Mutual information forecasts for optimal adaptive sampling guidance

Analysis and Forecasts for 25 Jul 0000Z to 29 Jul 0000Z 2024, Issued 25 Jul 2024

We use mutual information (MI) forecasts between candidate observation locations and future variables of interest (target or verification variables, in this case the acoustic environment) to determine the most informative data locations. We use our MSEAS ensemble forecast to predict these fields.

For the MI fields that we show in the table below, the goal is to predict the candidate observations (types and locations) on July 25 that are the most informative about the sound-speed profiles at the 5 receiver/source locations on 00Z Jul 29, 2024

• The candidate point observations at each location in the domains are evaluated at 00Z on July 25, 2024 at the depths indicated in the table. The values measured are one of the following sets:
  • joint measurements of temperature and salinity
  • temperature only
  • salinity only
  • joint measurements of the u and v velocity components
• The target/verification variables are sound speeds at the 5 acoustic receiver/source locations (shown by green stars) at 2m, 50m, 200m, 500m, 1200m depths (i.e. 5 sound-speed profiles) at 00Z on July 29, 2024.

This MI forecast field confirms that for the sound speed in the acoustic area this past week, the inflows from the Nova Scotia slope water (filaments and eddies) and warm core ring filaments were important. It also shows that for these target sound speed profiles at that time in the acoustic region, velocity data is more informative at depth than T and S. Furthermore, T and S together is more informative than T or S alone.

Depth	TS	T	S	UV	Depth
surf					surf
-00050m					-00050m
-00200m					-00200m
-00500m					-00500m
-01200m					-01200m
Depth	TS	T	S	UV	Depth