Climatological Water Balance Research Articles

Hydrological Changes in a Fruit Growing Area Under the Influence of Climate Change: on the Amazon Coast

Objective: The objective of this study is to investigate the water consumption of the mango orchard using the method proposed by Thornthwaite and Mather (1955), called Climatological Water Balance, with the aim of assisting in agricultural planning and decision making. Theoretical Framework: The Climatological Water Balance was initially developed with the aim of characterizing the climate of a region, in order to be used in the climate classification developed by Thornthwaite in the 1940s. Later, this method began to be used for agronomic purposes given the great interrelationship of agriculture with climatic conditions. Method: The methodology adopted for this research comprises the information used in the preparation of the water balance and was acquired by instrumentation implemented at the experimental hose site in the village of Cuiarana, district of Salinópolis in the northeast of the state of Pará. The meteorological data were obtained in the Project tower LBA where are measured, by automatic instrumentation, such as: average air temperature (Tar) the relative air humidity (RH) through the HMP45 probe, the Rain acquired by the CSI MODEL TB4-L RAIN GAGE ​​from Campbell Scientific, the collection of data was carried out using a datalogger with recording every 10s and storage of the average every 10 min. Results and Discussion: The results obtained revealed an increase in air temperature mainly in El-niño years and with a strong reduction in rainfall in these years of approximately 30 to 40% in the annual accumulation. These results imply a reduction in productivity and the regional and local impact of the hydrological cycle. Research Implications: The practical and theoretical implications of this research are discussed, providing insights into how the results can be applied or influence practices in the field of fruit growing. These implications may include the importance of the vegetation cover of the mango orchard on the socio-environmental quality of the village of Cuiarana. Originality/Value: This study contributes to the literature on mango crops that are not irrigated, it also makes it possible to optimize sowing times, taking into account the average water availability in the studied region, resulting in a more efficient use of rainfall for agricultural production. The relevance and value of this research are evidenced by the fact that the study in the northeast of Pará is still precarious in terms of water consumption by the plant in a region with water deficiency.

The climate and climatological water balance of Brazilian semi-arid mountainous areas and inland depression

The climate and climatological water balance of Brazilian semi-arid mountainous areas and inland depression

Water Balance, Climate Classification and Empirical Distribution of the Probability of Rain for the Region of Tangará da Serra – MT

Objective: The present work aimed to describe the Climatological Water Balance (BHC), carry out the Climate Classification (CC) and evaluate the Empirical Probability (EP) of rainfall occurrence for the region of Tangará da Serra – MT. Theoretical Frame: This study used the following main citations as a theoretical basis: National Water Agency (ANA) and National Institute of Meteorology (INMET), source of climate data; Thornthwaite & Mather (1955) for the climatological water balance methodology; Thornthwaite (1948) and Koppen (1900) for climate classification; and Thom (1966) for the methodology of probability of occurrence and return period of rain. Method: To carry out the study, a series of 31 years of climate data was used, covering the period from 1989 to 2019, obtained from the National Water Agency (ANA) and the National Institute of Meteorology (INMET). Filling gaps in the data was carried out using the Regional Weighting method, according to the methodology of Mello et al. (2017). The climatological water balance was estimated according to Thornthwaite & Mather (1955). The climate classification was obtained using the methodologies of Thornthwaite (1948) and Koppen (1900). The probability of occurrence and the period of return of rain were achieved using the methods of Thom (1966). Results and Conclusions: Through studies carried out, it was found that the average annual precipitation in Tangará is 1603 mm and the average annual air temperature is 24.5 °C. The months of May, June, July, August and September present a water deficit, while in the months of December, January, February, March and April there is a water surplus. According to Thornthwaite's methodology, the region has a humid climate, with moderate water deficiency in winter, megathermal and with potential evapotranspiration in the summer less than 48% of the annual potential evapotranspiration, whereas according to Koppen's methodology, the location was classified as megathermal or tropical with drought in the winter. The probability of rainfall less than the maximum average of 47.7 mm is 93.3% and its return time is approximately 15 years. Implications of the research: This research is classified as of great importance for the purposes of the Department of Agricultural Engineering of the State University of Mato Grosso, Campus of Nova Mutum and Tangará da Serra - MT, as well as for the entire academic and scientific community and interested rural producers. in climatic data, water balance and climate of the studied region. Originality and value: This study aimed to show the academic and scientific community and rural producers the behavior of climatic variables throughout the year in the municipality of Tangará da Serra – MT, where this information can be used for agricultural planning in the region and also serve as a basis for future studies.

