Interpretation of Hydrographic Features Seen in the Waters Off Cape Cod.
Abstract
A study was conducted to determine the origin of features appearing in a Landsat image (1724-14472; 17 July 1974) of the waters off Cape Cod by multitemporal and multispectral analysis techniques. Acquisition of ancillary data supplemented imagery from five different sensors, including visible, near infrared, and microwave, representing fifteen discrete times over a five-year period. Digital data for the Landsat image was evaluated multispectrally. Various water reflectance models were applied to the digital data to determine whether features related to reflected light from the ocean bottom, turbidity, or surface reflectance. Parameters were estimated from historical data. Results of model calculations were compared with the observed radiances at several locations in the scene. Multitemporal analysis affirmed that the following detailed information can be determined from space imagery: Rapid rates of coastal change, possible uncharted shoals, and theorized surface manifestations of internal waves. In all cases multisensor imagery increased the reliability of the derived information. Multispectral analysis provided additional evidence for attributing variations of reflectance in deep ocean to the effects of surface reflection and also appears to be the primary cause of reflectivity of patterns over the shoal areas around Nantucket Island. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1981
- Accession Number
- ADA102343
Entities
People
- Charles Leonard Reed