Development of regional future climate change scenarios in South America using the Eta CPTEC/HadCM3 climate change projections: climatology and regional analyses for the Amazon, S?o Francisco and the Paraná River basins     

Jose A. Marengo  Sin Chan Chou  Gillian Kay  Lincoln M. Alves  José F. Pesquero  Wagner R. Soares  Daniel C. Santos  André A. Lyra  Gustavo Sueiro  Richard Betts  Diego J. Chagas  Jorge L. Gomes  Josiane F. Bustamante  Priscila Tavares 《Climate Dynamics》2012,38(9-10):1829-1848

The objective of this study is to assess the climate projections over South America using the Eta-CPTEC regional model driven by four members of an ensemble of the Met Office Hadley Centre Global Coupled climate model HadCM3. The global model ensemble was run over the twenty-first century according to the SRES A1B emissions scenario, but with each member having a different climate sensitivity. The four members selected to drive the Eta-CPTEC model span the sensitivity range in the global model ensemble. The Eta-CPTEC model nested in these lateral boundary conditions was configured with a 40-km grid size and was run over 1961–1990 to represent baseline climate, and 2011–2100 to simulate possible future changes. Results presented here focus on austral summer and winter climate of 2011–2040, 2041–2070 and 2071–2100 periods, for South America and for three major river basins in Brazil. Projections of changes in upper and low-level circulation and the mean sea level pressure (SLP) fields simulate a pattern of weakening of the tropical circulation and strengthening of the subtropical circulation, marked by intensification at the surface of the Chaco Low and the subtropical highs. Strong warming (4–6°C) of continental South America increases the temperature gradient between continental South America and the South Atlantic. This leads to stronger SLP gradients between continent and oceans, and to changes in moisture transport and rainfall. Large rainfall reductions are simulated in Amazonia and Northeast Brazil (reaching up to 40%), and rainfall increases around the northern coast of Peru and Ecuador and in southeastern South America, reaching up to 30% in northern Argentina. All changes are more intense after 2040. The Precipitation–Evaporation (P–E) difference in the A1B downscaled scenario suggest water deficits and river runoff reductions in the eastern Amazon and S?o Francisco Basin, making these regions susceptible to drier conditions and droughts in the future.  相似文献   

An empirical solvus for CO₂-H₂O-2.6 wt% salt     

Eva Marie Hendel  Lincoln S Hollister 《Geochimica et cosmochimica acta》1981,45(2):225-228

The solvus in the system CO₂-H₂O-2.6 wt% NaCl-equivalent was determined by measuring temperature of homogenization in fluid inclusions which contained variable $\text{CO}{}_2\text{H}{}_2\text{O}$ but the same amount of salt dissolved in the aqueous phase at room temperature. The critical point of the solvus is at 340 ± 5°C, at pressures between 1 and 2 kbar; this is about 65°C higher than for the pure CO₂-H₂O system. The solvus is assymetrical, with a steeper H₂O-rich limb and with the critical point at mole fraction of water between 0.65 and 0.8.  相似文献   

Phase equilibria in fluid inclusions from the Khtada Lake metamorphic complex     

Lincoln S Hollister  Robert C Burruss 《Geochimica et cosmochimica acta》1976,40(2):163-175

The Khtada Lake. British Columbia, metamorphic complex consists of high grade amphibolite and metasedimentary units with development of gneiss, migmatite and homogeneous autochthonous plutons. Maximum metamorphic conditions are estimated to have exceeded 5 kbar and 700°C.Fluid inclusions in matrix quartz are highly variable in density and composition, ranging from apparently pure CO₂ (gas or liquid or both at room temperature) through CO₂ + H₂O ± CH₄ mixtures to inclusions which are entirely aqueous. They occur along cracks, in groups without planar features and as isolated inclusions. The latter and some which occur in groups, are interpreted to most nearly approximate, in density and composition, the fluids present during the peak of metamorphism.The density and fluid composition data are derived from direct observations of phase changes between ? 180 and + 380°C and from the application of published experimental data in the system CH₄-CO₂-H₂O-NaCl. The most dense, pure CO₂ inclusions indicate a pressure of entrapment at 5 kbar, if a temperature of 700°C is assumed. This is in close agreement with the minimum P-T estimates from the mineral assemblages. Methane was positively identified in inclusions in graphite-bearing specimens. Salt content is concluded to be about 5–6 wt% NaCl equivalent in the aqueous phase in both aqueous and CO₂ + H₂O inclusions. There is evidence of immiscible separation of CO₂-rich and H₂O-rich fluids at temperatures at least as high as 375°C.  相似文献   