Climate risk zoning for wheat crops in the southeastern region of Brazil.

Wheat (Triticum aestivum L.) is the second most consumed food in the world. One way to meet this demand is the expansion of wheat cultivation to the Brazilian Cerrado in the southeastern region. However, one of the major limitations is that there are few studies related to wheat climate risk zoning. Thus, this study aimed to determine the agroclimatic zoning of wheat by estimating the water needs satisfaction index (ISNA) in the southeastern region of Brazil. For this purpose, a 60-year historical series of meteorological data was used to calculate the potential evapotranspiration, crop evapotranspiration, and climatological water balance values. To define the agroclimatic zones of wheat and sowing date, the ISNA method was used. The data were analyzed using descriptive statistics to determine the variations. To obtain the agroclimatic zoning of wheat, the geostatistical method of kriging interpolation was used. The regions with the highest rainfall are the south of Minas Gerais and the coast of São Paulo. The sowing period directly impacts the development of the crop, the available water capacity and the ISNA values indicated the spring and summer had better cultivation conditions, and the best window for wheat cultivation is concentrated in the fall due to the limitation of biotic factors. In terms of altitude (>700 m), Minas Gerais has 39.4% of the area suitable for wheat cultivation. Thus, climatic variations within and between the states of the southeastern region should be considered for the positioning of wheat cultivars in these regions to obtain the maximum yield. © 2023 Society of Chemical Industry.

Climate indices and their variabilities in the state of Pernambuco – Brazil

The climatic indices represent part of the characterization of a given region, being obtained through the water balance and the potential evapotranspiration. The objective is to study the fluctuations and perform the analysis and mapping of the indices of humidity, water and aridity, precipitation and average annual air temperature for the State of Pernambuco using the Climatological Water Balance technique according to the [35]. The data used were average monthly precipitation and monthly averages of air temperatures from 1962 to 2015, these data were estimated using the software, Estima_T, while the precipitation data were acquired from the Agencia Pernambucana de Água e Clima. Temperature reductions occurred in accordance with the displacement of the rainy season and the actions and/or contributions of regional and local effects. Elevation and latitude are the physiographic variables that best explain the monthly and annual temperature variation in the study area.

Cultural skills for the municipality of Recife - Pernambuco, Brazil

The objective is to characterize the climate and to carry out zoning and agroclimatic aptitude for pineapple, herbaceous cotton, banana, sugarcane, beans, corn, cassava, castor bean, sisal and sorghum crops, pointing out their possible cultivation skills in the city Recife - PE. A historical series of rainfall and mean air temperature was used to calculate climatological water balance, climatic classification, evapopluviogram construction and agroclimatic zoning of the crops. Recife - PE has full aptitude for the cultivations of pineapple, herbaceous cotton, beans, castor bean, cassava and sisal. For the cultivation of cashew, maize, sugarcane and sorghum we contacted moderate aptitude. Only banana cultivation is restricted due to the region having a marked water deficit. The elements temperature, rainfall were determinant for the calculation of the water balance and the definition of the pluviometric scenarios. The study provides support to decision makers by providing information on Climatological Water Balance, climatic classification, agroclimatic zoning and crop aptitude, favoring adequate planning of agricultural activities and consequently reduction of crop risks.

CLIMATOLOGICAL WATER BALANCE AND CHARACTERIZATION OF WATER RESOURCES IN THE MUNICIPALITY OF PENTECOSTE, CEARÁ

The present work aimed to analyze the climatological water balance and the characteristics of surface water resources in the municipality of Pentecoste, Ceará. The research was divided into three stages: organization and inventory, field studies, and desk research. For the water balance the historical series of 30 years, 1991 to 2020, was investigated and applied to the Normal Water Balance program with the data referring to the coordinates of the rainfall station and average monthly data of precipitation and temperature. It was obtained as a result the description and detailing of the main water courses present in the municipality. In analyzing the volume of reservoirs for the historical series 2004-2021 it is identified that the water supply decreased with the dry period that began in 2011, being the most critical situation during the year 2017, in which the Sítios Novos weir recorded a volume of 0.12%, followed by the Pentecoste and Caxitoré weir with 0.14% and 3.61%, respectively. In regards to the water balance, it is highlighted that the largest precipitation is concentrated in February, March, and April, with respectively 122.35mm, 188.57mm, and 181.46mm. The potential evapotranspiration reaches its apex in December with 180.05mm, the highest temperature of the series, 28.3°C, occurred in November and December and the lowest was 26.7°C in April. The actual evapotranspiration reached the highest level in March with 145mm. It is also noteworthy that 10 months of the year are of water deficiency, except March and April, marked as a replacement, because they are the rainiest months.

