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The National Aeronautics and Space Administration/ Goddard Space Flight Center's Nimbus Project Office, in collaboration with the NASA/GSFC Space Data and Computing Division, the NASA/GSFC Laboratory for Oceans and the University of Miami/Rosenstiel School of Marine and Atmospheric Science, have undertaken to process all data acquired by the Coastal Zone Color Scanner (CZCS) to Earth‐gridded geophysical values and to provide ready access to data products [Esaias et al., 1986]. An end‐to‐end data system utilizing recent advances in data base management and both digital and analog optical disc storage technologies has been developed to handle the processing, analysis, quality control, archiving and distribution of this data set. A more complete description of this system, which has been fully operational for the past 2 years, is in preparation. The entire Level‐1 data set (see Tables 1, 2) has been copied from magnetic tape to digital optical disc, and all data from the first 32 months (50% of the total scenes acquired, and covering the period November 1978 through June 1981) have been processed to Levels 2 and 3 and are now available for distribution. The remainder of the data set should be completed and released by fall 1989.

Experts working on behalf of international development organisations need better tools to assist land managers in developing countries maintain their livelihoods, as climate change puts pressure on the ecosystem services that they depend upon. However, current understanding of livelihood vulnerability to climate change is based on a fractured and disparate set of theories and methods. This review therefore combines theoretical insights from sustainable livelihoods analysis with other analytical frameworks (including the ecosystem services framework, diffusion theory, social learning, adaptive management and transitions management) to assess the vulnerability of rural livelihoods to climate change. This integrated analytical framework helps diagnose vulnerability to climate change, whilst identifying and comparing adaptation options that could reduce vulnerability, following four broad steps: i) determine likely level of exposure to climate change, and how climate change might interact with existing stresses and other future drivers of change; ii) determine the sensitivity of stocks of capital assets and flows of ecosystem services to climate change; iii) identify factors influencing decisions to develop and/or adopt different adaptation strategies, based on innovation or the use/substitution of existing assets; and iv) identify and evaluate potential trade-offs between adaptation options. The paper concludes by identifying interdisciplinary research needs for assessing the vulnerability of livelihoods to climate change.

Distributions of physical, biological, and chemical parameters in Florida Keys coastal waters seaward of the reef track were surveyed on September 9 to 13, 1993, as part of a coordinated multidisciplinary study of surface transport processes. A band of low-salinity water was observed along the shoreward side of the Florida Current over the downstream extent of the survey from Miami to Key West. Biological and chemical indicators within the band, together with its large volume, satellite imagery, and a surface drifter trajectory suggested the recent Mississippi River flood as the source. Introduction While the 1993 flooding itself received considerable popular attention [Mairson, 1994; Macilwain, 1993a, b] much less consideration has been given to its downstream effects. Upper layer salinities in the Florida Straits region are typically 36 or greater [Wennekens, 1959; Schmitz and Richardson, 1990]. Physical oceanographers have suspected the Mississippi River (MR) as a source of low-salinity water in the Gulf Stream and Florida Straits [Wennekens, 1959; Atkinson and Wallace, 1975; Maul, 1974] but were unable to confirn• their suspicions due to a lack of supporting data. As part of an ongoing regional program [Lee et al. , 1994], the physics, chemistry, and biology of these waters have been studied for the last 5 years. In this paper we relate physical, biological and chemical measurements in an anomalous low-salinity band to satellite advanced very high resolution radiometer (AVHRR) thermal imagery, Argos tracked surface drifter trajectories, and wind records from the Mississippi delta. Together, these data provide convincing evidence of entrainment of MR flood waters into the Gulf of Mexico Loop Current and subsequent transport through the Florida Straits and along the U.S. east coast on the shoreward side of the Gulf Stream.

[1] A 6-year time series of sea surface temperature fields derived from NOAA polar-orbiter AVHRR 5-day composites is used to estimate the lifetime, size, and trajectory of 43 warm-core rings shed by the Brazil Current at the Southwestern Atlantic region in a consistent fashion for the first time. Ring lifetimes range from 11 to 95 days, and are not bi-modal as is the case for the Gulf Stream anticyclones. Translational speeds range from 4.2 to 27.2 km/day with a mean value of 13.1 km/day. After formation, rings are mostly elliptical with a mean major radius of 126 ± 50 km and a minor radius of 65 ± 22 km. None of the rings seem to last more than four months in the region. An attempt to explore possible connections between ring shedding variability and the Antarctic Dipole is also addressed.