Oceanographic measurements on aerial surveys

Contact: James Churnside

ETL has developed an instrumentation package for use on the NOAA Twin Otters during visual surveys of marine mammals. It uses a suite of visible and infrared radiometers similar to those on satellites to measure sea surface temperature and chlorophyll concentration. This package was used by Dr. Rod Hobbs of the NMFS Alaska Fisheries Science Center during a survey of small cetaceans in Alaskan coastal waters in May and June. These data will allow the distribution of animals seen during the survey to be placed in the context of oceanographic features. This should help us understand why the animals are where they are, how they might respond to changes in oceanographic conditions, and how they might best be protected from any adverse effects of change.

The data provided are available from satellite instruments, but the data obtained from satellite have two problems for this application. First, they do not see through clouds, while the aircraft often flies below clouds and does see the surface. Second, the spatial resolution is poor, which often means that data near the coast must be eliminated because of land within a pixel. We are currently processing the data. By the second deployment next year, we hope to have a system to process the data closer to real time.