Avaliação das Mudanças Climáticas Usando o índice de Humidade da Classificação Climática Thornthwaite no Bioma Pantanal

Abstract Thornthwaite climate classification indices are essential to interpret climate types in the state of the pantanal biome (Mato Grosso do Sul), simplifying calculation process and interpretation of climatological water balance by farmers. However, there are few studies found in the literature that characterize the climate of pantanel biome in different climatic scenarios. We seek to assess climate change using humidity index of Thornthwaite climate classification in pantanal biome. We used historical series of climate data from all 79 municipalities of Mato Grosso do Sul between 1987 and 2017, which were divided into microregions. Air temperature and precipitation were collected on a daily scale. Precipitation and potential evapotranspiration data allowed calculating water balance by the Thornthwaite and Mather method. We characterized all locations as wet and dry using aridity indices proposed by Thornthwaite. The global climate model used was BCC-CSM 1.1 developed at the Beijing Climate Center (BCC) with a resolution of 125 x 125 km. We used the scenarios RCP-2.6, RCP-4, RCP-6 and RCP-8.5 for analyzing 21st century projections (2041-2060 and 2061-2080 periods). Maps were generated from climate indices of Mato Grosso do Sul using kriging interpolation method with spherical model, one neighbor, and 0.25° resolution. The microregions showed different patterns regarding water balance components and humidity index. Humidity index had a mean of 15.94. The prevailing climate in the state of Mato Grosso do Sul is C2 (moist subhumid). The state of Mato Grosso do Sul has two well-defined periods during the year: a dry and a rainy period. Three climate types predominate in Mato Grosso do Sul and, according to the Thornthwaite classification, are B1 (humid), C2 (moist subhumid), and C1 (dry subhumid). Water characterization in Mato Grosso do Sul showed 234.78 mm year−1 of water surplus, 80.8 mm year−1 of water deficit, and 1,114.8 mm year−1 of potential evapotranspiration. Water deficit and potential evapotranspiration decrease as latitude increases. The climatic projections show, in all scenarios, reduce the area classified as umida in the state (B1, B2 and B3), besides adding the dry subhumid class (C1). The Scenario RCP 8.5 in 2061 - 2080 is the most worrisome situation of all, because the state can undergo major changes, especially in the pantanal biome region.

Distribuição pluviométrica do município de Londrina/PR: análise do comportamento, balanço hídrico, probabilidade e tempo de retorno

Este trabalho teve como objetivo verificar a distribuição histórica da pluviometria do município de Londrina/PR entre os anos de 1976 a 2020, a fim de ter um melhor conhecimento de sua disponibilidade hídrica. Para isto, foram utilizadas análises estatísticas descritivas (por exemplo, média, mínimo, máximo, mediana e outros), Índice Padronizado de Precipitação (SPI), Balanço Hídrico Simplificado e Climatológico de Thornthwaite, Probabilidade e Tempo de Retorno pelo Método de Kimbal. Constatou-se, a partir da série histórica analisada, que Londrina apresenta total médio precipitado de 1658,4 mm/ano. Por sua vez, o período médio de maior concentração das chuvas ocorre entre os meses de outubro a fevereiro, sendo o janeiro que apresentou a maior magnitude pluviométrica de 550,7 mm no ano de 2005, com probabilidade de ocorrência de 2%. Destaca-se que o ano de 1980 foi o ano com maior valor de precipitação para a série histórica, com total médio de 2636,3 mm. Por outro lado, os anos 1985 e 2020 apresentaram a menor média anual de precipitação com 1058 e 1090 mm, respectivamente. Ainda foi possível comprovar que de modo geral há uma predominância de eventos chuvosos normais, com SPI oscilando entre +1,0 e -1,0. Sabendo que a pluviosidade é um dos fatores mais importantes para definição do clima de uma região, os dados aqui analisados devem subsidiar a criação de estratégias que visam o planejamento de atividades ambientais e socioeconômicas a fim de auxiliar no gerenciamento e utilização mais eficiente dos recursos hídricos.Palavras-chave: disponibilidade hídrica, padrão climático, mudança temporal, déficit hídrico. Rainfall distribution in the municipality of Londrina/PR: behavior analysis, water balance, probability, and return period A B S T R A C TThis study aimed to verify the historical distribution of rain in Londrina/PR for the period 1976 to 2020 for a better understanding of water availability. Thus, were used descriptive statistical analysis (e.g., mean, minimum, maximum, median, and others), Standardized Precipitation Index (SPI), Thornthwaite's Simplified and Climatological Water Balance, Probability, and Return Period by the Kimbal method. According to the analyzed historical series, it was found that Londrina has an average total rainfall of 1658.4 mm/year. In turn, the middle period with the highest concentration of rain occurs between October and February, with January having the highest rainfall magnitude of 550.7 mm in 2005, with a probability of occurrence of 2%. It is noteworthy that 1980 had the highest precipitation value for the historical series, with an average total of 2636.3 mm. However, 1985 and 2020 had the lowest average annual rainfall, with 1058 and 1090 mm, respectively. It was still possible to prove that, in general, regular rainy events are predominant, with SPI oscillating between +1.0 and -1.0. Knowing that rainfall is one of the most critical factors for defining the climate of a region, the data analyzed here should support the creation of strategies aimed at planning environmental and socioeconomic activities to assist in the management and more efficient use of water resources.Keywords: water availability, climate pattern, temporal change, water deficit.

