INTER-SEASONAL AND INTER-BASINS HYDROLOGICAL COUPLING IN SOUTH AMERICA

2021 ◽  
Author(s):  
Paulo Rodrigo Zanin ◽  
Prakki Satyamurty
Keyword(s):  
Soil Moisture ◽  
Amazon Basin ◽  
Winter Season ◽  
Western Region ◽  
South American ◽  
La Plata ◽  
La Plata Basin ◽  
Precipitation Recycling ◽  
Source Sink ◽  
Southeastern Region

AbstractThe inter-seasonal and inter-basins hydrological couplings between the Amazon and the La Plata basins are obtained with the help of ERA-5 atmospheric reanalysis, MERGE/CPTEC precipitation, GLEAM evapotranspiration and the GLDAS/Noah soil moisture datasets. The hypotheses formulated by Zanin and Satyamurty (2020a) about the hydrological processes interconnecting the Amazon Basin and the La Plata Basin are tested. A new method for finding the source-sink relationships among the boxes (regions) is presented. The precipitation recycling, frequency of source-sink behaviors, the soil moisture memory and the continental moisture transport between remote regions are evaluated. The main result of this study is that the amount of water precipitated over the Southeastern region of the Amazon Basin at the end of the South American Monsoon during autumn season, influences the amount of precipitation during winter season over the Central-western region of the La Plata Basin.

scholarly journals On the importance of cascading moisture recycling in South America

2014 ◽  
Vol 14 (23) ◽  
pp. 13337-13359 ◽  
Author(s):  
D. C. Zemp ◽  
C.-F. Schleussner ◽  
H. M. J. Barbosa ◽  
R. J. van der Ent ◽  
J. F. Donges ◽  
...  
Keyword(s):  
Land Use ◽  
South America ◽  
Complex Network ◽  
Amazon Basin ◽  
South American ◽  
Total Precipitation ◽  
Wet Season ◽  
La Plata ◽  
Moisture Recycling ◽  
La Plata Basin

Abstract. Continental moisture recycling is a crucial process of the South American climate system. In particular, evapotranspiration from the Amazon basin contributes substantially to precipitation regionally as well as over other remote regions such as the La Plata basin. Here we present an in-depth analysis of South American moisture recycling mechanisms. In particular, we quantify the importance of cascading moisture recycling (CMR), which describes moisture transport between two locations on the continent that involves re-evaporation cycles along the way. Using an Eulerian atmospheric moisture tracking model forced by a combination of several historical climate data sets, we were able to construct a complex network of moisture recycling for South America. Our results show that CMR contributes about 9–10% to the total precipitation over South America and 17–18% over the La Plata basin. CMR increases the fraction of total precipitation over the La Plata basin that originates from the Amazon basin from 18–23 to 24–29% during the wet season. We also show that the south-western part of the Amazon basin is not only a direct source of rainfall over the La Plata basin, but also a key intermediary region that distributes moisture originating from the entire Amazon basin towards the La Plata basin during the wet season. Our results suggest that land use change in this region might have a stronger impact on downwind rainfall than previously thought. Using complex network analysis techniques, we find the eastern side of the sub-tropical Andes to be a key region where CMR pathways are channeled. This study offers a better understanding of the interactions between the vegetation and the atmosphere on the water cycle, which is needed in a context of land use and climate change in South America.

scholarly journals On the importance of cascading moisture recycling in South America

2014 ◽  
Vol 14 (11) ◽  
pp. 17479-17526 ◽  
Author(s):  
D. C. Zemp ◽  
C.-F. Schleussner ◽  
H. M. J. Barbosa ◽  
R. J. Van der Ent ◽  
J. F. Donges ◽  
...  
Keyword(s):  
South America ◽  
River Basin ◽  
Amazon Basin ◽  
South American ◽  
The South ◽  
Wet Season ◽  
La Plata ◽  
Moisture Recycling ◽  
La Plata Basin ◽  
Recycling Networks

