Search found 141 matches

by OB WebDev - norman
Fri Dec 08, 2017 3:31 pm America/New_York
Forum: Home
Question: Using GPT's WriteImage Operator to output GeoTIFF
Replies: 26

Using GPT's WriteImage Operator to output GeoTIFF

Here is a Mercator map of your region with length scales overlaidto help reinforce what Danny said about the projection not beingequal-area.  Only at 30 degrees North in the attached image are thepixels 1100x1100 meters.  North of that latitude pixels cover smallerareas while pixels cover ...
by OB WebDev - norman
Thu Dec 07, 2017 4:26 pm America/New_York
Forum: Home
Question: Using GPT's WriteImage Operator to output GeoTIFF
Replies: 26

Using GPT's WriteImage Operator to output GeoTIFF

Hi Simkins,I've been following this thread and think it might be useful if you coulddescribe exactly what input products you are using and what end resultyou are trying to achieve.  It sounds to me like you want to map level-2SST data to some sort of equal-area projection having pixels that...
by OB WebDev - norman
Mon Oct 02, 2017 1:55 pm America/New_York
Forum: Home
Question: L2 To L3
Replies: 2

L2 To L3

by OB WebDev - norman
Thu Sep 28, 2017 11:22 am America/New_York
Forum: Home
Question: Featured images
Replies: 13

Featured images

Hi Kim,The procedures I use to make the images that you may have seen vary a bit dependingon the scene in question, but there are some general similarities.  I'll share some ofthe process that went into making the current feature image in case that helps.The following bash script makes use ...
by OB WebDev - norman
Mon Sep 25, 2017 11:14 am America/New_York
Forum: Home
Question: Aqua MODIS Calcite product
Replies: 7

Aqua MODIS Calcite product

Hi Lionel,

I believe that SeaDAS should automatically apply the scaling.
Other packages would not necessarily be coded to do that.

Norman
by OB WebDev - norman
Mon Sep 25, 2017 9:24 am America/New_York
Forum: Home
Question: No data for PAR products L2
Replies: 4

No data for PAR products L2

Dear João,I downloaded your first example file and counted the number of no-data pixels.wget https://oceandata.sci.gsfc.nasa.gov/cgi/getfile/A2008114163500.L2_LAC_OC.nch5dump -d /geophysical_data/chlor_a -b -o chl A2008114163500.L2_LAC_OC.nc h5dump -d /geophysical_data/par -b -o par A20081143500.L2_...
by OB WebDev - norman
Fri Sep 22, 2017 4:23 pm America/New_York
Forum: Home
Question: Aqua MODIS Calcite product
Replies: 7

Aqua MODIS Calcite product

Hi Lionel,Are you applying the scale (slope) and offset (intercept) to the data?Compare, for example, August 2013 with August 2014.h5dump -a /pic/scale_factor A20132132013243.L3m_MO_PIC_pic_9km.ncHDF5 "A20132132013243.L3m_MO_PIC_pic_9km.nc" {ATTRIBUTE "scale_factor" {  ...
by OB WebDev - norman
Fri Sep 08, 2017 4:56 pm America/New_York
Forum: Home
Question: Do L2 SNPP SST data have a flag to distinguish day/night SST?
Replies: 9

Do L2 SNPP SST data have a flag to distinguish day/night SST?

Hi Jianke,Yes, "Mixed" means that the scene spans the day/night terminator.When I need to know the day/night status of a single pixel, I comparethe pixel's position vector with the solar position vector like this.    /* Get the solar position vector. */    l_sun(yea...
by OB WebDev - norman
Fri Jun 30, 2017 3:57 pm America/New_York
Forum: Home
Question: What's the default for dnm?
Replies: 1

What's the default for dnm?

Hi Bruce,Below are three specific examples.https://oceancolor.gsfc.nasa.gov/cgi/browse.pl?sub=level1or2list&per=MO&day=17136&sen=v0&n=70&s=50&w=-30&e=-5&dnm=Dhttps://oceancolor.gsfc.nasa.gov/cgi/browse.pl?sub=level1or2list&per=MO&day=17136&sen=v0&n=70&...
by OB WebDev - norman
Mon Jun 12, 2017 1:07 pm America/New_York
Forum: Home
Question: best suited sensor and algorithm for my work
Replies: 1

best suited sensor and algorithm for my work

It depends on the lake you are interested in.  Most South Florida lakes will be too smallto monitor with the standard ocean color sensors like MODIS and VIIRS.  Lake Okeechobeeis large enough, but you may need to develop your own bloom-detection algorithm becausethat lake does not meet all...