Variability in growth-determining hydraulic wood and leaf traits in Melia dubia across a steep water availability gradient in southern India

In India, short-rotation plantations have increasingly been promoted over the last decades in response to altered forest management policy and increased wood demand. Understanding how short-rotation forest species coordinate fast growth with water demand and carbon investment will help improving management decisions.We investigated the intra-specific variability in growth performance, leaf traits, and wood anatomical and derived hydraulic properties in 31 Melia dubia (Meliaceae) plantations along a steep rainfall gradient from 450 to 1,700 mm yr−1, and addressed the role of different irrigation practices and soil nutrient availability.We found water supply and soil nutrient status to have a dominant influence on the aboveground biomass increment (AGBI) of M.dubia. AGBI was higher at irrigated sites with a less negative climatological water balance (i.e. with lower rainfall) and at sites with higher soil phosphorus availability. Stem wood anatomical traits associated with the water transport capacity mirrored the patterns in AGBI. At sites with higher water and soil phosphorus availability, the xylem was composed of larger vessel diameters and lower vessel densities. However, both branch wood anatomical traits and leaf traits including the leaf-to-sapwood area ratio were largely independent of water availability and soil conditions.We conclude that a high stem hydraulic efficiency determined by large xylem vessels is a prerequisite for high aboveground productivity, and that the growth of M. dubia may often be phosphorus-limited. Short-rotation plantations with M.dubia will therefore clearly benefits from continuous irrigation in regions that receive annual precipitations substantially below 1,000 mm yr−1. This highlights the potential to increase yields in this important short-rotation forest species by improving irrigation and fertilization protocols.

Trends in pluviometric precipitation and climatic water balance in the hydrographic region of Paraguaçu – BA

Trend analysis of hydroclimatic data is essential in the development of water resources management, as it can envisage changes in the pattern of behaviour, helping develop strategies for adaptation in the face of imminent climate change. This study aimed to investigate possible annual and seasonal trends in rainfall and climatological water balance in the hydrographic region of Paraguaçu - BA. From the historical series of precipitation, deficiency and water surpluses, between 1989 and 2018, two analysis scenarios were conducted: the first to verify the annual and seasonal trends of each station, using the traditional Mann-Kendall (MK) methods and Sen’s estimator; and the second for each sub-region of Paraguaçu, by comparing MK with the Innovative Trend Analysis (ITA). The results of the annual series, regardless of the methodology adopted, point to negative trends in rainfall, positive trends in deficit and negative trends in water surplus. Seasonally, in the autumn and winter seasons, generally considered to be drought, there were more trends of increasing rainfall and decreasing water deficiency. A comparison between the MK and ITA models showed that both have similar results for indicating trends in the sub-regions of Paraguaçu. However, the ITA has shown a higher number of significant trends.

