A Drift Card Study in Monterey Bay, California, September 1971 to April 1973: Annual Report, Part 4, 1973

Drift cards were released in Monterey Bay, California, to detect seasonal variations in the California Current system, and seasonal and diurnal wind variations in the immediate vicinity of the bay. About 23% of the cards were recovered, although the recovery rate varied from about 5% in the winter to about 60% in the late summer. Drift card speeds ranged from 1 to 8 km/day, in the winter and summer months respectively. Good agreement was observed between geostrophic current, wind, drogue, and drift card data, although drift cards were observed to be primarily wind driven. A weekend bias in drift card recoveries was observed for the entire period of study; however, it was less pronounced for those cards released during the summer months. Two bogus releases were used to estimate the discovery lag time, reported position accuracy, and longshore drift currents. Diurnal winds were observed during a 24-hour study, and indicated daily variations in the wind field may be as important as seasonal changes in moving surface water. The drift card speed was observed to be about 3% of the wind velocity, and 1 m/sec was estimated as the minimum effective wind. The wind factor, ranging from 2.2% to 4.0%, was used to estimate the actual paths of drift cards and to examine the role of diurnal winds in affecting surface water movement. (PDF contains 79 pages)

Improvements to Data Collection in Commercial Fisheries Using Electronic Reporting Methods: Cost/Efficiency and Implications for Use in Ecosystem Management.

Data have been collected on fisheries catch and effort trends since the latter half of the 1800s. With current trends in declining stocks and stricter management regimes, data need to be collected and analyzed over shorter periods and at finer spatial resolution than in the past. New methods of electronic reporting may reduce the lag time in data collection and provide more accurate spatial resolution. In this study I evaluated the differences between fish dealer and vessel reporting systems for federal fisheries in the US New England and Mid-Atlantic areas. Using data on landing date, report date, gear used, port landed, number of hauls, number of fish sampled and species quotas from available catch and effort records I compared dealer and vessel electronically collected data against paper collected dealer and vessel data to determine if electronically collected data are timelier and more accurate. To determine if vessel or dealer electronic reporting is more useful for management, I determined differences in timeliness and accuracy between vessel and dealer electronic reports. I also compared the cost and efficiency of these new methods with less technology intensive reporting methods using available cost data and surveys of seafood dealers for cost information. Using this information I identified potentially unnecessary duplication of effort and identified applications in ecosystem-based fisheries management. This information can be used to guide the decisions of fisheries managers in the United States and other countries that are attempting to identify appropriate fisheries reporting methods for the management regimes under consideration. (PDF contains 370 pages)

A mechanism for the link between solar-irradiance variations and regional precipitation

Although the mechanisms of climatic fluctuations are not completely understood, changes in global solar irradiance show a link with regional precipitation. A proposed mechanism for this linkage begins with absorption of varying amounts of solar energy by tropical oceans, which may aid in development of ocean temperature anomalies. These anomalies are then transported by major ocean currents to locations where the stored energy is released into the atmosphere, altering pressure and moisture patterns that can ultimately affect regional precipitation. Correlation coefficients between annual averages of monthly differences in empirically modeled solar-irradiance variations and annual state-divisional precipitation values in the United States for 1950 to 1988 were computed with lag times of 0 to 7 years. The highest correlations (R=0.65) occur in the Pacific Northwest with a lag time of 4 years, which is about equal to the travel time of water within the Pacific Gyre from the western tropical Pacific Ocean to the Gulf of Alaska. With positive correlations, droughts coincide with periods of negative irradiance differences (dry, high-pressure development), and wet periods coincide with periods of positive differences (moist, low-pressure development).

Time lag between catching and curing of fish and its influence on the finished product. 1. Mackerel

A study is made to determine the maximum permissible time lag both under iced and not iced storage conditions between the catching of mackerel (Rastrelliger kanagurta) and its curing, so that the quality of the finished product is within tolerable limits. Based on physical, chemical, bacteriological and taste panel studies the maximum time lag permissible is fixed as 8hrs under not iced condition and 3 days under iced condition. Icing of fish is also found to affect the tasting qualities of the finished product.