Variação espacial da temperatura de superfície: estudo de caso de dois episódios no município de Viana, Espírito Santo, Brasil, em 2019

<p>Esta pesquisa tem o objetivo de identificar e analisar a variação das temperaturas de superfície do Município de Viana, Espírito Santo, Brasil, por meio de técnicas de Sensoriamento Remoto, em dois episódios, chuvoso e seco, de 2019, bem como relacionar as classes de temperatura com o uso e a cobertura do solo e a morfologia do terreno. Para tanto, foram feitos levantamentos bibliográficos entre livros, teses, dissertações e artigos científicos que discorrem sobre os principais conceitos aqui tratados (Clima, Climatologia Geográfica, Sensoriamento Remoto, Sistemas de Informações Geográficas etc.), aquisição de bases cartográficas (vetoriais e raster) para a elaboração dos mapas e para aplicação de recursos técnicos de geoprocessamento de imagens de satélite. Os resultados mostraram diferenças significativas na variação das temperaturas, mais elevadas nas áreas urbanas comparativamente às áreas de agricultura/pastagens (8°C) e providas de cobertura florestal (9,5°C), tanto no verão quanto no inverno, associadas às propriedades diferenciadas quanto à produção, à propagação e à conservação de calor no ambiente.</p><p><span>Abstract</span></p><p>SPATIAL VARIATION OF SURFACE TEMPERATURE: CASE STUDY OF TWO EPISODES IN THE MUNICIPALITY OF VIANA, ESPÍRITO SANTO, BRAZIL, IN 2019</p><p>This research aims to identify and analyze the variation in surface temperatures in the municipality of Viana, Espírito Santo, Brazil, using Remote Sensing techniques, in two episodes, rainy and dry 2019, as well as to relate the temperature classes with the land use and cover and the terrain morphology. To this end, bibliographical surveys were made between books, theses, dissertations and scientific articles that discuss the main concepts treated here (Clima, Geographic Climatology, Remote Sensing, Geographic Information Systems, etc.), acquisition of cartographic bases (vector and raster) for the preparation of maps and for the application of technical resources for geoprocessing satellite images. The results showed significant differences in the variation of higher temperatures in urban areas compared to areas of agriculture / pasture (8°C) and provided with forest cover (9.5°C) both in summer and in winter associated with different properties as to production, propagation and heat conservation in the environment.</p>

NEW METHOD EVALUATION OF DETAIL MATERIAL AND HEAT FLOWS FOR SINGLE STRING CEMENT CLINKER PLANT

Material flow in each main equipment of a cement clinker plant, which is very useful for controlling the process, is impossible to be measured during operation due to very high temperatures. This paper intends to overcome the difficulties associated with the measurement of these material flow values. This study presents a new method of calculating material flow (gas and solid) in each main equipment of a single string conventional suspension preheater type of a cement clinker plant. Using the proposed method, mass flow rate at a clinker cooler, kiln, suspension preheater (SP) and even each cyclone separator can be calculated with a heat conservation error less than 1 %. With the application of the least square method for solving the overdetermined system of mass and heat conservation equations obtained in the cyclones of SP, the flow of gas and solid materials entering and exiting each cyclone that cannot be measured directly in the operating plant can be approached. Based on the operation temperature data of gas and solid flows monitored in the control room of an Indonesian cement plant as a case study, the mass flow rate of gas and solid entering and exiting as well as separation efficiency of each cyclone can be calculated. The results show that the separation efficiencies of cyclones 1, 2, 3 and 4 are 95 %, 91.89 %, 84.09% and 79.51% respectively. Finally, this study will be very useful by providing data that are impossible to gather by a direct measurement in an operating plant, due to a very high process temperature constraint, for operational control needs, new equipment design, process simulation using computational fluid dynamics (CFD) software and even modification of existing equipment. The proposed method can be applied to all types of modern cement clinker plant configurations, either with or without a calciner including the double strings.

