Variability of rainfall from tropical cyclones in the eastern USA and its association to the AMO and ENSO

Tropical cyclone (TC) rainfall along the eastern USA exhibits a high degree of variability with the potential to produce precipitation amounts in excess of 100 % of the annual mean at locations ranging from the immediate coastline to hundreds of kilometers inland. However, the spatiotemporal distribution of TC rainfall variability has not yet been fully characterized for this region, particularly with regard to large-scale climate teleconnections (e.g., El Nino-Southern Oscillation (ENSO) and Atlantic multidecadal oscillation (AMO)). The objectives of this study are to (1) assess temporal variability and trends in TC rainfall since 1960, and (2) characterize the spatial variability of TC rainfall during varying AMO and ENSO regimes. Kendall tau-b analysis highlighted the presence of statistically significant positive trends in TC rainfall at a number of locations. Principal components analysis revealed that AMO exhibited significant linkages to TC rainfall in northern New England as well as along the US Gulf Coast, while ENSO was most strongly linked to TC variability in Texas. Results illustrate the varied nature of TC rainfall across the eastern USA and the complex linkages to large-scale climate mechanisms at interannual and decadal time scales.     

Climate change in the Paraná state,Brazil: responses to increasing atmospheric CO 2 in reference evapotranspiration

The hydrological variable evapotranspiration (ET) is challenging to estimate because it cannot be measured directly in natural environments (except in small plots). The uncertainties associated with the models used for its prediction have increased under climate change conditions. We studied the influence of stomatal resistance on ET estimates using the Penman-Monteith method as projected by three general circulation models in two emission scenarios (RCP4.5 and RCP8.5) for future climates throughout the twenty-first century (2010–2039, 2040–2069, and 2070–2099). We also investigated the probable ET rate changes in relation to the current (30 years average, 1980–2009) climate conditions for the Paraná state in the southern region of Brazil. The results were regionalized to help policymakers assess climate change impacts and design adaptation measures. ET increases of up to 15% were found in future climate conditions, which may lead to a significant increase in the water demand for agricultural crops. However, we believe that plant morphophysiological changes may occur under atmospheric CO2 enrichment conditions and that a possible reduction in stomatal conductance will result in lower ET increases than those obtained with the traditional Penman-Monteith method. When considering future climate scenarios, we propose the equation be adjusted to consider stomatal resistance as a function of CO2 concentrations.     

Foraging Behavior, Direct Interference and Habitat Use in Three Species of Flamingos (Phoenicopterus Chilensis, Phoenicoparrus Andinus and Phoenicoparrus Jamesi) in Mar Chiquita Lagoon, Córdoba, Argentina

正The Laguna Mar Chiquita,located northeast of the province of Córdoba in Argentina,is the only non-Andean place where three flamingo species regularly coexist in the southern part of South America.Two of these species,     

Biomarkers in croakers Micropogonias furnieri (Teleostei: Sciaenidae) from polluted and non-polluted areas from the Patos Lagoon estuary (Southern Brazil): evidences of genotoxic and immunological effects

Biomarkers of exposure and effect of pollutants were analyzed in croakers Micropogonias furnieri (Teleostei: Sciaenidae) captured in winter and summer in a polluted and in a non-polluted site at the Patos Lagoon estuary (Southern Brazil). Catalase and glutathione S-transferase activities (exposure biomarkers) and lipid peroxidation (effect biomarker) were analyzed in liver samples. Other two effect biomarkers were also studied: blood cells DNA damage (through comet assay and micronucleus test) and respiratory burst measurements. In a broad view, results point to an important seasonal variation of the biochemical biomarkers analyzed. However, data obtained clearly indicate that croakers collected in winter at the polluted site were subjected to a level of clastogenic agents sufficient to generate irreversible genetic damages (mutations) and impair the fish immune system.     

P-T conditions of earliest Late Cretaceous metamorphism in the Western Sonobari Complex,northwestern Mexico: tectonic implications

The Western Sonobari Complex in northwestern Mexico consists of metamorphosed rocks mostly derived from Palaeozoic (?) sedimentary and Mesozoic igneous protoliths. Rocks of this complex display amphibolite facies orogenic metamorphism, pervasive foliation, migmatization, and four folding phases. These features are ascribed to a contractional tectonic event with NNW–SSE shortening direction, which caused thrusting, thickening of the crust, and sinking of the lithological units. U–Pb geochronology of migmatitic leucosome bands indicates that peak metamorphic conditions were reached between ~93 and 89 Ma. Post-tectonic Late Cretaceous peraluminous aplite-pegmatite dikes transect the metamorphic foliation. Traditional thermobarometry in the metamorphic rocks yields average pressures and temperatures of 9.0–7.1 kbar and 745–663°C, typical of intermediate P/T Barrovian metamorphism. On the basis of its age and contractional character, the thickening event originating the metamorphism may be related to collision of the Alisitos island arc against crustal blocks of Mexico. Thermobarometric data of post-tectonic intrusives including Late Cretaceous granodiorite and Eocene gabbro indicate emplacement within an overthickened crust, while P-T conditions of post-tectonic dikes point towards an almost isothermal decompression path along the amphibolite facies field. Rock units of similar age and metamorphic character are discontinuously exposed from the Islas Marias offshore the Nayarit coast to the Peninsular Ranges batholith of Baja California, and even extend north into the Sierra Nevada batholith and the Sevier hinterland. This extensive belt of Barrovian metamorphic rocks thus provides a record of middle Cretaceous shortening and crustal thickening related to arc-continent collision followed by subduction resuming.     

