Space-time variability of the Amazon River plume based on satellite ocean color     

Gustavo S.F. Molleri  Evlyn M.L.de M. Novo  Milton Kampel 《Continental Shelf Research》2010,30(3-4):342-352

Satellite ocean color images were used to determine the space-time variability of the Amazon River plume from 2000–2004. The relationship between sea-surface salinity (SSS) and the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) absorption coefficient for dissolved and detrital material (a_dg) (r²=0.76, n=30, rmse=0.4) was used to identify the Amazon River plume low-salinity waters (<34 psu). The plume's spatial information was extracted from satellite bi-weekly time series using two metrics: plume area and plume shape. These metrics identified the seasonal variability of plume dimensions and dispersion patterns. During the study period, the plume showed the largest areas from July to August and the smallest from December to January. The mean annual amplitude and the mean, maximum and minimum plume areas were 1020×10³ km², 680×10³ km², 1506×10³ km² and 268×10³ km², respectively. Three main shapes and dispersion pattern periods were identified: (1) flow to the northeastern South American coast, in a narrow band adjacent to the continental shelf, from January to April; (2) flow to the Caribbean region, from April to July; and (3) flow to the Central Equatorial Atlantic Ocean, from August to December. Cross-correlation techniques were used to quantify the relationship between the plume's spatial variability and environmental forcing factors, including Amazon River discharge, wind field and ocean currents. The results showed that (1) river discharge is the main factor influencing plume area variability, (2) the wind field regulates the plume's northwestward flow velocity and residence time near the river mouth, and (3) surface currents have a strong influence over river plume dispersion patterns.  相似文献   

GEOGRAPHY IN THE DOMINICAN REPUBLIC*     

Gustavo A. Antonini  Jose J. Hungria 《The Professional geographer》1988,40(1):96-100

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Radio relics in a cosmological cluster merger simulation     

Matthias Hoeft  Marcus Brüggen  Gustavo Yepes 《Monthly notices of the Royal Astronomical Society》2004,347(2):389-393

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Ocean heat content for tropical cyclone intensity forecasting and its impact on storm surge   总被引：1，自引：0，他引：1  

I.-I. Lin  Gustavo J. Goni  John A. Knaff  Cristina Forbes  M. M. Ali 《Natural Hazards》2013,66(3):1481-1500

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Stratospheric ozone depletion: a key driver of recent precipitation trends in South Eastern South America     

Paula L. M. Gonzalez  Lorenzo M. Polvani  Richard Seager  Gustavo J. P. Correa 《Climate Dynamics》2014,42(7-8):1775-1792

On a hemispheric scale, it is now well established that stratospheric ozone depletion has been the principal driver of externally forced atmospheric circulation changes south of the Equator in the last decades of the 20th Century. The impact of ozone depletion has been felt over the entire hemisphere, as reflected in the poleward drift of the midlatitude jet, the southward expansion of the summertime Hadley cell and accompanying precipitation trends deep into the subtropics. On a regional scale, however, surface impacts directly attributable to ozone depletion have yet to be identified. In this paper we focus on South Eastern South America (SESA), a region that has exhibited one of the largest wetting trends during the 20th Century. We study the impact of ozone depletion on SESA precipitation using output from 6 different climate models, spanning a wide range of complexity. In all cases we contrast pairs of model integrations with and without ozone depletion, but with all other forcings identically specified. This allows for unambiguous attribution of the computed precipitation trends. All 6 climate models consistently reveal that stratospheric ozone depletion results in a significant wetting of SESA over the period 1960–1999. Taken as a whole, these model results strongly suggest that the impact of ozone depletion on SESA precipitation has been as large as, and quite possibly larger than, the one caused by increasing greenhouse gases over the same period.  相似文献   

Integrating the LISFLOOD‐FP 2D hydrodynamic model with the CAESAR model: implications for modelling landscape evolution     

Tom J. Coulthard  Jeff C. Neal  Paul D. Bates  Jorge Ramirez  Gustavo A. M. de Almeida  Greg R. Hancock 《地球表面变化过程与地形》2013,38(15):1897-1906