Numerical Study on Performance Optimization of an Energy-Saving Insulated Window

Window energy consumption has become a key factor in designing buildings with optimal energy efficiency. To that end, herein, the use of an energy-saving insulated window (ESIW) is proposed, particularly for winter heat conservation. DeST software was used to evaluate the energy consumption properties of a house with an ESIW-structure window, as well as that of six other window structures currently on the market. The results were subsequently compared. Furthermore, a series of numerical simulations were carried out using Airpak software to investigate the insulation performance of four ESIW models (A, B, C, and D) under different influencing factors. Finally, the response surface method (RSM) was used to obtain the optimal ESIW structure installation conditions and the weight of each factor. The data shows that houses with ESIW-structure windows exhibit a more suitable indoor natural temperature; less heating load, cooling load, and cumulative annual load; and a more feasible price–load ratio than other energy-saving windows. Furthermore, the average temperature gradually decreased in response to decreasing the electric heater power and energy-saving standard, and increasing the heat transfer coefficient (HTC) and window-to-wall ratio (WWR). Thus, as the energy-saving standard (ESS) increases, the importance of the WWR increases in parallel. This study puts forward an HTC prediction formula that is applicable to different conditions. The optimal thermal efficiency conditions consisted of HTC = 1.07 W/m2 × K, WWR = 0.26, and an ESS of 75%. This study demonstrates that the ESIW system has optimal energy-saving properties and broad adaptability and operability, which can be applied in building insulation as a key insulation component.

Social hierarchy reveals thermoregulatory trade-offs in response to repeated stressors

ABSTRACTCoping with stressors can require substantial energetic investment, and when resources are limited, such investment can preclude simultaneous expenditure on other biological processes. Among endotherms, energetic demands of thermoregulation can also be immense, yet our understanding of whether a stress response is sufficient to induce changes in thermoregulatory investment is limited. Using the black-capped chickadee as a model species, we tested a hypothesis that stress-induced changes in surface temperature (Ts), a well-documented phenomenon across vertebrates, stem from trade-offs between thermoregulation and stress responsiveness. Because social subordination is known to constrain access to resources in this species, we predicted that Ts and dry heat loss of social subordinates, but not social dominants, would fall under stress exposure at low ambient temperatures (Ta), and rise under stress exposure at high Ta, thus permitting a reduction in total energetic expenditure toward thermoregulation. To test our predictions, we exposed four social groups of chickadees to repeated stressors and control conditions across a Ta gradient (n=30 days/treatment/group), whilst remotely monitoring social interactions and Ts. Supporting our hypothesis, we show that: (1) social subordinates (n=12), who fed less than social dominants and alone experienced stress-induced mass-loss, displayed significantly larger changes in Ts following stress exposure than social dominants (n=8), and (2) stress-induced changes in Ts significantly increased heat conservation at low Ta and heat dissipation at high Ta among social subordinates alone. These results suggest that chickadees adjust their thermoregulatory strategies during stress exposure when resources are limited by ecologically relevant processes.

Geographic variation in body size of five Australian marsupials supports Bergmann’s thermoregulation hypothesis

Despite a large body of research, little agreement has been reached on the ultimate driver(s) of geographic variation in body size (mass and/or length). Here we use skull length measurements (as a surrogate for body mass) from five Australian marsupial species to test the primary hypotheses of geographic variation in body size (relating to ambient temperature, productivity, and seasonality). We used a revised articulation of Bergmann’s rule, wherein evidence for thermoregulation (heat dissipation or heat conservation) is considered supportive of Bergmann’s rule. We modeled the skull lengths of four Petaurid glider species and the common brushtail possum (Trichosurus vulpecula) as a function of indices of ambient temperature, productivity, and seasonality. The skull length of Petaurus ariel, P. notatus, and the squirrel glider (P. norfolcensis), increased with increasing winter minimum temperature, while that of T. vulpecula decreased with increasing summer maximum temperature. The skull length of P. ariel decreased with indices of productivity, falsifying the productivity hypothesis. Only P. ariel met the hypothesis of seasonality, as skull length increased with increasing seasonality. Thermoregulation was the most consistently supported driver of geographic variation in body size, as we found evidence of either heat conservation or heat dissipation in four of the five species examined. We found the geographic range of the individual species and the climate space in which the species occurred was integral to understanding the species’ responses to climate variables. Future studies should use specimens that are representative of a species’ entire geographic range, encompass a variety of climatic regions, and use consistent methodologies and terminology when testing drivers of geographic variation in body size.

A temperate endotherm trades thermoregulation for self-preservation: stress-induced changes in surface temperature as thermoregulatory trade-offs

Coping with stressors can require substantial energetic investment, and when resources are limited, such investment can preclude simultaneous expenditure on other biological processes. Among endotherms, energetic demands of thermoregulation can be immense, yet whether a stress response is sufficient to induce changes in thermoregulatory investment appears unexplored. We tested the hypothesis that stress-induced changes in surface temperature, a well-documented phenomenon across vertebrates, stem from a trade-off between thermoregulation and stress responsiveness, whereby individuals seek to reduce energetic expenditure on thermoregulation in challenging environments (the "Thermoprotective Hypothesis"). We predicted that surface temperature and dry heat loss of individuals that are resource-limited would fall under stress exposure at low ambient temperatures and rise under stress exposure at high ambient temperatures when compared with non-resource limited individuals. To test our predictions, we exposed Black-capped Chickadees to rotating stressors and control treatments (ndays/treatment = 30; paired treatments) across an ambient temperature gradient whilst remotely monitoring both feeding behaviour and surface temperature. Supporting the Thermoprotective Hypothesis, our results showed that: 1) social subordinates (n = 12), who fed less than social dominants and alone suffered stress-induced declines in mass, displayed significantly larger changes in surface temperature following stress exposure than social dominants (n = 8), and 2) stress-induced changes in surface temperature significantly increased heat conservation at low ambient temperatures, and heat dissipation at high ambient temperatures among social subordinates alone. These results suggest that Black-capped Chickadees adjust their thermoregulatory strategies under stress when resources are limited and support the hypothesis that stress-induced changes in temperature are functionally significant.

