Today, the GNC-A transmission bandwidth has increased from 8.6 Mbps to 11.6 Mbps in preparation for GOES-16 imagery and products along with other product offerings.
INTELSAT-21, the satellite used to rebroadcast GNC-A data
When GOES-R data become available for public release (which is expected to happen next May), this will mean roughly a 6 fold increase in data coming down from the satellite to GNC-A receive stations.
It is essential that GNC-A users prepare for the increased data volume by determining whether their system can handle that amount of data or be prepared to selectively disable the new GOES-R channels: GOES-R-CMI-Imagery, GOES-R-GLM, and GOES-R-Level-2-Products sub-channels.
You could also use a script in your GNC-A system to regularly delete files depending on the capacity of your computer.
More info on the amount of data received may be found here.
The image above was generated using a GOES-16 simulated image sample downloaded from the GOES-R official webpage. To generate this plot, three freely available software were used: GDAL, GMT and IMAGEMAGICK. In the Tutorials section of this Blog, you will find a 114 page tutorial on the usage of these tools (using GNC-A data).
In this particular GOES-16 case, this simulated sample from the Channel 13 (10.35 um) was used. It is in NetCDF4, and has the same structure of the files that will be broadcasted through GNC-A.
The script below shows all the instructions used to generate the image above.
Basically, these are the functions performed by each software:
GDAL: Format conversion and image georeferencing.
GMT: Math, Color Palette, Projection, Shapefiles, Borders, Text and Legend
IMAGEMAGICK: Logo
# [GDAL] Converts the GOES-16 Channel 13 subdatased to NetCDF (format accepted by GMT)
gdal_translate -of netCDF -a_srs "+proj=geos +a=6378137. +b=6356752.31414 +lon_0=-89.5 +f=.00335281068119356027 +h=35786023. +sweep=x" -a_ullr -5434894.885056 5434894.885056 5434894.885056 -5434894.885056 HDF5:"OR_ABI-L2-CMIPF-M4C13_G16_s20161811455312_e20161811500135_c20161811500199.nc"://CMI Channel_13.nc -a_nodata -1
# [GDAL] Assigns a georeference to the image
gdalwarp -s_srs "+proj=geos +a=6378137. +b=6356752.31414 +lon_0=-89.5 +f=.00335281068119356027 +h=35786023. +sweep=x" -t_srs "+proj=latlong +datum=WGS84" Channel_13.nc Channel_13r.nc
# [GMT] Multiply the pixels by 0.039071999, sums 173.14999 and subtracts 273.15 to convert to Celsius.
grdmath Channel_13r.nc 0.039071999 MUL 173.14999 ADD -273.15 ADD = Channel_13.nc
# [GMT] Creates a color palette using the McIDAS-X IR4AVHRR6 color table, considering
# the lower limit as -103, the upper limit as 105, and intervals of 1 degree
makecpt -CIR4AVHRR6 -T-103/105/1 > C:\VLAB\CMI\palette.cpt
# [GMT] Chooses the plot size
gmtset PS_MEDIA A0
# [GMT] Projects the image, making the plot (post script format)
grdimage Channel_13.nc -JG-84.00/00.00/35775/0/0/0/0/0/10i -R-180/180/-90/90 -CC:\VLAB\CMI\palette.cpt -K > Channel_13.ps