First assessment of the highly contaminated harbour of Montevideo,Uruguay     

Danulat E  Muniz P  García-Alonso J  Yannicelli B 《Marine pollution bulletin》2002,44(6):554-565

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A case study of the abuse of science in sewage planning     

Lincoln C. Loehr  Eugene E. Collias 《Marine pollution bulletin》1984,15(12):439-443

A regional sewage system is under construction bordering southern Monterey Bay, California. It is replacing small treatment plants at Monterey, Seaside, Ford Ord, Marina and Salinas. The existing plants are mostly secondary, discharge no industrial wastes, and except for Salinas all discharge into the open ocean. The regional-system is the result of a zone of prohibition of waste discharge that was established in 1971. Justification for the zone was created by the Regional and State Water Boards several years after the zone was established. Our investigation of the evidence used to support the zone indicated that the water boards were clearly in error. The zone has been appealed through the Regional and State Boards and the courts. Over $100 000 000 (US) has already been spent on construction.  相似文献   

Old cannery wastes,a potential source of trace metals in the marine environment     

Lincoln C. Loehr  Eugene E. Collias 《Marine pollution bulletin》1983,14(10):392-394

High levels of lead and zinc have been measured in the California Mussel Mytilus californianus taken from southern Monterey Bay as part of the California State Mussel Watch programme. The levels of lead and zinc increase steadily from Cypress Point towards Cannery Row. The California State Water Resources Control Board (which funded but did not conduct the State Mussel Watch) has attributed the high levels to heavy metals contributed by sewage. The state mussel watch data reports have not considered the historic canning wastes from more than 30 canneries along Cannery Row as a possible source of trace metals. Leachates from old cannery wastes may be a major source of lead and zinc in mussels in southern Monterey Bay and must be considered in assessing any data from the State Mussel Watch programme.  相似文献   

Diatom assemblages from surface sediments of the Río de la Plata estuary,Uruguay     

Laura Perez  Ernesto Brugnoli  Pablo Muniz  Inés Sunesen  Eugenia A. Sar  Carolina Crisci 《新西兰海洋与淡水研究杂志》2018,52(3):383-397

The Río de la Plata estuary (RdlP) exhibits environmental gradients associated with the freshwater input and oceanic water intrusion. The aim of this study was to assess diatom species distribution in surface sediment samples related to such environmental gradients. The internal section of RdlP was dominated by Aulacoseira spp., Eunotia spp., Staurosirella martyi, Actinocyclus normanii and Thalassiosira baltica, indicatives of low salinity levels and high trophic conditions, associated with the riverine and estuarine regimes. The external section was dominated by Coscinodiscus radiatus, Thalassiosira spp., Paralia sulcata, Cyclotella striata, among other marine taxa, indicatives of high salinity and low trophic conditions, associated with the influence of the Southwestern Atlantic Ocean. Furthermore, the intermediate section presents a mixture of both diatom groups representing mixing conditions. The observed diatom species groups capture fairly well the RdlP environmental variability and can be reliably used for paleoenvironmental studies in this and other similar estuarine systems.  相似文献   

Polychaete Associations in a Subtropical
Environment (São Sebastião Channel,
Brazil): A Structural Analysis     

Pablo Muniz  Ana Maria S. Pires 《Marine Ecology》2000,21(2):145-160

Abstract. Analysis of polychaetes from 60 quantitative soft bottom samples (November 1993 – August 1994) from the São Sebastião Channel at 10 to 45 m yielded 126 species from a total of 12,003 individuals. The distribution of both the bottom sediment type and species was patchy. Abundance data were analysed with multivariate techniques and revealed a strong correlation between species and sediment variables. Polychaetes were more diverse, abundant and richer in species number in those sites with higher sandy fractions. On the other hand, sites where silt, clay and organic carbon predominated showed a poor annelid fauna. Here, pollution by the sewage discharge of a submarine pipe, the oil terminal activities and the clandestine oil tank washing have an important impact on the bottom fauna. Only little temporal variation in the composition of the polychaete associations was found during the study period.  相似文献   

Oxygen isotopic evidence for high‐magnitude,abrupt climatic events during the Lateglacial Interstadial in north‐west Europe: analysis of a lacustrine sequence from the site of Tirinie,Scottish Highlands          下载免费PDF全文

I. Candy  A. Abrook  F. Elliot  P. Lincoln  I. P. Matthews  A. Palmer 《第四纪科学杂志》2016,31(6):607-621

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Comparison of PCBs, organochlorine pesticides, and trace metals in cod liver from Georges Bank and Stellwagen Bank, USA and Canada     

Monosson E  Lincoln D 《Marine pollution bulletin》2006,52(5):591-597

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