Landscape evolution models (LEMs) simulate the geomorphic development of river basins over long time periods and large space scales (100s–1000s of years, 100s of km²). Due to these scales they have been developed with simple steady flow models that enable long time steps (e.g. years) to be modelled, but not shorter term hydrodynamic effects (e.g. the passage of a flood wave). Nonsteady flow models that incorporate these hydrodynamic effects typically require far shorter time steps (seconds or less) and use more expensive numerical solutions hindering their inclusion in LEMs. The recently developed LISFLOOD‐FP simplified 2D flow model addresses this issue by solving a reduced form of the shallow water equations using a very simple numerical scheme, thus generating a significant increase in computational efficiency over previous hydrodynamic methods. This leads to potential convergence of computational cost between LEMs and hydrodynamic models, and presents an opportunity to combine such schemes. This paper outlines how two such models (the LEM CAESAR and the hydrodynamic model LISFLOOD‐FP) were merged to create the new CAESAR‐Lisflood model, and through a series of preliminary tests shows that using a hydrodynamic model to route flow in an LEM affords many advantages. The new model is fast, computationally efficient and has a stronger physical basis than a previous version of the CAESAR model. For the first time it allows hydrodynamic effects (tidal flows, lake filling, alluvial fans blocking valley floor) to be represented in an LEM, as well as producing noticeably different results to steady flow models. This suggests that the simplification of using steady flow in existing LEMs may bias their findings significantly. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

Spatio-Temporal Analysis of the Concentration and Composition of Planktonic Cyanobacteria Community in a Tropical Reservoir Chain     

Luisa María  Múnera P.  Pino  Nancy J.  Peñuela  Gustavo A. 《Water Resources》2021,48(6):1001-1012

Water Resources - Cyanobacteria are very heterogeneous microorganisms that are important in both natural and artificial environments. Nevertheless, an uncontrolled growth of cyanobacteria, or...  相似文献   

Agrometeorological models for forecasting the qualitative attributes of “Valência” oranges     

Victor?Brunini?MoretoEmail author  Glauco?de Souza?Rolim  Bruno?Gustavo?Zacarin  Ana?Paula?Vanin  Leone?Maia?de?Souza  Rodrigo?Rocha?Latado 《Theoretical and Applied Climatology》2017,130(3-4):847-864

Forecasting is the act of predicting unknown future events using available data. Estimating, in contrast, uses data to simulate an actual condition. Brazil is the world’s largest producer of oranges, and the state of São Paulo is the largest producer in Brazil. The “Valência” orange is among the most common cultivars in the state. We analyzed the influence of monthly meteorological variables during the growth cycle of Valência oranges grafted onto “Rangpur” lime rootstocks (VACR) for São Paulo, and developed monthly agrometeorological models for forecasting the qualitative attributes of VACR in mature orchard. For fruits per box for all months, the best accuracy was of 0.84 % and the minimum forecast range of 4 months. For the relation between °brix and juice acidity (RATIO) the best accuracy was of 0.69 % and the minimum forecast range of 5 months. Minimum, mean and maximum air temperatures, and relative evapotranspiration were the most important variables in the models.  相似文献   

Growth and energy budget in juvenile croaker (Micropogonias furnieri (Desmarest 1823))     

Abud  Eddie O. Aristizabal; Prenski  Leszek B.; Daleo  Gustavo R. 《ICES Journal of Marine Science》1992,49(1):65-68

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Erratum to: Climate change projections over three metropolitan regions in Southeast Brazil using the non-hydrostatic Eta regional climate model at 5-km resolution     

Lyra  Andre  Tavares  Priscila  Chou  Sin Chan  Sueiro  Gustavo  Dereczynski  Claudine  Sondermann  Marcely  Silva  Adan  Marengo  José  Giarolla  Angélica 《Theoretical and Applied Climatology》2018,132(1-2):683-683

Theoretical and Applied Climatology -  相似文献