Body temperature maintenance acclimates in a winter-tenacious songbird

ABSTRACTFlexibility in heat generation and dissipation mechanisms provides endotherms the ability to match their thermoregulatory strategy with external demands. However, the degree to which these two mechanisms account for seasonal changes in body temperature regulation is unexplored. Here we present novel data on the regulation of avian body temperature to investigate how birds alter mechanisms of heat production and heat conservation to deal with variation in ambient conditions. We subjected Dark-eyed Juncos (Junco hyemalis) to chronic cold acclimations of varying duration and subsequently quantified their metabolic rates, thermal conductance, and ability to maintain normothermia. Cold-acclimated birds adjusted traits related to both heat generation (increased summit metabolic rate) and heat conservation (decreased conductance) to improve their body temperature regulation. Increases in summit metabolic rate occurred rapidly, but plateaued after one week of cold exposure. In contrast, changes to conductance occurred only after nine weeks of cold exposure. Thus, the ability to maintain body temperature continued to improve throughout the experiment, but the mechanisms underlying this improvement changed through time. Our results demonstrate the ability of birds to adjust thermoregulatory strategies in response to thermal cues and reveal that birds may combine multiple responses to meet the specific demands of their environments.

Ambient temperature correlates with geographic variation in body size of least horseshoe bats

Geographic variation in body size is common within many animal species. The causes of this pattern, however, remain largely unexplored in most vertebrate groups. Bats are widely distributed globally owing to their ability of powered flight. Most bat species encounter a variety of climatic conditions across their distribution range, making them an ideal taxon for the study of ecogeographic patterns in body size. Here, we used adult least horseshoe bats, Rhinolophus pusillus, to test whether geographic variation in body size was determined by heat conservation, heat dissipation, climatic seasonality, or primary productivity. We measured body mass and head-body length for 246 adult bats from 12 allopatric colonies in China. We quantified the ecological conditions inhabited by each colony, including mean maximum temperature of the warmest month, mean minimum temperature of the coldest month, temperature seasonality, precipitation seasonality, and annual net primary productivity (ANPP). Body mass and head-body length, 2 of the most reliable indicators of body size, exhibited marked differences between colonies. After controlling for spatial autocorrelation, the mean minimum temperature of the coldest month explained most of the variation in body size among colonies, regardless of sex. The mean maximum temperature, climatic seasonality, and ANPP had limited power in predicting body size of males or females in comparison with mean minimum temperature. These results support the heat conservation hypothesis and suggest adaptive responses of body size to cold climates in cave-dwelling bats.

A History of Thermodynamics: The Missing Manual

We present a history of thermodynamics. Part 1 discusses definitions, a pre-history of heat and temperature, and steam engine efficiency, which motivated thermodynamics. Part 2 considers in detail three heat conservation-based foundational papers by Carnot, Clapeyron, and Thomson. For a reversible Carnot cycle operating between thermal reservoirs with Celsius temperatures t and t + d t , heat Q from the hot reservoir, and net work W, Clapeyron derived W / Q = d t / C ( t ) , with C ( t ) material-independent. Thomson used μ = 1 / C ( t ) to define an absolute temperature but, unaware that an additional criterion was needed, he first proposed a logarithmic function of the ideal gas temperature T g . Part 3, following a discussion of conservation of energy, considers in detail a number of energy conservation-based papers by Clausius and Thomson. As noted by Gibbs, in 1850, Clausius established the first modern form of thermodynamics, followed by Thomson’s 1851 rephrasing of what he called the Second Law. In 1854, Clausius theoretically established for a simple Carnot cycle the condition Q 1 / T 1 + Q 2 / T 2 = 0 . He generalized it to ∑ i Q i / T g , i = 0 , and then ∮ d Q / T g = 0 . This both implied a new thermodynamic state function and, with appropriate integration factor 1 / T , the thermodynamic temperature. In 1865, Clausius named this new state function the entropy S.