Climatological water balance and climate classification of thornthwaite and mather for benin, west Africa, in 1970-2015 period

The climate is described by the predominant atmospheric conditions in a particular region and influences several human activities. In agriculture, water availability defines the growth and yield of crops and can be obtained by the water balance. The climate classification also aids to identify suitable areas for agricultural crops. Thus, the aim of this work was to elaborate the water balance and perform the climate classification through the method of Thornthwaite and Mather (1955) for six weather stations (Bohicon, Cotonou-Airport, Kandi-Airport, Natitingou, Parakou-Airport and Savè) located in Benin, Western Africa. For the execution of this work, monthly series of precipitation and potential evapotranspiration from 1970 to 2015 were used. Once the monthly water balance of the six seasons was elaborated, it was observed that the rainy (dry) period decreases (increases) from the coast (Cotonou-Airport) to the north of Benin (Kandi-Airport) and, coincides with Boreal summer and part of autumn (Boreal winter and part of spring). Regarding the climate classification, the Cotonou-Airport station was characterized as Subhumid Megathermal climate with moderate winter deficit (C2wA’a’); the stations of Bohicon and Savè presented similar climate classification with Subhumid Dry Megathermal climate with low or without water surplus (C1dA’a’); Natitingou with Subhumid Dry climate Megathermal with large summer surplus (C1s2A’a’); Parakou-Airport with Subhumid climate Dry Megathermic with moderate summer surplus (C1sA’a’) and, Kandi-Airport presented Semi-arid Megathermal climate with moderate summer surplus (DsA’a’). In Benin, subsistence and rainfed farming showed greater risk in the north of the country due to the decrease in the rainy season and the water surplus from the coast (south) to the north of the country, with the increase in aridity.

BALANÇO HÍDRICO CLIMATOLÓGICO E CLASSIFICAÇÃO CLIMÁTICA PARA O MUNICÍPIO DE PARANAVAÍ, PARANÁ

The study of climatic conditions of Paranavaí region is necessary due to its importance in the national agricultural scenario. The study aimed to calculate the climatological water balance (CWB) as well as performing the climate classification by the method of Thornthwaite e Mather for the municipality of Paranavaí, Paraná. Data from a historical series from 1975 to 2018 were used. For the calculation of the CWB was adopted the value of 100 mm for the available water capacity (AWC). The municipality studied presentes na annual average of 1523,8 mm precipitation and 1090,62 evapotranspiration. The municipality presented a trend climate o fone month of water deficiency (August) and eleven months of water excess (Setember to July). Regarding climate classification, was found C1dA’a’ climate, characterized as a mesothermic climate, with little or no water deficiency.

Climate variables on the hydrographic basin of Uruçuí Preto River – Piauí, Brazil subsidies for the management of water and agricultural resources

The knowledge of the climatic characteristics of the hydrographic basins, especially regarding the temporal and spatial distribution of rainfall, the relative humidity of the air and the maximum, minimum and average temperatures of the air, which offer important subsidies to the management of water resources and agriculture. The irregular distribution of rainfall indicates instability in the entry of water into the hydrological system, exercising control over water availability in time and space, the relative humidity of the air influences animal and plant behaviors and the amount of water available in the atmosphere. The temperature, on the other hand, influences the evapotranspiration rates, indicating the energy availability of the environment and, consequently, the environmental water demand. The work presents characteristics of the hydrographic basin of the Uruçuí Preto River (BHRUP), in terms of rainfall, relative humidity, temperature, climatological water balance and climatic regimes. The graphs of annual behavior and seasonal regimes elaborated for 25 pluviometric stations distributed in the interior and around the basin, most of them in operation since the 1960s, followed by the elaboration of average isoietas charts and the one of the rainiest semester, relative humidity of the air, isotherms of the maximum, minimum and average temperatures, and of the letters of potential evapotranspiration, real evaporation and water deficit. The climatic types were appreciated due to the influence of the habitual behavior of the atmosphere on the potential and real environmental demand for water and also on the anthropic demand. The Thornthwaite (1948, 1953) climate system was used, based on the comparison between potential evapotranspiration and rainfall.

