Located approximately 35 km to the east of oceanographic station GAK1, the Cape Fairfield transect is a set of fifteen closely spaced (~3.7 km) stations that run south from the northern Gulf of Alaska coast across the westward-flowing Alaska Coastal Current (ACC). The ACC is one of the primary surface flow features in the Gulf of Alaska and is characterized by a "wedge" of fresh water adjacent to the coast that sets up a cross-shore pressure gradient which then drives the coastal current flow westward. The first order modulation of the ACC and surrounding waters is due to the annual forcing cycles of fresh water discharge around the gulf periphery and the predominantly downwelling wind stress. In response to these forcings, the ACC wedge changes character in the steepness of the frontal isohalines, the magnitude of the frontal discontinuity, and the thermohaline properties of both the ACC and the ambient shelf waters.
The CTD data comes from 68 occupations of the C. Fairfield line on 46 cruises between the years 1980 and 2000. Cruises with multiple occupations were averaged into one synoptic sample; the one instance of two cruises within the same year and month were further averaged into one sample. The month of January has no samples and is the average of December and February. February has only one occupation; all other months have between two and seven samples.
ANNUAL CYCLE OF PHYSICAL PROPERTIES AT SELECTED DEPTHS: Monthly mean temperature, salinity, and density plots at various depths are presented. Data are averaged between stations CF3 and CF13 (approximately 8 and 45 km from shore). Note the varying amplitude and phase in the yearly cycle of all properties at different depths and the fall-winter temperature inversion.
CROSS-SECTION ANIMATIONS: The twelve monthly mean cross-sectional composites were oversampled to create a total of forty-eight frames. These animations are 750 to 900 KB in size. The vertical axis of the animations is pressure (db) and the horizontal axis is distance from shore (km).
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