Soil controls water distribution, which is crucial for accurate hydrological modeling. MOHID-Land is a physically based, spatially distributed model that uses van Genuchten–Mualem (VGM) functions to calculate water content in porous media. The hydraulic soil parameters of VGM are dependent on soil type and are typically estimated from experimental data; however, they are often obtained using pedotransfer functions, which carry significant uncertainty. As a result, calibration is frequently required to account for both the natural spatial variability of soil and uncertainties estimation. This study focuses on a representative Atlantic Forest watershed. It assesses the sensitivity of channel flow to VGM parameters using a mathematical approach based on residuals derivative, aimed at enhancing soil calibration efficiency for MOHID-Land. The model’s performance significantly improved following calibration, considering only five parameters. The NSE improved from 0.16 on the base simulation to 0.53 after calibration. A sensitivity analysis indicated the curve adjustment parameter ($n$) as the most sensitive parameter, followed by saturated water content (${\theta }_s$) considering the 10% variation. Additionally, a combined change in ${\theta }_s$, $n$, residual water content (${\theta }_r$), curve adjustment parameter ($\alpha$), and saturated conductivity ($K_{sat}$) values by 10% significantly improves the model’s performance, by reducing channel flow peaks and increasing baseflow.

De acordo com a ONU é crescente a tendência de urbanização sendo projetado um crescimento mundial em termos absolutos atingindo 665 em 2050. Utilizando imagens digitais orbitais e técnicas de sensoriamento remoto, este trabalho teve por objetivo avaliar o comportamento do balanço de energia da cidade de Campos dos Goytacazes, RJ contextualizando o estresse hídrico e correlacionando-o com a temperatura da superfície. Observou-se que o solo urbanizado em comparação com a área não construída apresentou os maiores fluxos de calor sensível e de calor no solo. Nas áreas urbanas foram encontrados os menores valores de saldo de radiação e fluxo de calor latente, gerando temperaturas mais elevadas no solo urbano e as áreas vegetadas apresentaram um maior fluxo de calor latente e menor fluxo de calor do solo. Observou-se ainda uma correlação de 96% entre o estresse hídrico e a temperatura, influenciando fortemente os fluxos da energia.Palavras-chaves: sensoriamento remoto, landsat 8, ilhas de calor, SEBAL Energy balance in the urban perimeter of Campos dos Goytacazes, RJ: A case study ABSTRACTAccording to the UN, the urbanization trend is growing, with a global growth projected in absolute terms reaching 665 in 2050. Using orbital digital images and remote sensing techniques, this work aimed to evaluate the behavior of the energy balance of the city of Campos dos Goytacazes, RJ contextualizing water stress and correlating it with surface temperature. It was observed that the urbanized land compared to the non-built-up area presented the highest fluxes of sensible heat and heat in the soil. In urban areas, the lowest values of radiation balance and latent heat flux were found, generating higher temperatures in the urban soil, and vegetated areas presented a greater latent heat flux and lower soil heat flux. There was also a correlation of 96% between water stress and temperature, strongly influencing energy flows, or for changes in the energy balance of the environment, further analyzes are proposed in different water conditions to compare with the results obtained with this work.Keywords: remote sensing, landsat 8, heat islands, SEBAL, temperature

This paper is aimed at performing a group of experiments to evaluate the sensitivity to cumulus and microphysics schemes, as represented in numerical simulations of the Weather Research and Forecasting (WRF) model. The convective schemes of Kain-Fritsch (KF), Betts-Miller-Janjic (BMJ), Grell-Devenyi (GD), Grell-Freita (GF), Grell 3D (G3D), Tiedtke and New Tiedtke (NT) were tested in association with the microphysics schemes of Kessler, Purdue Lin, WSM3, WSM5, WSM6, ETA (Ferrier) and Goddard (totaling forty-nine experiments) in order to identify the combination which best represents the cumulative rainfall distribution in the Paraíba do Sul watershed. In order to evaluate the best performance experiments, they were submitted to statistical tests of bias (BIAS), root mean square error (RMSE), absolute mean error (MAE) and Coefficient of Determination (R2). Results show that combinations WSM5 and GD; Goddard and G3D; Perdue Lin and G3D; WSM5 and G3D form a group of four physical configurations statistically similar and able to predict well the mean rainfall in the Paraiba do Sul watershed. It was noticed also that the cumulus scheme has a greater weight than microphysics in rainfall simulations being GD3 the best performing.

Hydrological modeling is essential for the sustainable management of watershed systems. Physically based models like MOHID-Land simulate soil water dynamics using Richards’ equation, parameterized through the van Genuchten–Mualem (VGM) model. Although the sensitivity of individual VGM parameters—residual water content (${\theta }_r$), saturated water content (${\theta }_s$), pore size distribution ($n$), inverse of air entry pressure ($\alpha$), and saturated hydraulic conductivity ($K_{sat}$)—is well documented, their combined effects remain underexplored. This study assessed both isolated and joint impacts of these parameters through a deterministic ±10% perturbation scheme, resulting in 31 unique parameter combinations. Model performance was evaluated using the Nash–Sutcliffe Efficiency (NSE) and Percent Bias (PBIAS). Full-parameter interaction achieved the best results (NSE = 0.50, PBIAS = 25.32), compared to the uncalibrated baseline (NSE = 0.01, PBIAS = 34.06). The pair ${\theta }_s$ and $n$ emerged as the most influential. Adding secondary parameters to this core pair yielded only marginal performance gains, while removing them from the full set caused similarly marginal declines. These findings reveal a hierarchical sensitivity structure, emphasizing ${\theta }_s$ and $n$ as key targets for calibration. Prioritizing this pair enables a more efficient soil calibration process, preserving model accuracy while reducing computational cost by limiting parameter space exploration.

O café Conilon representa boa parcela da cafeicultura brasileira e é fundamental o entendimento de como a cultura se relaciona com a energia disponível no ambiente. Devido a isso, buscou-se com este trabalho determinar os componentes do balanço energético da cultura do cafeeiro Conilon na região Norte Fluminense durante sete safras. O experimento foi conduzido em um campo de cultivo na área pertencente à Universidade Estadual do Norte Fluminense Darcy Ribeiro, em Campos dos Goytacazes, RJ, que contém uma estação micrometeorológica que monitorou os dados ambientais entre junho de 2015 a maio de 2022. De posse dessas informações, realizou-se o balanço de energia pelo método da razão de Bowen, que possibilitou determinar a evapotranspiração da cultura (ETc), a evapotranspiração de referência (ET0) e o coeficiente da cultura (Kc). O método de balanço de energia pela razão de Bowen teve desempenho satisfatório e indicou que 66% de Rn foi convertido em LE, 24% em H e 10% em G. A evapotranspiração média da cultura foi de 3,81 mm.dia-1 e o Kc médio por safra teve tendência de aumento ao longo do experimento e variou de 0,82 a 0,92. O café Conilon apresentou produtividade média de 3,43 t.ha-1 (57,16 sc.ha-1) e concluiu-se em média foi produzido 0,08 g por MJ de energia líquida.