Pluviometric variability, water balance and risk of dry spells in the basin of Paraná River III, Brazil

For the agriculture context, the water balance and precipitation analysis are essential for planning and decision-making. The objective of this work was to carry out the analyse of pluviometric variability, climatological water balance (CLIMWB) and the occurrence of dry spells in the Basin of Paraná River III, Paraná State, Brazil. For this purpose, 43 meteorological data from 43 stations, from 1976 to 2018, were used. Geoprocessing techniques were applied to regionalize rain data, in addition to box plots and probabilities to analyze precipitation and the occurrence of dry spells. A signficant precipitation variability was identified with regional and temporal discrepancies. Despite the Basin of Paraná River III is a rainy region in the Paraná State, the occurrence of dry spells was identified. Periods of 20 to 30 days with no precipitation event in the region they were also frequent, due the annual occurrence risks ranging from 80 to 50 %, respectively. The risk of 40 consecutive days without rain has already proved to be nil. The water balance exhibited sufficient values for agricultural practice with water surplus along the Basin. However, when analyzing dry years, a water deficit of more than 100 mm in a single month can occur.

Climate changes and their influences in water balance of Pantanal biome

Climate change is a major problem for humanity, as it can drastically alter the current climate scenario, affecting mainly agriculture. In the state of Mato Grosso do Sul (MS), agribusiness is the main economic activity representing a large part of the state’s GDP. Therefore, the aim of this study was to evaluate the influence of climate change on the climatological water balance in the Pantanal regions of Brazil. We used a 30-year historical series (1987–2018) of air temperature data (Tar, °C) and rainfall (P, mm) from the state of MS; climatic data were collected by the National Aeronautics and Space Administration platform/Prediction of World Wide Energy Resources - (NASA/POWER). Potential evapotranspiration (PET) was estimated using the Camargo (1971) method. The water balance (WB) was calculated using the Thornthwaite and Mather (1955) method, with soil water storage capacity equal to 100 mm. We calculated the aridity, hydric, and moisture indices for all municipalities in MS, and later classified according to Thornthwaite (1948). The scenarios used were based on the (IPCC 2014) projections. Air temperatures in the MS ranged from 22.5 to 27.6 °C in the current scenario; rainfall and PET have an average of 1400 mm annual−1 and 1188 mm annual−1, respectively. The WB of the state of MS has an EXC and DEF of 197.7 mm annual−1 and 64.2 mm annual−1, respectively. The predominant climatic type is C2 - subhumid. The highest values for SWS and EXC occur in scenarios S5, S10, S15, and S20, which are the most moisture scenarios. The highest DEF occurred in scenarios S1, S11, S16, and S21; these scenarios showed the driest climatic types. The northwestern region of the state, where the Pantanal is located, was the driest. In scenario S21, the climate of the state has a drastic change that makes several crops in the MS unfeasible, thus negatively influencing the fauna and flora of the Pantanal biome.

Desertification susceptibility over Rio de Janeiro, Brazil, based on aridity indices and geoprocessing

AbstractDesertification is a serious threat to human development and sustainability. This process is characterized by land degradation over areas with dry sub‐humid, semi‐arid and arid climate. In this work, climate susceptibility to desertification was identified for the state of Rio de Janeiro (SRJ), Brazil, the third most populated state in the country. The state is characterized by complex topography, and diverse climate and land uses. Two formulations for the aridity index were used: Ia, defined by Thornthwaite (1948, Geographical Review, 38(1), 55–94) and Penman (1953, Horticultural Congress, 2, 913–924), and D, a modification of Ia by Hare (1983, Climate and Desertification: A Revised Analysis, Geneva: World Meteorological Organization). Both estimates of the aridity require annual rainfall and potential evapotranspiration, which were calculated from the climatological water balance using times series of rainfall and air temperature (1961–2010) from 98 stations over the SRJ. Annual rainfall, evapotranspiration, water deficit and the aridity indices were then spatially interpolated over a 5 × 5‐km grid using a spline tension method. Both indices agree on the driest regions of the SRJ: Norte and Baixada Litorânea, near the northern coast, both under sub‐humid and semi‐arid climate. The index Ia indicated susceptibility to desertification over 2,305 km2 on the Norte and Baixada Litorânea regions, which correspond to 5% of SRJ area; similarly, the index D classified a smaller area over the Norte region under desertification (431 km2). These subregions, among the others also considered in this study, are of great importance for the agricultural, forestry and tourism industries and contribute immensely to the economic development of the state. Hence, the evaluation of susceptibility to desertification in those areas is essential to help prevent further land degradation and support policies formulation on long‐term sustainable management of land and water resources, especially under regional and global climate change scenarios. The methodology used in this work can be applied to studies of desertification in other regions of the world.

