Color Scales

Use this Forum to find information on, or ask a question about, NASA Earth Science data.
Post Reply
dsgrimmer
Posts: 14
Joined: Fri Feb 24, 2023 6:00 pm America/New_York
Answers: 0

Color Scales

by dsgrimmer » Fri Feb 24, 2023 6:05 pm America/New_York

Hi! I'm looking into the differences between ocean color captured by MODIS Aqua and Seahawk Hawkeye but noticed that the color scale as shown on Ocean Color Web goes up to 60 mg/m^3, but in the SeaDAS program, the scale's limit is 20 mg/m^3. Which scale is accurate, and how come they are different? Please let me know, thanks so much!

Tags:

OB SeaDAS - xuanyang02
Subject Matter Expert
Subject Matter Expert
Posts: 644
Joined: Tue Feb 09, 2021 5:42 pm America/New_York
Answers: 1
Been thanked: 1 time

Re: Color Scales

by OB SeaDAS - xuanyang02 » Mon Feb 27, 2023 2:36 pm America/New_York

If you are talking about the Range for Color Manipulation, you can change the Max value as you need.
Attachments
Screen Shot 2023-02-27 at 2.36.59 PM.png
Screen Shot 2023-02-27 at 2.36.59 PM.png (102.72 KiB) Not viewed yet

gnwiii
Posts: 713
Joined: Fri Jan 29, 2021 5:51 pm America/New_York
Answers: 2
Has thanked: 1 time

Re: Color Scales

by gnwiii » Wed Mar 01, 2023 12:37 pm America/New_York

dsgrimmer wrote: Fri Feb 24, 2023 6:05 pm America/New_York the color scale as shown on Ocean Color Web goes up to 60 mg/m^3, but in the SeaDAS program, the scale's limit is 20 mg/m^3. Which scale is accurate, and how come they are different?

The choice of scale depends on the data. As noted by @xuanyang02 , you can make your own choice, although there are advantages to sticking with the ranges used for similar data in public archives.

Open ocean data averaged over time and at lower resolutions will have lower maximum values, so a 20 mg/m^3 upper bound misses very few pixels in global level-3 mapped data. Values over 20 are not unusual for individual level-2 files, particularly for coastal areas. Sometimes you want to highlight a feature such as an eddie and may want to chose a range that makes the feature easy to see in printed publications.
mg/m^3

dsgrimmer
Posts: 14
Joined: Fri Feb 24, 2023 6:00 pm America/New_York
Answers: 0

Re: Color Scales

by dsgrimmer » Fri Mar 03, 2023 12:12 pm America/New_York

Thanks so much for the feedback!

Post Reply