Abstract. Continental moisture recycling is a crucial process of the South American climate system. Evapotranspiration from the Amazon river basin contributes to precipitation regionally and in the La Plata river basin. Here we present an in-depth analysis of South American moisture recycling. We quantify the importance of "cascading moisture recycling", which describes the exchange of moisture between the vegetation and the atmosphere through precipitation and re-evaporation cycles on its way between two locations on the continent. We use the Water Accounting Model 2-layers (WAM-2layers) forced by precipitation from TRMM and evapotranspiration from MODIS for the period 2001 until 2010 to construct moisture recycling networks. These networks describe the direction and amount of moisture transported from its source (evapotranspiration) to its destination (precipitation) in South America. Model-based calculations of continental and regional recycling ratios in the Amazon basin compare well with other existing studies using different datasets and methodologies. Our results show that cascading moisture recycling contributes about 10% to the total precipitation over South America and 17% over the La Plata basin. Considering cascading moisture recycling increases the total dependency of the La Plata basin on moisture from the Amazon basin by about 25% from 23 to 29% during the wet season. Using tools from complex network analysis, we reveal the importance of the south-western part of the Amazon basin as a key intermediary region for continental moisture transport in South America during the wet season. Our results suggest that land use change in this region might have a stronger impact on downwind rainfed agriculture and ecosystem stability than previously thought.

Exposure to 19 elements via water ingestion and dermal contact in several South American environments (La Plata Basin): From Andes and Atlantic Forest to sea front

2019 ◽  
Vol 149 ◽  
pp. 103986 ◽  
Author(s):  
E. Avigliano ◽  
C. Clavijo ◽  
P. Scarabotti ◽  
S. Sánchez ◽  
S. Llamazares Vegh ◽  
...  
Keyword(s):  
Atlantic Forest ◽  
South American ◽  
Dermal Contact ◽  
La Plata ◽  
Water Ingestion ◽  
La Plata Basin

Deforestation Impacts on Amazon-Andes Hydroclimatic Connectivity

2021 ◽  
Author(s):  
Juan P. Sierra ◽  
C. Junquas ◽  
J. C. Espinoza ◽  
H. Segura ◽  
T. Condom ◽  
...  
Keyword(s):  
Transition Region ◽  
Amazon Basin ◽  
Atmospheric Stability ◽  
Austral Summer ◽  
Hadley Cell ◽  
South American ◽  
Tropical Andes ◽  
Tropical Glaciers ◽  
Precipitation Recycling ◽  
The Rich

Abstract Amazonian deforestation has accelerated during the last decade, threatening an ecosystem where almost one third of the regional rainfall is transpired by the local rainforest. Due to the precipitation recycling, the southwestern Amazon, including the Amazon-Andes transition region, is particularly sensitive to forest loss. This study evaluates the impacts of Amazonian deforestation in the hydro-climatic connectivity between the Amazon and the eastern tropical Andes during the austral summer (December-January-February) in terms of hydrological and energetic balances. Using 10-year high-resolution simulations (2001–2011) with the Weather Research and Forecasting Model, we analyze control and deforestation scenario simulations. Regionally, deforestation leads to a reduction in the surface net radiation, evaporation, moisture convergence and precipitation (~ 20%) over the entire Amazon basin. In addition, during this season, deforestation increases the atmospheric subsidence over the southern Amazon and weakens the regional Hadley cell. Atmospheric stability increases over the western Amazon and the tropical Andes inhibiting convection in these areas. Consequently, major deforestation impacts are observed over the hydro-climate of the Amazon-Andes transition region. At local scale, nighttime precipitation decreases in Bolivian valleys (~ 20–30%) due to a strong reduction in the humidity transport from the Amazon plains toward Andes linked to the South American low-level jet. Over these valleys, a weakening of the daytime upslope winds is caused by local deforestation, which reduces the turbulent fluxes at lowlands. These alterations in rainfall and atmospheric circulation could impact the rich Andean ecosystems and its tropical glaciers.

scholarly journals A Note on Soil Moisture Memory and Interactions with Surface Climate for Different Vegetation Types in the La Plata Basin

2015 ◽  
Vol 16 (2) ◽  
pp. 716-729 ◽  
Author(s):  
Anna A. Sörensson ◽  
Ernesto Hugo Berbery
Keyword(s):  
Soil Moisture ◽  
Surface Temperature ◽  
Statistical Significance ◽  
Surface Fluxes ◽  
Maximum Temperature ◽  
Seasonal Forecasts ◽  
La Plata ◽  
La Plata Basin ◽  
Surface Climate ◽  
Soil Moisture Initialization

