GRIB2 PlugIn

[bdbcat]

jp...

OK, thanks. I will need to find some more WiFi bandwidth to get this GRIB. We are moving anchorage, so maybe later today, if I am lucky....

Dave

[rgleason]

Dave

Sorry about the inet connection. Most of these show no valid data or do not show data in Windows versions.
https://tgp-architects.com/files/ rguser rgpass
CMC_naefs-geps-raw-grib2.7z 15 mb

All except pressure and one other do not work.

[rgleason]

The grib2 in the above 7z are one instance of each type.

[rgleason]

PS also am using the most recent grib2 4.2.1 for windows Additionally the Arome grib2, does not load well. O is halted and frozen. I close O and reopen and the grib2 works. With what i believe is all data types available except possibly one overlay (i need to check this) Overlays to show you must zoom out and they show.

[rgleason]

With the "AROME_0.025_HP1_00H06H_201603071200.grib2" 55mb

The following data types work:
Wind
Wind gust
Pressure
Rainfall
Air Temp
CAPE
Wind Gust

What does not work is XXXXXX WAVES.


PS: And now I am a liar. It Wind Gust is working now, but not before. Very strange.

The grib file is still very hard to load with the same problems, - but 55mb what do I expect? It sure does not cover much territory for that amount of MB!

Basically the same as Ptizef's link
https://donneespubliques.meteofrance...T18%3A00%3A00Z

[rgleason]

Downloaded today's 31mb version
AROME_0.01_HP1_00H_201603101800.grib2

First time I tried opening it, it says No valid Data. Rather than get O frozen I hit the X.
Then reopen O, then click on the Grib Icon. It takes awhile for the grib to appear, but it does. This one shows everything but WAVES. ( Which is actually the same data the earlier grib2 did not work with.)

[bdbcat]

Rick...

On the Canadian Meteo Center GRIBs...

Most do not display, because they contain data of no interest to OCPN.
(aside: Maybe we should change the OCPN message to reflect the fact that some GRIB files may be readable, but have no data useful to OCPN)

a)PRMSL (Pressure, MSL) works OK
b) UGRD/VGRD (Wind speed/direction) will display if one concatenates the two GRIBv2 files (VGRD_TGL_10M and UGRD_TGL_10M) together.
c) TMP_TGL_2M (Air Temp) displays OK.

CAPE should display, but does not. I will investigate this.

GRIBv2 for OCPN will only display the variables listed in the pull-down choice list under GRIB->Settings. No more.

Once again we see that the large GRIB2 files from Meteo centers (other than NOAA GFS) to be of limited use to sailors as they are currently available "in the raw" online. Way too large for useful mobile download, and in the case of Canada, covering the entire world at a coarse 1 degree resolution....

But, hey, we are showing that OCPN GRIB2 can at least ingest them

Thanks for the thingie upload.
Dave

[rgleason]

Yes, we aren't interested in Soil Temperature, etc. and I do understand that our Grib2 reader only reads certain data types so unknown data types will not show.
Maybe others need a note.

My problem is I don't know what the abbreviations mean from various grib2 websites. Indeed, I have not yet found a decent website which has useful marine grib2 downloads in a sensible format. There is sooo much data available and we only need a smaller subset. I think a lot of the data comes from NOAA with some European websites which also offer good data, so those are probably be the best sources to start with. I am going to try using degrib and make a script that joins data in a certain small area.

I agree that Raw Grib is huge (as Bernie says) and probably not useful. -I'd rather just use grib1 as they are much smaller and faster. Is grib2 going to be a cumbersome animal with no useful download tools?

I tried some other files, from a variety of sources. Some work, some don't.
I'll compress I file with each type. Perhaps you'll want to try them. It is not very large.

[rgleason]

Maitai (qtVlm) suggested Current gribs from W4D
Index of /MyOcean
but I don't believe they are grib2. ..Might be useful to some though.

[rgleason]

Index of /MyOcean These gz files are grb when extracted by 7z. The grib2_pi actually reads the gz files, but all but the global.grb.gz file that I tested were just 2 dimensional (with no time). When extracted time became active. It is necessary to pick "All" to read these.

The global.grb.gz was pretty amazing. The whole globe's currents for 7 days at 7:00am and. 7mb

You could concatenate global currents up with Climatology and run Weather_routing....

[bdbcat]

jp...

I pushed a correction which should fix the linux segfault you reported recently. Might fix the Windows crash as well, although I could not reproduce it there.

I am looking at performance. The bottleneck is this: decoding embedded JPEG2000 streams using the Jasper library is very slow. Lots of google complaints about this, from many different apps and users.

We may need to investigate another library, like OpenJPEG....

Thanks
Dave

[Gilletarom]

Originally Posted by rgleason

Index of /MyOcean These gz files are grb when extracted by 7z. .....
You could concatenate global currents up with Climatology and run Weather_routing....

First :
The W4D MyOcean file are usable with the plugin Grib of O 4.2.
Second :
With this file, we can use it with Weather routing but, without a correct grib1 file for wind ... this is not really usable.

[Gilletarom]

But for many areas of the Channel, especially those of the Channel Islands (Jersey, Guernsey), the accuracy of the information contained in netCDF files ( "nc"), Copernicus, is much better

[Ptizef]

Dave

RE:
"I pushed a correction which should fix the linux segfault you reported recently. Might fix the Windows crash as well, although I could not reproduce it there."

I tested with Linux ... and I discovered a malformation in the date/time step
Before trying to open the file, I unselected all parameters and I closed "data at cursor position" dialog to ovoid any segfault

You can see that in the shot attached the completely inconsistent date/time steps. Of course, if I select a bad date/time, nothing works and I get several different segfaults
But If I select a good time/date, which are inside the bad ones, every thing
seems OK

I'll test with Windows as soon as possible, but I expect something similar

Jean Pierre

[Ptizef]

Dave

I tested last git in windows

At first I had a crash in "setRecordCurrentDate( )" function called by
"copyFirstCumulativeRecord()" function
I deactivated it ( in the general preferences of the plugin)
Then I opened the file but
1) I got the problem of bad date/time step (see screen shot)
2) in addition I got an assert failure (see second screen shot)

Jean Pierre