Wildland fires are increasing in both severity and intensity leading to severe and lasting biogeochemical effects on soil. The CZU lightning complex started on August 16th, 2020, and burned 86,509 acres causing severe social and ecological damage. To better understand the impact of fire on soil properties at the landscape scale, we created a digital soil mapping model with the inclusion of remotely sensed burn severity covariates. We combined a raster-stack of environmental covariates with rasters for fire severity and soil samples, to disentangle the relative contribution of fire to the spatial distribution of soil properties in the recently burned Little Creek watershed in Santa Cruz, Ca. Soils were sampled via a conditional Latin hypercube sampling design and analyzed for soil health and soil Fe/Al-oxide mineralogy. To ascertain the relative contribution of remotely sensed fire severity covariates and standard digital soil mapping covariates (e.g. SCORPAN factors) to explain the variance in post-fire soil properties, we deployed multi-linear regression and random forest modeling. We report that remotely sensed indicators of fire severity explained the variance of Ntotal, Caex, pH, oxalate extractable P, NO3-, and NH4+ in both the MLR and RF models at the watershed scale. The inclusion of rasters of fire effects improved the description of target soil property variance, in concert with more traditional raster-based proxies for the soil forming factors, indicating that fire helps explain the spatial variability of these soil properties in recently burned post-fire landscapes. Furthermore, we report that an increase in remotely sensed fire severity led to an increase in sorbed P (as measured via oxalate extractable P), suggesting a potentially unreported change to post-fire soil P dynamics. Results inform remotely sensed assessment of fire induced changes to soil properties at the landscape scale.

No description available.

One of prospective procedures of absorbing thermal energy and releasing it during the required time is the application of phase change materials known as PCMs in building envelopes. High thermal energy storage (TES) materials has been a technology that effects the energy efficiency of a building by contributing in using onsite resources and reducing cooling or heating loads. Currently, many TES systems are emerging and contributing in building assemblies, however using an appropriate type of TES in a specific building and climate requires an in-depth knowledge of their properties. This research aims to provide a thorough review of a broad range of thermal energy storage technologies including their potential application in buildings. Subsequently, a comparative study and simulation between a basecase and an optimized model by PCM is thoroughly considered to understand the effect of high thermal storage building's shell on energy efficiency and indoor thermal comfort. Specifically this study proposes that the incorporation of PCM into glazing system as a high thermal capacity system will improve windows thermal performance and thermal capacity to varying climatic conditions. The generated results by eQUEST energy modeling software demonstrates approximately 25% reduction in cooling loads during the summer and 10% reduction in heating loads during the winter for optimized office building by PCM in hot arid climate of Arizona. Besides, using PCM in glazing system will reduce heat gain through the windows by conduction phenomenon. The hourly results indicates the effect of PCM as a thermal energy storage system in building envelopes for building's energy efficiency and thermal regulation. However, several problems need to be tackled before LHTES can reliably and practically be applied. We conclude with some suggestions for future work.

In contrast to composites and woven fabrics, nonwoven materials have a unique web structure, which is composed of randomly oriented fibres bonded in a pattern by mechanical, thermal or chemical techniques. The type of nonwovens studied in this research is a thermally bonded one with polymer-based bicomponent fibres. Such fibres have a core/sheath structure with outer layer (sheath) having a lower melting temperature than that of the core. In thermal bonding of such fibres, as the hot calender with an engraved pattern contacts the fibrous web, bond points are formed thanks to melting of the sheath material. Molten sheath material acts as an adhesive while core parts of the fibres remain fully intact in the bond points. On the other hand, web regions, which are not in contact with the hot engraved pattern, remain unaffected and form the fibre matrix that acts as a link between bond points. With two distinct regions, namely, bond points and fibre matrix, with different structures, nonwovens exhibit a unique deformation behaviour. This research aims to analyse the complex mechanical behaviour of thermally bonded bicomponent fibre nonwoven materials using a combination of experimental and numerical methods. A novel approach is introduced in the thesis to predict the complex mechanical behaviour of thermally bonded bicomponent fibre nonwovens under various threedimensional time-dependent loading conditions. Development of the approach starts with experimental studies on thermally bonded bicomponent fibre nonwovens to achieve a better understating of their complex deformation characteristics. Mechanical performance of single bicomponent fibres is investigated with tensile and relaxation tests since they are the basic constituents of nonwoven fabrics. The fabric microstructure, which is one of the most important factors affecting its mechanical behaviour, is examined with scanning electron microscopy and X-ray micro computed tomography techniques. At the final part of experimental studies, mechanical response of thermally bonded bicomponent fibre nonwovens is characterised with several mechanical tests. (Continues...).

