A land-based infrared (IR) camera is used to detect endangered Southern Resident killer whales in Puget Sound,
Washington, USA. The observations are motivated by a proposed tidal energy pilot project, which will be required to
monitor for environmental effects. Potential monitoring methods also include visual observation, passive acoustics, and
active acoustics. The effectiveness of observations in the infrared spectrum is compared to observations in the visible
spectrum to assess the viability of infrared imagery for cetacean detection and classification. Imagery was obtained at
Lime Kiln Park, Washington from 7/6/10-7/9/10 using a FLIR Thermovision A40M infrared camera (7.5-14μm,
37°HFOV, 320x240 pixels) under ideal atmospheric conditions (clear skies, calm seas, and wind speed 0-4 m/s). Whales
were detected during both day (9 detections) and night (75 detections) at distances ranging from 42 to 162 m. The
temperature contrast between dorsal fins and the sea surface ranged from 0.5 to 4.6 °C. Differences in emissivity from
sea surface to dorsal fin are shown to aid detection at high incidence angles (near grazing). A comparison to theory is
presented, and observed deviations from theory are investigated. A guide for infrared camera selection based on site
geometry and desired target size is presented, with specific considerations regarding marine mammal detection.
Atmospheric conditions required to use visible and infrared cameras for marine mammal detection are established and
compared with 2008 meteorological data for the proposed tidal energy site. Using conservative assumptions, infrared
observations are predicted to provide a 74% increase in hours of possible detection, compared with visual observations.
Over the past 4 years, we have developed and extensively deployed the Calibrated, InfraRed, In situ Measurement System, or CIRIMS, for at-sea validation of satellite-derived sea surface temperature (SST). The project is funded by the NASA EOS Validation Program for validation of SST from MODIS, the MODerate resolution Imaging Spectroradiometer, aboard the EOS Terra and Aqua satellites. The design goals include autonomous operation at sea for up to 6 months and an accuracy of ±0.1°C. One of the most challenging aspects of the design is protection against the marine environment. We use commercially available infrared pyrometers and a precision blackbody housed in a temperature-controlled enclosure. The sensors are calibrated at regular interval using a cylindro-cone target immersed in temperature-controlled water bath, which allows the calibration points to follow the ocean surface temperature. An upward-looking pyrometer measures sky radiance in order to correct for the non-unity emissivity of water, which can introduce an error of up to 0.5°C. As part of our design strategy, we have evaluated the use of an infrared transparent window to completely protect the sensor and calibration blackbody from the marine environment. A total of three units have been fabricated and deployed at sea for over 700 days since 1998. We give an overview of the design and report on the performance of the CIRIMS in comparison to the Marine-Atmosphere Emitted Radiance Interferometer (M-AERI) which is the primary in situ validation instrument for MODIS.
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