel, told me about a week
  and a half ago that he got permission to make the products
  he was creating for the PAW available before the standard
  24-hour delay that EUMETSAT imposes on redistribution of the
  data itself.  He "mused" that if the product being produced
  was different enough from the original data, that making it
  available without a 24-hour delay was OK.  I would not take
  his comment/musing as being EUMETSAT policy, however.

> I am pretty sure that there are restrictions on
> redistribution of the data itself,

Yes.  Meteosat 9 data is considered "realtime" until it is 24
hours old.  Before 24 hours, only the images from synoptic
reporting times (e.g., 0Z, 6Z, 12Z, and 18Z) can be redistributed.
After 24 hours, _all_ of the data can be redistributed.

Here is a portion of the guidance provided to me in December of
2001 in regard to Meteosat data by Silvia Castaner <address@hidden>
who was then (and probably still is) head of EUMETSAT legal services:

  Access to data by NOAA and its Affiliates is covered under an agreement
  between EUMETSAT and NOAA which was approved by the EUMETSAT Council
  and the US Government.  This Agreement establishes that NOAA may pass
  HRI Data to its "affiliates" and that these affiliates may include
  individually identified research institutes such as your Organisation.
  These affiliates may use the data for research and other NOAA Official
  Duty use but are not authorised to pass on the data on a realtime basis
  to third parties.  In this context realtime data is deemed to mean data
  which is younger than 24 hours.  Unfortunately your request to make
  available unencrypted delayed realtime data would not be in accordance
  with either the EUMETSAT Data Policy or the Agreement with NOAA.

> but we are wondering if we can start
> working with the data right away to produce derived products.  If there
> are restrictions on product generation, e.g. 24 hours,

There should not be any restrictions on producing the products as this
would fall under the category of research. The question is IF those
products could be (re)distributed outside of our organization before
they are at least 24 hours old.

> do you know what
> would be required to get approval to use the data right away?

A definitive answer can be gotten from the legal folks at EUMETSAT.
It may be wiser/quicker, however, to work through NOAA before
contacting EUMETSAT.  I say this based on my experience several
years ago when I was attempting to get permission from EUMETSAT
to make MSG (then Meteosat 8) data available in realtime to Unidata
educational institutions.  At some point in the back and forth
exchange of emails, I was contacted by a NOAA representative to
find out what our objective was.  Unknown to me at the time,
the head of EUMETSAT legal was BCCing NOAA on some of her responses
to me.  I was eventually advised by NOAA that I was not following
"proper" channels by interacting with EUMETSAT directly.

I am willing to send an email on your/RAL behalf to the NOAA
contact who was involved in my exchanges with EUMETSAT back
in 2001/2002.  He is not likely to still be in the same position
vis-a-vis Meteosat data, but he is likely to know who is.
Please let me know if you would like me to pursue this issue
on your behalf (i.e., to get you the name of the appropriate
contact).

> Thanks,

No worries.

Cheers,

Tom
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Ticket Details
===================
Ticket ID: RHY-237530
Department: Support Datastream
Priority: High
Status: Closed