Atmospheric plasma sprayed (APS) thermal barrier coatings (TBCs) are commonly used for thermal protection of components in modern gas turbine application such as power generation, marine and aero engines. TBC is a duplex material system consisting of an insulating ceramic topcoat layer and an intermetallic bondcoat layer. TBC microstructures are highly heterogeneous, consisting of defects such as pores and cracks of different sizes which determine the coating's final thermal and mechanical properties, and the service lives of the coatings. Failure in APS TBCs is mainly associated with the thermo-mechanical stresses developing due to the thermally grown oxide (TGO) layer growth at the topcoat-bondcoat interface and thermal expansion mismatch during thermal cycling. The interface roughness has been shown to play a major role in the development of these induced stresses and lifetime of TBCs.The objective of this thesis work was two-fold for one purpose: to design an optimised TBC to be used for next generation gas turbines. The first objective was to investigate the relationships between coating microstructure and thermal-mechanical properties of topcoats, and to utilise these relationships to design an optimised morphology of the topcoat microstructure. The second objective was to investigate the relationships between topcoat-bondcoat interface roughness, TGO growth and lifetime of TBCs, and to utilise these relationships to design an optimal interface. Simulation technique was used to achieve these objectives. Important microstructural parameters influencing the performance of topcoats were identified and coatings with the feasible identified microstructural parameters were designed, modelled and experimentally verified. It was shown that large globular pores with connected cracks inherited within the topcoat microstructure significantly enhanced TBC performance. Real topcoat-bondcoat interface topographies were used to calculate the induced stresses and a diffusion based TGO growth model was developed to assess the lifetime. The modelling results were compared with existing theories published in previous works and experiments. It was shown that the modelling approach developed in this work could be used as a powerful tool to design new coatings and interfaces as well as to achieve high performance optimised morphologies.

O desempenho das Máquinas de Medir a Três Coordenadas (MM3Cs) fica limitado por diversos fatores, que atuam de maneira conjunta gerando os denominados erros volumétricos. Para a temperatura de 20ºC os erros geométricos podem ser considerados constantes, uma vez que variam muito lentamente com o tempo. Porém, se a temperatura é alterada estes erros mudam em grandeza e comportamento, gerando os denominados erros térmicos. Alguns trabalhos têm sido desenvolvidos com o objetivo de estudar e modelar os erros térmicos, porém os resultados alcançados são, ainda, incipientes. Este trabalho apresenta o equacionamento das componentes do erro volumétrico das MM3Cs considerando as influências térmicas. A medelagem foi aplicada a uma MM3C do tipo \"Ponte Móvel\" e combina transformações homogêneas, técnicas de regressão e mínimos quadrados. As grandezas dos erros geométricos e das variações termicamente induzidas destes erros foram coletadas utilizando-se do interferômetro laser, do esquadro mecânico, do nível eletrônico, etc. Os valores das temperaturas foram monitorados através de termopares do tipo T (Cobre-Constantan). Verificou-se que a Máquina não experimenta deformações, além, das provocadas pela livre dilatação dos seus componentes. A partir do modelo proposto foram sintetizadas as componentes do erro volumétrico, os resultados foram discutidos e comparados com aqueles obtidos através da medição de um anel padrão, constatando-se a excelente capacidade do modelo na previsão do erro volumétrico da máquina. No caso, erros da ordem de grandeza de 10 &#956m foram reduzidos em pelo menos 75%, enquanto que para erros maiores que 10 &#956m a eficiência do modelo foi de 90%. / Performance of coordinate measuring machines (CMMs) is limited by numerous factors that operate simultaneously and generate volumetric errors. The most significant portion of the volumetric error is produced by geometric errors. At the temperature of 20ºC, geometric errors can be considered at steady states, once their variation in time is considerably slow. However, if temperature is modified, these errors change in magnitude and behaviour, generating the thermal induced errors. Some work has been developed aiming to study and model the thermal errors, but the achieved results are still incipient. This work presents the derivation of the components of the volumetric error considering its thermal influences. The method was employed and applied to moving bridge CMM and combines homogeneous transformation, regression techniques and least squares methods. The magnitudes of the geometric errors and its thermally induced variations were collected by means of a laser interferometer system, mechanical square, electronic level, etc. Temperature data were monitored by means of T-type thermocouples (copper-constantan). It was verified that the CMM was not susceptible to deformations other than the ones due to the dilatation of its components. From the proposed model, the components of volumetric error were synthesized; the results were discussed and compared to the ones obtained from the measurement of a ring plug, observing the outstanding ability of the model to predict the volumetric error of the machine. Errors of 10 &#956m in magnitude were reduced in at least 75%, whilst errors greater than 10 &#956m, presented a reduction efficiency of 90%. It was verified that the CMM was not susceptible to deformations other than the ones due to the dilatation of its components.

