NOAA AVHRR raster data

jdh wrote:

HRPT is a binary format, the official structure is described in https://www1.ncdc.noaa.gov/pub/data/satellite/publications/podguides/TIROS-N%20thru%20N-14/pdf/NCDCPOD2.pdf

A simplified overview is available http://www.sat.dundee.ac.uk/hrptformat.html

While it is possible to create a custom format reader in FME using the SDK, it's complicated (See https://knowledge.safe.com/articles/798/developing-a-new-format-readerwriter-with-the-fme.html for a starting place).

 

 

In FME you are probably better off using a python caller with either gdal or mpop

see http://www.pytroll.org/quickstart_avhrr.html for a mpop AVHRR tutorial

Personally I would check with the client as to the need to read HRPT data specifically, as opposed to the processed Sea Surface Temperature datasets in NetCDF like https://podaac.jpl.nasa.gov/dataset/AVHRR_SST_METOP_B-OSISAF-L2P-v1.0?ids=Sensor&values;=AVHRR&search;=Sea%20Surface%20Temperature

 

Hi jdh, i tried to open the NetCDF in FME 2017 data inspector and only got errors.

 

"not recognized as a supported file format"

 

were you able to open these SST NetCDF files from JPL in fme ?

 

 

Thanks Again,

 

 

Steve

 

 

goatboy wrote:

Hi jdh, i tried to open the NetCDF in FME 2017 data inspector and only got errors.

 

"not recognized as a supported file format"

 

were you able to open these SST NetCDF files from JPL in fme ?

 

 

Thanks Again,

 

 

Steve

 

 

What version of NetCDF did you download? the jpl offers both v3 and v4, but FME only supports up to V3.6.2 . I had no issue reading a version 3 nc file downloaded via the OPeNDAP Server.

 

 

jdh wrote:

What version of NetCDF did you download? the jpl offers both v3 and v4, but FME only supports up to V3.6.2 . I had no issue reading a version 3 nc file downloaded via the OPeNDAP Server.

 

 

perfect, thanks

 

 

jdh wrote:

What version of NetCDF did you download? the jpl offers both v3 and v4, but FME only supports up to V3.6.2 . I had no issue reading a version 3 nc file downloaded via the OPeNDAP Server.

 

 

Hi jdh, a couple more questions for you.... :-)

 

 

Using the jpl opendap server i select the variables i want (sea_surface_temperature). i leave nj and ni empty ??

 

To get data for x location select lat and long and provide the coordinates:

 

 

northernmost_latitude: -52.6559982 (nj)

 

southernmost_latitude: -71.1429977 (ni)

 

easternmost_longitude: 9.40999985 (nj)

 

westernmost_longitude: -54.0480003 (ni)

 

then export the netcdf v3 ... . is this the process you would go thru to export data for an area of interest you have ?

 

 

Also, sst units are kelvin, add 273 to get Celsius ? do i need to use the scale factor of 0.01 ? my results are strange temps ...

 

 

thanks steve

 

 

jdh wrote:

What version of NetCDF did you download? the jpl offers both v3 and v4, but FME only supports up to V3.6.2 . I had no issue reading a version 3 nc file downloaded via the OPeNDAP Server.

 

 

Those questions are probably better asked to I've only ever assisted students in obtaining the data, never actually used it myself.