Abstract This work examines the evolution of soil moisture initialization biases and their effects on seasonal forecasts depending on the season and vegetation type for a regional model over the La Plata basin in South America. WRF–Noah simulations covering multiple cases during a 2-yr period are designed to emphasize the conceptual nature of the simulations at the expense of the statistical significance of the results. Analysis of the surface climate shows that the seasonal predictive skill is higher when the model is initialized during the wet season and the initial soil moisture differences are small. Large soil moisture biases introduce large surface temperature biases, particularly for savanna, grassland, and cropland vegetation covers at any time of the year, thus introducing uncertainty in the surface climate. Regions with evergreen broadleaf forest have roots that extend to the deep layer whose moisture content affects the surface temperature through changes in the partitioning of the surface fluxes. The uncertainties of monthly maximum temperature can reach several degrees Celsius during the dry season in cases when 1) the soil is much wetter in the reanalysis than in the WRF–Noah equilibrium soil moisture and 2) the memory of the initial value is long because of scarce rainfall and low temperatures. This study suggests that responses of the atmosphere to soil moisture initialization depend on how the initial wet and dry conditions are defined, stressing the need to take into account the characteristics of a particular region and season when defining soil moisture initialization experiments.

scholarly journals Integrative taxonomy reveals disjunct distribution and first record of Hoplias misionera (Characiformes: Erythrinidae) in the Amazon River basin: morphological, DNA barcoding and cytogenetic considerations

2021 ◽  
Vol 19 (2) ◽  
Author(s):  
Karen L. A. Guimarães ◽  
Juan J. Rosso ◽  
Mendelsohn F. B. Souza ◽  
Juan M. Díaz de Astarloa ◽  
Luís R. R. Rodrigues
Keyword(s):  
Dna Barcoding ◽  
Amazon Basin ◽  
First Record ◽  
Morphological Data ◽  
Disjunct Distribution ◽  
Valid Species ◽  
Integrative Approach ◽  
Molecular Evidence ◽  
La Plata ◽  
La Plata Basin

Abstract The Hoplias malabaricus group encompasses six valid species and still is believed to harbors cryptic diversity. In this work, an integrative approach including morphological, DNA barcoding, and cytogenetic considerations was conducted to characterize a population of H. malabaricus from the Amazon basin that was recently allocated in the same mitochondrial lineage with H. misionera, a species originally described from La Plata basin. The DNA barcoding analysis revealed that the Amazon population nested together with H. misionera specimens from the La Plata basin (BIN AAB1732) in the same cluster. The intragroup distance (0.5%) was 12 times lower than the nearest neighbor (6%) distance. The morphometric analysis demonstrated slightly variation between Amazon and La Plata populations, being the former composed by larger specimens. Further morphological data supported the molecular evidence of H. misionera inhabiting Amazon basin. The karyotype characterization of H. misionera in the Amazon population showed 2n=40 and karyotypic formulae 20m+20sm, that added to C-banding, Ag-NOR and 18S results are suggestive of the similarity to karyomorph C of H. malabaricus. This work reveals the first record of H. misionera outside of La Plata basin and expands the species distribution for 2500 km northward until the Marajó Island, estuary of Amazonas River.

scholarly journals Observational evidences on the modulation of the South American Low Level Jet east of the Andes according the ENSO variability

2009 ◽  
Vol 27 (2) ◽  
pp. 645-657 ◽  
Author(s):  
G. A. M. Silva ◽  
T. Ambrizzi ◽  
J. A. Marengo
Keyword(s):  
South America ◽  
South American ◽  
The South ◽  
Trade Winds ◽  
La Plata ◽  
The Andes ◽  
La Plata Basin ◽  
Normal Frequency ◽  
Rainfall Anomalies ◽  
Low Level Jet

Abstract. The differences on the phase and wavelength of the quasi-stationary waves over the South America generated by El Niño (EN) and La Niña (LN) events seem to affect the daily evolution of the South American Low Level Jet east of the Andes (SALLJ). For the austral summer period of 1977–2004 the SALLJ episodes detected according to Bonner criterion 1 show normal to above-normal frequency in EN years, and in LN years the episodes show normal to below-normal frequency. During EN and LN years the SALLJ episodes were associated with positive rainfall anomalies over the La Plata Basin, but more intense during LN years. During EN years the increase in the SALLJ cases were associated to intensification of the Subtropical Jet (SJ) around 30° S and positive Sea Level Pressure (SLP) anomalies over the western equatorial Atlantic and tropical South America, particularly over central Brazil. This favored the intensification of the northeasterly trade winds over the northern continent and it channeled by the Andes mountain to the La Plata Basin region where negative SLP are found. The SALLJ cases identified during the LN events were weaker and less frequent when compared to those for EN years. In this case the SJ was weaker than in EN years and the negative SLP anomalies over the tropical continent contributed to the inversion of the northeasterly trade winds. Also a southerly flow anomaly was generated by the geostrophic balance due to the anomalous blocking over southeast Pacific and the intense cyclonic transient over the southern tip of South America. As result the warm tropical air brought by the SALLJ encounters the cold extratropical air from the southerly winds over the La Plata basin. This configuration can increase the conditional instability over the La Plata basin and may explain the more intense positive rainfall anomalies in SALLJ cases during LN years than in EN years.