Os padrões de circulação do Atlântico Sudoeste são caracterizados por uma diversidade de massas de água. A presença das correntes associadas ao giro subtropical e a incursão para norte da Corrente Circumpolar Antártica (CCA) determinam extensas regiões de largo gradiente de Temperatura da Superfície do Mar (TSM). Ao mesmo tempo, circulações de mesoescala geram intensos gradientes setorizados, ou reforçam o contraste de larga-escala. Consequentemente, frentes oceânicas de diferentes escalas são formadas ao longo desses gradientes. Quando o vento sopra sobre essas frentes, os fluidos trocam calor e momentum alterando suas propriedades dinâmicas e termodinâmicas. Nesse trabalho visamos caracterizar as alterações no campo de vento superficial que podem ser atribuídas a essas trocas. Para isso, foi aplicado um algoritmo de detecção de frentes em campos de Temperatura da Superfície do Mar (TSM) derivados do conjunto OSTIA. Em situações de escoamento atmosférico sinótico homogêneo, foram calculados o divergente e rotacional do vento medido pelo escaterômetro QuickSCAT ao longo das zonas frontais, bem como suas componentes perpendicular e paralela às frentes. Ao longo de 8 anos mais 96.000 frentes oceânicas foram detectadas, co-localizadas com a disponibilidade de dados de vento dando origem a 40.000 composições. O sistema de coordenadas dessas composições foi rotacionado para que as frentes oceânicas tivessem a mesma orientação. Nós empilhamos as composições em um arranjo 3D e foram obtidas médias das circulações atmosféricas induzidas. As perturbações médias obtidas indicaram que há convergência do vento quando este sopra do lado quente para o lado frio da frente com a frenagem do escoamento. De forma oposta, há divergência e aceleração do vento quando este sopra no sentido oposto. Nós identificamos alterações locais no rotacional do campo de vento capazes de induzir o bombeamento de Ekman no oceano. Esse processo pode gerar mecanismos de retroalimentação no sistema. Nossos resultados corroboram o de diversos estudos sobre o tema presentes literatura. / The southwest Atlantic circulation patterns are characterized by a diversity of water masses. The presence of currents associated with the subtropical gyre and the northward incursion of Antarctic Circumpolar Current (ACC) determine extensive regions of strong sea surface temperature gradient (SST). At the same time, mesoscale circulations generate intense local gradients, or reinforce the large-scale contrast. Consequently, oceanic fronts are formed along these gradients on different scales. When the wind blows over these fronts, the fluids exchange heat and momentum, and that changes their dynamic and thermodynamic properties. In this work we aim to characterize the changes in the surface wind field that might be attributed to these exchanges. To do it, a frontal detection algorithm was applied to the SST field derived from OSTIA set. We selected situations of synoptic homogeneous atmospheric flow and calculated the divergent and rotational wind, in addition to its perpendicular and parallel components to the oceanic fronts. We used wind measurements recorded by the QuickSCAT scatterometer along the frontal zones. More than 96,000 oceanic fronts were detected along 8 years of data. We matched them to available wind data and formed more than 40,000 SST-WIND compositions. The coordinate system of these compositions was rotated so that all oceanic fronts have the same horizontal orientation. We piled up the compositions in a 3D array and the temporal mean of the induced circulations was calculated. The average disturbance obtained indicated that there is wind convergence when it blows from the warm side of the front to the cold side because the flow is slowed down. Conversely, there is wind divergence when it blows in the opposite direction due to speeding up flow. We identified local changes in wind field curl capable of inducing Ekman pumping over the ocean. This process can generate feedback mechanisms in the system. Our results were consistent with the literature.

