Mary Jo Richardson

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Recent current velocity measurements across the lower continental rise of Nova Scotia show a deep equatorwardflow with speeds (maximum, 73 centimeters per second) among the highest recorded for the deep sea. Silicate measurements indicate that this flow usually consists of southern-source (Antarctic) bottom water. These measurements confirm the existence of(More)
The primary means of determining particulate organic carbon (POC) concentrations in aquatic environments is by filtering from water bottles or by in situ filtration with pumps and analyzing the filters. The concentrations measured by these two methods, however, can differ by a factor of 1.2–5 in temperate waters, and by factors as large as 200 in cold,(More)
As part of the North Atlantic Bloom Experiment (NABE), CTD/transmissometer profiles were made on two cruises at 47°N, 20°W in spring 1989 to quantify the increase in particles during a phytoplankton bloom in relationship to biophysical forcing factors. Water samples were filtered to obtain particle mass concentrations for calibration of beam attenuation(More)
As part of the U.S. JGOFS EqPac process study beam c profiles were obtained during two time-series occupations of the equator at 14o " W ('IT008 and lTO12). CTD/transmissometer profiles were routinely performed three times a day, roughly at dawn, noon, and just prior to sunset. Additionally, 'die1 experiment' days of intensive profiling (every 3 h) were(More)
The near-bottom sedimentation rates were measured by placing cylindrical sediment traps 10 m above the sea floor on each of six moorings deployed between 4100 and 5100 m along a transect across an energetic deep-sea current in the HEBBLE area centered at 40°N, 63°W on the Nova Scotian Rise. Sedimentation rates above the sea floor were monitored with(More)
Several SeaWiFS products have been compared with shipboard data to assess the possibility of using remote sensing to estimate particulate organic carbon (POC) concentration in surface waters. Transmissometer data were collected during six South Atlantic Ventilation Experiment (SAVE) hydrographic expeditions conducted between November 1987 and March 1989(More)
Four sediment traps of radically different design were deployed in the Santa Barbara Basin for approximately 45 days. The measured fluxes ranged from 370 to 774 g m-2 yr I for the different designs. These values lie within flux measurements previously determined for the basin. Compared to the 25-year record (920 g m-2 yr-i), however, all fluxes determined(More)
The standing stock of particulate organic carbon (POC) was determined during "ve cruises in the Ross Sea in 1996 and 1997 and compared with primary production of carbon measured in short-term C-incubations and the #ux of organic carbon collected in moored sediment traps. POC concentrations were estimated from transmissometer pro"les that were calibrated(More)
The e!ects of changes in the mixed-layer depth on the distribution of particulate organic carbon (POC) and chlorophyll a were examined in the Arabian Sea during the Northeast Monsoon (January and December), Spring Intermonsoon (February}March), and Southwest Monsoon (July and August) of 1995. POC distributions were derived from pro"les of beam attenuation(More)