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Oceanic overflows are bottom-trapped density currents originating in semienclosed basins, such as the Nordic seas, or on continental shelves, such as the Antarctic shelf. Overflows are the source of most of the abyssal waters, and therefore play an important role in the large-scale ocean circulation, forming a component of the sinking branch of the thermohaline circulation. As they descend the continental slope, overflows mix vigorously with the surrounding oceanic waters, changing their density and transport significantly. These mixing processes occur on spatial scales well below the resolution of ocean climate models, with the result that deep waters and deep western boundary currents are simulated poorly. The Gravity Current Entrainment Climate Process Team was established by the U.S. Climate Variability and Prediction (CLIVAR) Program to accelerate the development and implementation of improved representations of overflows within large-scale climate models, bringing together climate model developers with those conducting observational, numerical, and laboratory process studies of overflows. Here, the organization of the Climate Process Team is described, and a few of the successes and lessons learned during this collaboration are high-lighted, with some emphasis on the well-observed Mediterranean overflow. The Climate Process Team has developed several different overflow parameterizations, which are examined in a hierarchy of ocean models, from comparatively well-resolved regional models to the largest-scale global climate models.

The Hudson River is used as a case study for stream ecology, focusing on the effects of water level fluctuations, seasonal changes and river discharge. Flood tides were found to have substantial mixing, as did spring tides, while ebb tides produced the weakest mixing.

The gene for cherubism, an autosomal dominant disorder perhaps related to tooth development and eruption and resulting in altered facial appearance and large amounts of fibrous tissue in the jaws, has been mapped to chromosome 4p16. A genomewide search has been carried out in a 3-generation family. Three other affected families were genotyped and mapped to the locus, which is across an interval of about 22 cM.