<br><br><div class="gmail_quote">On Tue, Sep 27, 2011 at 6:05 AM, Stauffer Reto (UNI) <span dir="ltr"><<a href="mailto:reto.stauffer@student.uibk.ac.at">reto.stauffer@student.uibk.ac.at</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
Dear usergroup<br>
<br>
We would like to visualize some GFS products. Actually i get the data<br>
from the nomad servers "on demand" with<br>
<br>
'sdfopen <a href="http://nomad3.ncep.noaa.gov:9090/dods/gfs20110927/gfs_master_00z" target="_blank">http://nomad3.ncep.noaa.gov:9090/dods/gfs20110927/gfs_master_00z</a>'<br>
<br>
THE PROBLEM is that i have so much calls to the server that he kills the<br>
connection (after ~100 as written on the nomad3 servers page). Now there<br>
is also an option to load all the data with wget. For example the call is<br>
<br>
<a href="http://nomad3.ncep.noaa.gov:9090/dods/gfs20110926/gfs_master_00z.ascii?rh2m[14:28][46:46][22:22]" target="_blank">http://nomad3.ncep.noaa.gov:9090/dods/gfs20110926/gfs_master_00z.ascii?rh2m[14:28][46:46][22:22]</a><br>
<br>
It's the same "file/adress" but with the .ascii? option (selecting one<br>
variable "rh2m" here for certain timesteps [14:28] and for only one<br>
gridpoint (lon/lat 46/22). This works fine and i can create the<br>
ascii-file without any problem<br>
<br></blockquote><div><br></div><div>I don't think this will make any difference in so far access restriction is concerned. Using ASCII you likely just waste more resources than bringing binary data. If I recall well these files are stored in GRIB-2 at the server, so getting a single point may not save much because of the way compression is implemented (it may still need to read a full lat/lon layer in order to uncompress).</div>
<div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
BUT HOW TO READ those files with grads? Can i convert those files? Or<br>
open directly? Or create a controlfile?<br>
<br>
I read all possible hints and pages in the internet but i havnt found<br>
any solution until now.<br>
Does anyone have some experiences with that approach?<br>
<br>
Or is there another option not to run into the "server request restriction"?<br>
<br></blockquote><div><br></div><div>What many people do is to grab the binary GRIB-2 files with wget using plain http (not through the DODS interface). There are actually nice perl scripts to automate this, see</div><div>
<br></div><div> <a href="http://www.cpc.ncep.noaa.gov/products/wesley/fast_downloading_grib.html">http://www.cpc.ncep.noaa.gov/products/wesley/fast_downloading_grib.html</a></div><div><br></div><div>For reading the GRIB-2 files, see Wes' utilities:</div>
<div><br></div><div> <a href="http://www.cpc.ncep.noaa.gov/products/wesley/wgrib2/">http://www.cpc.ncep.noaa.gov/products/wesley/wgrib2/</a></div><div> <a href="http://www.cpc.ncep.noaa.gov/products/wesley/g2ctl.html">http://www.cpc.ncep.noaa.gov/products/wesley/g2ctl.html</a></div>
<div><br></div><div>and of course the grads documentation.</div><div><br></div><div> Good Luck,</div><div><br></div><div> Arlindo</div></div><div><br></div>-- <br>Arlindo da Silva<br><a href="mailto:dasilva@alum.mit.edu">dasilva@alum.mit.edu</a><br>