Fellow NetCDFers,
While on leave, I recently had a chance to stop by two science events from
the European Space Agency Copernicus program.
I learned a lot, and thought I would share it. I very much welcome
correction or elaboration from anyone involved with the Copernicus program.
Starting with the Sentinel-3 spacecraft, all Copernicus ground data, from
level 1 up, are in NetCDF-4.
I was not previously aware of the scope and ambition of the Copernicus
system. There a snappy high-level description here:
https://www.youtube.com/watch?v=xcflQZJ5n88.
Here are some notes:
- Sentinel-1 and sentinel-2 missions are successful and on-going. But
who cares, since they don't use netCDF!
- NetCDF-4 was selected for all data starting with the Sentinel-3
mission, because of the ubiquity of netCDF combined with built-in data
compression. (Everyone loves that built-in data compression!)
- There are currently two Sentinel-3 spacecraft in polar orbit, 2 more
being built on the ground as replacements, so that there will always be 2
operational, for 15-30 years. (And this will be the case for all Sentinel
missions.)
- The sentinel-4 mission involves two instruments on the EUMESATs 3rd
generation satellites. There are two spacecraft in geocentric orbit and
more replacements standing by. (These are the EUMETSAT equivalent to NOAA's
GOES satellites.) These include a *sweet* hyper-spectral spectrometer.
- Sentinel-5P (for precursor) is a bonus spacecraft to fill a potential
instrument gap between existing instruments and the sentinel-5 satellites,
which are being built now for 2021 launch.
- Sentinel 6-10 missions are also planned, as is a gap-filling
Sentinel-6P mission.
- All Copernicus data are freely available in near real-time.
- As is generally the case, each generation of instrument sends lots
more data than the previous generation. So most(?) of their data holdings
are currently in netcdf-4.
- The Copernicus data stream is fast enough, and of high-enough
resolution, that it is being used in natural disaster situations (for
example to show which specific neighborhoods and houses are flooded).
- The data are also used in law enforcement, for environmental pollution
detection.
Copernicus is a very impressive program for Earth observation. The quality
and capability of the instruments, combined with the long-term support for
the program, will guarantee that Copernicus will become the backbone of a
lot of science.
I would very much welcome any comments from any Copernicus data users or
programmers about how netCDF-4 is working for you, and what are the
pain-points if any.
I would also be happy to share information on high-performance computing
with netCDF data, which can involved other packages like pnetcdf and PIO,
to give good parallel I/O performance.
Please contact me if you are using Copernicus data, and tell me about what
you are doing with it.
Thanks,
Ed Hartnett