scholarly journals Biomass burning CCN enhance the dynamics of a mesoscale convective system over the La Plata Basin: a numerical approach

2018 ◽  
Vol 18 (3) ◽  
pp. 2081-2096
Author(s):  
Gláuber Camponogara ◽  
Maria Assunção Faus da Silva Dias ◽  
Gustavo G. Carrió
Keyword(s):  
Biomass Burning ◽  
Amazon Basin ◽  
Cloud Condensation Nuclei ◽  
Mesoscale Convective System ◽  
Mesoscale Convective Systems ◽  
Convective System ◽  
La Plata ◽  
Convective Systems ◽  
La Plata Basin ◽  
Mesoscale Convective

Abstract. High aerosol loadings are discharged into the atmosphere every year by biomass burning in the Amazon and central Brazil during the dry season (July–December). These particles, suspended in the atmosphere, can be carried via a low-level jet toward the La Plata Basin, one of the largest hydrographic basins in the world. Once they reach this region, the aerosols can affect mesoscale convective systems (MCSs), whose frequency is higher during the spring and summer over the basin. The present study is one of the first that seeks to understand the microphysical effects of biomass burning aerosols from the Amazon Basin on mesoscale convective systems over the La Plata Basin. We performed numerical simulations initialized with idealized cloud condensation nuclei (CCN) profiles for an MCS case observed over the La Plata Basin on 21 September 2010. The experiments reveal an important link between CCN number concentration and MCS dynamics, where stronger downdrafts were observed under higher amounts of aerosols, generating more updraft cells in response. Moreover, the simulations show higher amounts of precipitation as the CCN concentration increases. Despite the model's uncertainties and limitations, these results represent an important step toward the understanding of possible impacts on the Amazon biomass burning aerosols over neighboring regions such as the La Plata Basin.

scholarly journals Intense Rainfall Events Affecting the La Plata Basin

2006 ◽  
Vol 7 (4) ◽  
pp. 769-787 ◽  
Author(s):  
Viviane B. S. Silva ◽  
Ernesto H. Berbery
Keyword(s):  
Large Scale ◽  
Amazon Basin ◽  
Level Structure ◽  
Intense Rainfall ◽  
Rainfall Events ◽  
La Plata ◽  
La Plata Basin ◽  
Intense Precipitation ◽  
Eta Model ◽  
Precipitation Events

Abstract The circulation features associated with intense precipitation events over the La Plata Basin (LPB) during the austral summers of 2001/02 and 2002/03 are investigated using the Eta Model runs generated at the University of Maryland. Based on the main mode of variability over LPB, two regions were selected: (i) the region of Brazil that is at the core of the South American summer monsoon system (SAMS) and (ii) the central region of LPB in southeastern South America (SESA). First, a comparison between the 24-h total precipitation in the Eta Model and the 24-h observed precipitation was made. Results show that the Eta Model captures well the temporal variability of precipitation events in both regions, although a positive bias is noticed over SAMS. Likewise, the model reproduces the distribution of precipitation rate over SESA, but not over SAMS. Nevertheless, the distribution of the moisture flux convergence intensity, which represents the dynamical forcing, is closer in shape to the observed precipitation distribution, suggesting that the model can be a useful tool in identifying the forcing for heavy precipitation events over both regions. Composites of atmospheric and surface variables were constructed for intense precipitation events during austral summer over both regions. Intense rainfall over the central La Plata Basin (SESA) is linked to an amplified upper-tropospheric midlatitude wave pattern in which rainfall occurs just east of an enhanced cyclonic circulation. Accompanying this circulation pattern, an enhanced low-level jet (LLJ) transports warm, moist air from the Amazon toward the region, contributing to an increase in the thermal contrast over SESA. The combined patterns of thermal and dynamical variables suggest that large-scale systems, like frontal systems, are important in producing intense rainfall events. The SAMS region events have a similar upper-level structure as in SESA, but they are longer lived. In this case, the moisture fluxes are determined by an eastward shift of the LLJ, but also directly from the Amazon Basin to the north. As expected, precipitation events produce large increases of simulated runoff. The largest impact is on the SESA region, affecting the streamflow of the Paraná, Paraguay, and Uruguay, the three main rivers of the LPB.

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