Luciana Barros Pinto

Análise de sensibilidade dos coeficientes genéticos do modelo Canegro/DSSAT.

A analise de sensibilidade dos coeficientes geneticos utilizados na simulacao de produtividade da cana de acucar pelo modelo Canegro/DSSAT (CD) foi realizada com o objetivo de identificar quais parâmetros tem maior relevância na calibracao do modelo. O CD faz uso de 20 parâmetros que tem como objetivo capturar as diferencas entre as cultivares de cana-de-acucar. A analise de sensibilidade foi desenvolvida variando um parâmetro por vez dentro de um determinado intervalo e mantendo os demais constantes. Foram simulados o peso seco do colmo, indice de area foliar de folhas verdes e peso seco de sacarose ao final de cada ciclo de cultivo em um periodo de vinte anos, entre 1995 e 2014, considerando tres datas de plantio, 01 de agosto, 01 de setembro e 01 de outubro. As simulacoes foram feitas para o municipio de Pelotas – RS e os resultados foram avaliados pelo desvio padrao (D). Os resultados mostram que os coeficientes geneticos de maior sensibilidade na simulacao do peso seco do colmo foram PARCEmax (D ≈ 6 t.ha-1) e STKPFmax (D ≈ 5 t.ha-1). Para a simulacao de peso seco de sacarose os coeficientes geneticos de maior sensibilidade tambem foram PARCEmax (D ≈ 3,5 t.ha-1) e STKPFmax (D ≈ 3 t.ha-1). Para a simulacao do indice de area foliar maximo os coeficientes geneticos mais sensiveis foram LFMAX (D ≈ 2 cm2.cm-2), TT_POPGROWTH (D ≈ 1,4 cm2.cm-2) e Mxlfarea (D ≈ 1 cm2.cm-2). Os resultados tambem mostram que as diferencas na data de plantio tem influencia na sensibilidade dos coeficientes geneticos.

Parametrization of Models and Use of Estimated Global Solar Radiation Data in the Irrigated Rice Yield Simulation

The objective of this study was to evaluate the use of estimated global solar radiation data in the simulations of potential yield of irrigated rice. Global solar radiation was estimated by four empirical models, based on air temperature, and a meteorological satellite derivated. The empirical models were calibrated and validated for 10 sites, representative of the six rice regions of the State of Rio Grande do Sul Brazil. To evaluate the impact of the radiation estimates on irrigated rice yield simulations, the CERES-Rice model, calibrated for four cultivars, was used. The estimates of global solar radiation of the empirical models based on the air temperature showed deviations, from the observed values, of 20 to 30% and the estimated by satellite deviations of more than 30%. The global solar radiation data estimated by the Hargreaves and Samani, Donatelli and Campbell and derived satellite (PowerNasa) type air temperature-based empirical models can be used as input data in simulation models of crop growth, development and productivity of irrigated rice.

ENVIRONMENTAL CHARACTERISTICS RELATED TO HAIL OCCURRENCE IN SOBRADINHO-RS IN DECEMBER 2008

This work analyzed thermodynamic and synoptic environmental characteristics associated with the occurrence of hail generated by a Mesoscale Convective System (MCS) that reached Sobradinho in Rio Grande do Sul (RS) from December 09 to 10, 2008 as well as morphological and radiative behavior of this MCS. These analyses allowed highlight the main atmospheric conditions which contributed for the occurrence of this event. The results showed that the atmospheric conditions observed in the region (heat and moisture transport at low levels and intense updrafts) were extremely favorable to formation and development of the MCS that began in December 09, 2008, which favored the hail occurrence on the same day in Sobradinho and precipitation in RS in December 09 to 10, 2008.

Evento Extremo de Precipitação Observado no Norte do Rio Grande do Sul

This paper analyzes atmospheric conditions related to an extreme rainfall event that reached Northern of Rio Grande do Sul (RS) in July 10, 2007. Different data sources were used: rainfall daily data from 16 meteorological surface stations of RS to verify the rainfall registered on RS during the event; infra-red (channel 4) satellite imagery from GOES 10 (Geostationary Operational Environmental Satellite), to analyze the evolution of meteorological system that generated the event; surface and altitude synoptic charts from July 10, 2007 at 00 UTC to analyze the meteorological systems acting on the RS and data from NCEP-CFSR Reanalysis (National Centers for Environmental Prediction -- Climate Forecast System Reanalysis), to analyze the large-scale environment associated with the event. The results showed that the circulation in low-level of the atmosphere contributed to supply the study area with large amount of heat and humidity. This condition combined with the occurrence of Frontal System observed from July 09, 2007 contributed to the organization of atmospheric instability and convective cloudiness observed, favoring the occurrence of the extreme rainfall registered in Northern RS in July 10, 2007.

THE WATER REGIME OF RS DURING THE EL NIÑO-SOUTHERN OSCILLATION (ENSO )EVENTS OF THE YEARS 1987 AND 1999

In this work were determined and analyzed the seasonal water balance (WB) anomalies for 1987 and 1999 in relation to the Rio Grande do Sul (RS) climatic WB in the period from 1977 to 2006 to evaluate the El Nino (EN) 1987 and La Nina (LN) 1999 impact in the RS water regime, detecting periods and regions with excess or deficit of water. To calculate the WB were used air temperature and rainfall data, obtained from the National Institute of Meteorology. The water balances were calculated by Thornthwaite and Mather method, and evapotranspiration by the Thornthwaite method. The results showed that El Nino-Southern Oscillation (ENSO) affected the water regime of the analyzed years. The 1987 year was wetter than normal in most the RS, except in the extreme south the state where it was found negative precipitation anomalies and deficit of water, due to the occurrence of EN. On the other hand, 1999 was a year drier than the climatology from 1977 to 2006, due to the occurrence of LN. Excess of water observed in 1999 were registered on RS north and northwest regions.

Zoneamento agro-climático da cana-de-açúcar para o estado de Minas Gerais com base em regressões múltiplas

AGRO-CLIMATOLOGICAL ZONING OF CANE SUGAR FOR THE MINAS GERAIS STATE BASED ON MULTIPLE REGRESSIONS It was aimed in this work, through the geospatialization and multiple regression analysis, the identification of the suitable, restricted and unsuitable regions for cultivation of sugar cane in Minas Gerais State. It was used temperature and water deficit data from 32 meteorological stations located in the State. The data of water deficit were determined using the water balance according to Thornthwaite and Mather (1955) method. Most of the state is restricted to the cultivation, according to the productivity criteria related with thermal and hydric demands of the culture.

Ambiente sinótico e perfis verticais de um Sistema Convectivo de Mesoescala (SCM)

The BRAMS regional model was used to simulate the large scale environment and the vertical profile of some meteorological variables, to the most precipitant CMS that reaches RS, from November 2002 to February 2003. The CMS selected was observed from 02/19/2003 to 02/20/2003. The model simulation, with one hour issues, allowed to detail the synoptic environment where the CMS was during its life cycle, being able to reproduce the suitable conditions to its beginning, development and dissipation. It was possible too, describe the behavior of the vertical profiles of the wind, specific humidity, vertical velocity and equivalent potential temperature, to each phase of the CMS life cycle.