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81.
Norway     
This section of a two-part report is introduced by Drs Ehler and Basta of NOAA. It deals with operational discharges of oil from marine transportation sources and was compiled by Virgil F. Keith, Robert A. Mondor and Nannette J. Goldberg, of Engineering Computer Optecnomics, Inc., Annapolis, MD 21401, and Charles N. Ehler, Daniel J. Basta and Thomas F. LaPointe of the Ocean Assessments Division, Office of Oceanography and Marine Services, National Ocean Service, National Oceanic and Atmospheric Administration, Rockville, MD 20852. Charles Ehler is the Acting Chief of the division; Daniel Basta is the Acting Chief of its Strategic Assessment Branch. The second part of the report on predicting surface transport of pollutants in the Gulf will form next month's Viewpoint.  相似文献   
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Summary Natural aerosols over the ocean are usually in electrical equilibrium. Aerosols in cities are hardly ever in electrical equilibrium. Aerosols over land are frequently not in equilibrium even though distant from any obvious source of contamination.Calculations are given of the time required to reach equilibrium which would lead one to expect the conditions encountered over the ocean and in cities. Some speculations are made on the lack of equilibrium over land.
Zusammenfassung Natürliche Aerosole über dem Ozean sind gewöhnlich in elektrischem Gleichgewicht. Aerosole in Städten sink kaum jemals im elektrischen Gleichgewicht. Aerosole über Land sind häufig nicht im Gleichgewicht, selbst wenn sie weit weg von irgendwelchen offenkundigen Quellen der Verunreinigung sind.Es werden Berechnungen der Zeit, welche für die Erreichung des Gleichgewichtes erforderlich ist, gegeben. Einige überlegungen über das Nichtvorhandensein elektrischen Gleichgewichtes über Land werden mitgeteilt.
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The health impacts of simultaneous exposure to multiple adverse environmental factors are of concern in the United Kingdom. UK-wide indicators exist, but context-specific finer resolution measures are lacking. An environmental deprivation index was developed for 398 neighborhoods (average population = 760) in a Scottish council area, including measures of air pollution, noise pollution, traffic environment, undesirable land uses, and crime. Adverse environmental conditions were related to ill health in the region and implicated in wider socioeconomic health inequalities. The results suggest an independent role for environmental deprivation in explaining poor health and health inequalities.  相似文献   
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Book reviews     
WETLANDS: a threatened landscape (Institute of British Geographers Special Publication Series No.25) edited by M. Williams. 17 × 24 cm, x + 419 pp. Blackwell, Oxford 1993 (first published 1990) (ISBN 0 631 19199 2) $65.00 (soft).

GUIDE TO MAPS IN SOUTH AUSTRALIAN PARLIAMENTARY PAPERS 1852–1971 (Historical Geography Monograph No.7) edited by J. McQuilton. 21 × 29 cm, 178 pp. Australian Reference Publications, Melbourne 1994 (ISBN 0 9587876 4 6).

THE EMERGENCE OF BIOREGIONALISM IN THE MURRAY‐DARLING BASIN by J.M. Powell. 21 × 30 cm, 105 pp. Murray‐Darling Basin Commission, Canberra 1993. (ISBN 1 875209 212) $20.00 (soft).  相似文献   

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The subduction and export of subantarctic mode water (SAMW) as part of the overturning circulation play an important role in global heat, freshwater, carbon and nutrient budgets. Here, the spatial distribution and export of SAMW is investigated using Argo profiles and a climatology. SAMW is identified by a dynamical tracer: a minimum in potential vorticity. We have found that SAMW consists of several modes with distinct properties in each oceanic basin. This conflicts with the previous view of SAMW as a continuous water mass that gradually cools and freshens to the east. The circulation paths of SAMW were determined using (modified) Montgomery streamlines on the density surfaces corresponding with potential vorticity minima. The distribution of the potential vorticity minima revealed “hotspots” where the different SAMW modes subduct north of the Subantarctic Front. The subducted SAMWs follow narrow export pathways into the subtropical gyres influenced by topography. The export of warmer, saltier modes in these “hotspots” contributes to the circumpolar evolution of mode water properties toward cooler, fresher and denser modes in the east.  相似文献   
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