Inspiring the next generation of scientists with their observations of quasars,black holes,Jupiter, and SETI with the Goldstone Apple Valley Radio Telescope,GAVRT

This paper describes a radio astronomy programfor schools, the Goldstone-AppleValley Radio Telescope,GAVRT. The GAVRT program is designed to bring the inspiration and enthusiasm to a younger generation of teachers and children who learn about science by doing real science, just as Iosif Shklovsky brought to an older generation.     

<Emphasis Type="SmallCaps">G</Emphasis>reen zero-valent iron nanoparticles for the degradation of amoxicillin

In the last years, it has been proven that zero-valent iron nanoparticles, including those produced using green methods, are efficient remediation agents for a wide range of target contaminants. However, apart from the known advantages of these green nanomaterials, the knowledge of how they act on distinct contaminants is not yet fully understood and requires further investigation. The objectives of this work were to study the degradation of a common antibiotic, amoxicillin, in water and in a sandy soil using green zero-valent iron nanoparticles (gnZVIs) as reductants and as catalysts for the Fenton reaction. It represents the first study of the use of gnZVI, as alternative for the zero-valent iron nanoparticles produced with sodium borohydride, for the degradation of amoxicillin. The results of the performed tests indicate that gnZVIs have the potential to be used in remediation processes. In both chemical tests, the gnZVI was able to degrade up to 100% of amoxicillin in aqueous solutions, using an amoxicillin/gnZVI molar ratio of 1:15 when applied as a reductant, and an amoxicillin/H₂O₂/gnZVI molar ratio of 1:13:1 when applied as a catalyst for the Fenton reaction. The soil tests showed that the required molar ratios for near complete degradation were higher in the reduction test (1:150) than in the gnZVI-catalyzed Fenton reaction (1:1290:73). This is possibly due to parallel reactions with the soil matrix and/or limitations of the reagents to reach the entire soil sample. The degradation efficiencies obtained in these tests were 55 and 97% for the reduction and catalyzed Fenton processes, respectively.     

Is there a common pattern of future gas-phase air pollution in Europe under diverse climate change scenarios?

Climate change alone influences future levels of tropospheric ozone and their precursors through modifications of gas-phase chemistry, transport, removal, and natural emissions. The goal of this study is to determine at what extent the modes of variability of gas-phase pollutants respond to different climate change scenarios over Europe. The methodology includes the use of the regional modeling system MM5 (regional climate model version)-CHIMERE for a target domain covering Europe. Two full-transient simulations covering from 1991–2050 under the SRES A2 and B2 scenarios driven by ECHO-G global circulation model have been compared. The results indicate that the spatial patterns of variability for tropospheric ozone are similar for both scenarios, but the magnitude of the change signal significantly differs for A2 and B2. The 1991–2050 simulations share common characteristics for their chemical behavior. As observed from the NO₂ and α-pinene modes of variability, our simulations suggest that the enhanced ozone chemical activity is driven by a number of parameters, such as the warming-induced increase in biogenic emissions and, to a lesser extent, by the variation in nitrogen dioxide levels. For gas-phase pollutants, the general increasing trend for ozone found under A2 and B2 forcing is due to a multiplicity of climate factors, such as increased temperature, decreased wet removal associated with an overall decrease of precipitation in southern Europe, increased photolysis of primary and secondary pollutants as a consequence of lower cloudiness and increased biogenic emissions fueled by higher temperatures.     

Aggradation and carbonate accumulation of Holocene Norwegian cold‐water coral reefs

Cold‐water coral ecosystems present common carbonate factories along the Atlantic continental margins, where they can form large reef structures. There is increasing knowledge on their ecology, molecular genetics, environmental controls and threats available. However, information on their carbo‐nate production and accumulation is still very limited, even though this information is essential for their evaluation as carbonate sinks. The aim of this study is to provide high‐resolution reef aggradation and carbonate accumulation rates for Norwegian cold‐water coral reefs from various settings (sunds, inner shelf and shelf margin). Furthermore, it introduces a new approach for the evaluation of the cold‐water coral preservation within cold‐water coral deposits by computed tomography analysis. This approach allows the differentiation of various kinds of cold‐water coral deposits by their macrofossil clast size and orientation signature. The obtained results suggest that preservation of cold‐water coral frameworks in living position is favoured by high reef aggradation rates, while preservation of coral rubble prevails by moderate aggradation rates. A high degree of macrofossil fragmentation indicates condensed intervals or unconformities. The observed aggradation rates with up to 1500 cm kyr^?1 exhibit the highest rates from cold‐water coral reefs so far. Reef aggradation within the studied cores was restricted to the Early and Late Holocene. Available datings of Norwegian cold‐water corals support this age pattern for other fjords while, on the shelf, cold‐water coral ages are reported additionally from the early Middle Holocene. The obtained mean carbonate accumulation rates of up to 103 g cm^?2 kyr^?1 exceed previous estimates of cold‐water coral reefs by a factor of two to three and by almost one order of magnitude to adjacent sedimentary environments (shelf, slope and deep sea). Only fjord basins locally exhibit carbonate accumulation rates in the range of the cold‐water coral reefs. Furthermore, cold‐water coral reef carbonate accumulation rates are in the range of tropical reef carbonate accumulation rates. These results clearly suggest the importance of cold‐water coral reefs as local, maybe regional to global, carbonate sinks.