ANÁLISE MULTITEMPORAL DO CLIMA URBANO EM PALMAS, ESTADO DO TOCANTINS –BRASIL

The urban climate changes, caused by intense urban densities, result in loss life quality. Therefore, it becomes increasingly necessary to know the dynamics climatic of a given region in search of strategies to promote socio-environmental quality. The present work aimed to analyze the temporal space variations of the urban climate and the implications of water availability and NDVI in urban heat islands. For this purpose, we adopt as case study the municipality of Palmas - Tocantins. In a first moment, the climatological characterization of the study area through the climatological water balance proposed by Thornthwaite and Mather (1955) was carried out. Then the terrestrial surface temperature (LST) and Normalized Difference Vegetation Index (NDVI) were calculated by means of multispectral images of the LANDSAT7 and LANDSAT8 satellites and GIS software. From the climatic water balance, it was possible to verify indices characteristic of the tropical climate as well as the climatic dynamics of the region. We observed small surface heat islands diagnosed by means of satellite imagery in the urban environment with a magnitude of up to 15 ° Celsius in relation to the nearby rural areas, especially in the drier periods. We also confirmed the importance of green areas in the mitigation of land temperatures.

Direct Versus Indirect Tree Ring Reconstruction of Annual Discharge of Chemora River, Algeria

Annual river discharge is a critical variable for water resources planning and management. Tree rings are widely used to reconstruct annual discharge, but errors can be large when tree growth fails to respond commensurately to hydrologically important seasonal components of climate. This paper contrasts direct and indirect reconstruction as statistical approaches to discharge reconstruction for the Chemora River, in semi-arid northeastern Algeria, and explores indirect reconstruction as a diagnostic tool in reconstruction error analysis. We define direct reconstruction as predictions from regression of annual discharge on tree ring data, and indirect reconstruction as predictions from a four-stage process: (1) regression of precipitation on tree rings, (2) application of the regression model to get reconstructed precipitation for grid cells over the basin, (3) routing of reconstructed precipitation through a climatological water balance (WB) model, and (4) summing model runoff over cells to get the reconstructed discharge at a gage location. For comparative purposes, the potential predictors in both modeling approaches are the same principal components of tree ring width chronologies from a network of drought-sensitive sites of Pinus halepensis and Cedrus atlantica in northern Algeria. Results suggest that both modeling approaches can yield statistically significant reconstructions for the Chemora River. Greater accuracy and simplicity of the direct method are countered by conceptual physical advantages of the indirect method. The WB modeling inherent to the indirect method is useful as a diagnostic tool in error analysis of discharge reconstruction, points out the low and declining importance of snowmelt to the river discharge, and gives clues to the cause of severe underestimation of discharge in the outlier high-discharge year 1996. Results show that indirect reconstruction would benefit most in this basin from tree ring resolution of seasonal precipitation.

Köppen-Geiger and Camargo climate classifications for the Midwest of Brasil

There is a wide variety of climates on the planet’s surface, and climate classifications are tools for delimiting and describing prevailing climate types. Koppen classification relates types of climate to types of vegetation, while Camargo classification seeks to map climatic types based on thermal and water factors. In Brazil, the Midwest region is a major agricultural producer but still lacks detailed climate information. In this sense, we aimed to compare Koppen and Geiger (1928) with Camargo (1991) methods for climate classification in the Midwest of Brazil. For this purpose, we used data on daily global solar radiation; mean, maximum, and minimum air temperature; relative humidity; wind speed; and precipitation from 2160 weather stations, which were obtained from the NASA/POWER platform. Components of normal climatological water balance were calculated using the Thornthwaite and Mather (1955) method, with an available water capacity of 100 mm. Koppen and Geiger (1928) system uses data on mean annual temperature, annual precipitation, coldest month mean temperature, warmest month mean temperature, and driest month precipitation. The method of Camargo (1991), modified by Maluf (2000), uses the following meteorological elements: mean annual temperature, coldest month mean temperature, annual water surplus and deficit, and water deficit months. The similarity between classification methods was verified by agglomerative hierarchical clustering and Tukey’s test at 95% reliability. The most predominant climate class according to Camargo (1991) was TR-UMi (humid tropical climate), representing 33.63% of the entire territory of the Midwest of Brazil. According to Koppen and Geiger (1928), six climate types were observed in the Midwest region, with a predominance of class Aw (tropical climate with dry winter), representing 58.50% of the entire region. While Koppen and Geiger (1928) showed a macroscale scope, Camargo (1991) classification had a mesoscale approach. The latter was more suitable for agricultural purposes, mainly because it provided information on prevailing water conditions in the region.