# [GMT] Defines the border type ("plain", "inside" or "fancy")
gmtset MAP_FRAME_TYPE fancy
# [GMT] Defines the border thickness
gmtset MAP_FRAME_WIDTH 1.5p
# [GMT] Defines the border division thickness
gmtset MAP_TICK_LENGTH 0
# [GMT] Defines the size of the numbers in the border and legend
gmtset FONT_ANNOT_PRIMARY 9p
# [GMT] Defines the size of the scale and legend titles
gmtset FONT_LABEL 9p
# [GMT] Defines the characteristics of the grid primary line
gmtset MAP_GRID_PEN_PRIMARY 0.3p,white,-
# [GMT] Defines the border lat long characteristcs
pscoast -Ba5g10WSne -N1/0.0p,white -O -K -R -J >> Channel_13.ps
# [GDAL] Converts a shapefile to the GMT format
ogr2ogr -f "GMT" C:\VLAB\paises.gmt C:\VLAB\paises.shp
ogr2ogr -f "GMT" C:\VLAB\estados.gmt C:\VLAB\estados.shp
# [GMT] Adds the shapefiles to the final image.
psxy C:\VLAB\paises.gmt -W0.5p,black -R -J -O -K >> Channel_13.ps
psxy C:\VLAB\estados.gmt -W0.5p,black -R -J -O -K >> Channel_13.ps
# [GMT] Adds a text in the final image, according to the file "text_channel_13.txt"
pstext text_channel_13.txt -F+f+a+j -G0/0/0 -R -J -O -K >> Channel_13.ps
# [GMT] Adds a legend according to the specified color table
psscale -Dx0c/-0.5c+w25.1c/0.3c+h+e -CC:\VLAB\CMI\palette.cpt -B10:"Brightness Temperature [\260C]": -O >> Channel_13.ps
# [GMT] Converts the post script file to ".png"
psconvert -GC:\programs\gs\gs9.18\bin\gswin64c.exe Channel_13.ps -P -E300 -Tg -A -DC:\VLAB\CMI
# [ImageMagick] Adds the GNC-A Blog Logo the image
convert -composite C:\VLAB\CMI\Channel_13.png C:\VLAB\CMI\Blog_Logo.png -geometry +10+10 C:\VLAB\CMI\Channel_13.png
# Deletes all supporting files
del Channel_13.nc
del Channel_13r.nc
del Channel_13r.ps
del Channel_13.ps
del palette.cpt
In this link, you may download the additional files used to run this script (shapefiles, blog logo, color table and text).
NOVRA is a Canadian hi-tech company specialized in the transmission and reception of IP data over Digital Video Broadcast (DVB) channels using terrestrial and satellite communication links, the technology used by GEONETCast-Americas.
In some countries, where national manufacturers / resellers of antennas and LNB’s are available, the DVB receiver is the only piece of equipment that needs to be imported in order to assembly a GNC-A station (the ingestion software license is sent via e-mail).
Take a look on the list of resellers from IDC in the Americas. According to a recent contact from NOVRA’s Senior Sales Consultant to the Blog, they will be getting them on board to sell the NOVRA receivers.
Now that’s some great news! We’ll keep you informed.
As you may see in the Illustrated Product List, the GNC-A broadcast currently have GFS Model Products uploaded through MARN-El-Salvador, ISCS-GRIB1 and ISCS-GRIB2 channels.
0.5 degree GFS Model output (GRIB2 file) broadcasted by MARN opened in WINGRIDDS
In the MARN-El-Salvador channel, we have 2 model runs (00h and 12h UTC) for South,Central and part of North America, comprising 0~120h forecasts, for every 3 hours (160 files a day). The resolution is 0.5 degree.
0.5 degree GFS Model output (GRIB2 file) broadcasted by MARN opened in WINGRIDDS
0.5 degree GFS Model output (GRIB2 file) broadcasted by MARN opened in McIDAS-V, along with a GOES-13 IR GeoTIFF image (also broadcasted through GNC-A). Want to know how to do this? Check out our tutorials session!
In the ISCS-GRIB1 and ISCS-GRIB2 channels, we have global 1 degree resolution files in GRIB1 and GRIB2.
New 925mb data products (surface in areas with high elevations) are planned to be added to the ISCS-GRIB2 channel in 2017. These products will include HGT, TMP, RH, VVEL and U/V winds.
Please find below some samples generated using a few of the new 925mb data products:
As soon as these products are added to the system, we’ll release a new product list. We’ll keep you informed 🙂
In this particular GOES-16 case, 
GNC-A Blog 