Estimating the Refractive Index Structure Parameter (Cn2) over the Ocean Using Bulk Methods
Frederickson, Paul A.
Davidson, Kenneth L.
Zeisse, Carl R.
Bendall, Charles S.
MetadataShow full item record
Infrared scintillation measurements were obtained along a 7-km path over San Diego Bay concurrently with meteorological measurements obtained from a buoy at the midpoint of the path. Bulk estimates of the refractive index structure parameter C2 were computed from the buoy data and compared with scintillation-derived C2 n n values. The bulk C2 estimates agreed well with the scintillation measurements in unstable conditions. In stable n conditions the bulk C2 estimates became increasingly higher than the scintillation values as the air–sea temperature n difference increased. This disagreement may be due to enhanced wave-induced mixing of the lower atmosphere that decreases the vertical temperature and humidity gradients in stable conditions from the assumed Monin– Obukhov similarity (MOS) theory forms, resulting in bulk C2 values that are too high. The bulk C2 estimates n n decrease rapidly when the absolute air–sea temperature difference approaches small positive values. These predicted decreases in C2 were not observed in either the path-averaged scintillation measurements or in single- n point turbulence measurements, indicating that bulk models for estimating scalar structure parameters based on mean air–sea scalar differences are not valid when the mean air–sea difference approaches zero. The authors believe that the most promising means toward improving the bulk C2 model is to obtain a better understanding n of the MOS functions over the ocean for a wide stability range, and particularly of the role of ocean waves in modifying near-surface vertical gradients and turbulence characteristics.
RightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
Showing items related by title, author, creator and subject.
Recent results on modeling the refractive-index structure parameter over the ocean surface using bulk methods Frederickson, Paul A.; Doss-Hammel, Stephen; Tsintikidis, Dimitris; Davidson, Kenneth (2005);Infrared scintillation measurements were obtained along a 7.2 km path over San Diego Bay, concurrently with mean meteorological and turbulence measurements obtained from a buoy located along the path. Bulk estimates ...
Haagensen, Brian Christian (Monterey, California. Naval Postgraduate School, 1973-06);Intensity scintillation in a laser beam at 0.63 micrometers in the marine boundary layer has been studied over a 4.3 kilometer horizontal path across Monterey Bay and also from shore to ship at San Nicolas Island. Optical ...
Cork, Bruce; Wenzel, William A.; Causel, Charles W. Jr. (American Physical Society, 1957-08-01);Protons of the internal circulating beam of the Bevatron were scattered in a polyethylene target. Both scattered and recoil protons were detected by scintillation counters at angles which define elastic proton-proton ...