Ametistas naturais brasileiras foram estudadas através das técnicas de Absorção Óptica (AO), Ressonância Paramagnética Eletrônica (RPE) e Corrente de Despolarização Termicamente Estimulada (CDTE).O espectro de AO apresentou três picos principais na região espectral do visível (10500, 18600 e 28200cm POT.-1) e um enorme pico na região do ultravioleta (45000cm POT.-1) atribuídos ao ferro em diferentes estados de valência. A presença de centros OH POT.- foi observada na região do infravermelho através das bandas em 3440 e 3580cm POT.-1. O espectro de RPE, operando na banda X, exibe um conjunto de linhas centrado em 2000G, um pico intenso em 3000G e quatro picos pequenos em 4000, 5000, 6000 e 7000G, quando o campo magnético encontra-se paralelo a um dos eixos cristalograficamente equivalentes. Quando o campo magnético encontra-se paralelo ao eixo c do cristal, o espectro de RPE revela um conjunto de linhas centrado em 2000G, dois picos intensos próximos a 5000G e um pico pequeno em 6800G. Amostras em pó apresentam uma banda larga centrada em 3400G. Tratamentos térmicos mostram uma redução gradativa desta banda com o aumento do tempo de tratamento térmico e uma redução mais rápida para temperaturas maiores. Sabe-se que os centros de cor nas ametistas são produzidos pela ação de radiação ionizante natural sobre os centros precursores que surgem da substituição do Si POT.4+ pelo Fe POT.3+ na estrutura do quartzo-alfa. Esses centros de Fe POT.3+ não se distribuem igualmente entre os sítios equivalentes no cristal natural e são responsáveis pelas características dominantes do espectro de RPE. O espectro de CDTE obtido da polarização de uma amostra em 1000V apresenta uma banda em 215K, que vem a ser a composição de três bandas de menor intensidade (185, 200 e 214K) e uma banda única em 260K. Foi confirmado o caráter dipolar dessas bandas. Tratamentos térmicos efetuados a diferentes temperaturas mostram ) um decaimento de área total e uma redução da intensidade das bandas mais acentuadas para temperaturas maiores. Iluminação ultravioleta restaura parcialmente o espectro de CDTE e demonstra o crescimento de uma banda na região da temperatura ambiente. Devido ao comportamento semelhante dos espectros de CDTE e de RPE, o sendo Fe POT.3+ um elemento presente em grande quantidade nas amostras estudadas, acredita-se que o centro de dipolo responsável pelas bandas de CDTE observadas, seja do Fe POT.3+ substituindo um Si POT.4+ próximo a um O POT.- ou a um OH POT.-, e que as diferentes posições dos picos devem-se à população desigual do Fe POT.3+ substitucional nos sítios cristalograficamente equivalentes do cristal. / Brazilian natural amethyst samples have been studied through Optical Absorption (AO), Electron Paramagnetic Resonance (EPR) and Thermally Stimulated Depolarization Current (TSDC) Techniques.The AO spectrum shows three main peaks in the visible region (10500, 18600 e 28200cm POT.-1) and a huge peak in the ultraviolet region (45000cm POT.-1). All these peaks were attributed to iron in different valence states. The presence of centros OH POT.- centres have been observed through the bands at 3440 e 3580cm POT.-1in the infrared.The EPR spectrum shows a set of lines centered at 2000G, an intense peak at 3000G and four small peaks at 4000, 5000, 6000 and 7000G, when the magnetic field is parallel to one of crystallographically equivalents sites. When the magnetic field is parallel to the crystal c-axis, the EPR spectrum shows a set of lines centered at 2000G, two high peaks near 5000G and a small peak at 6800G. Powder samples presents a broad band centered in 3400G. Thermal treatments reduce this band for increasing thermal treatments time intervals. The reduction increases for high temperatures. It is well known that colour centres in amethysts are produced after natural ionizing radiation and that the centres are provided with the substitution of Fe POT.3+ for Si POT.4+ in quartzo-alfa structure. The Fe POT.3+ centres are not equally distributed among the equivalent sites of the natural crystal and are responsible for the dominant features of the EPR spectra. The obtained TSDC spectrum for polarization at 1000V shows a broad band at 215K, resulting from the superposition of three bands at 185, 200 and 214k and another band at 260K. The dipole origin of these bands has been confirmed. Thermal treatments at different temperatures produce a decay of the total area and a reduction of the bands intensities. Thermal reduction increases for higher temperatures. Ultraviolet illumination partially restores the TSDC spectrum. A new band appears at room temperature. Due to the similar behavior of the TSDC and EPR spectra and taking into account that the Fe POT.3+ is the most prominent impurity in the studied samples, we believe that the dipoles are substitutional Fe POT.3+ near O POT.- or an OH POT.- and that the different position of the peaks, very near, but not the same, are in crystallographically equivalent sites.

Les travaux présentés dans ce mémoire se concentrent sur la compréhension, la description et enfin la modélisation de la décomposition des matériaux d’aménagement ou d’ameublement d’usage courant (principalement des polymères naturels et de synthèse) sous l’effet de la chaleur. Ce champ de la recherche n’est pas nouveau, et de nombreux modèles existent à ce jour (le plus souvent des modèles d’Arrhénius associés à diverses fonctions cinétiques). Toutefois, contrairement aux développements liés à la description de la cinétique chimique en phase gazeuse, la plupart des modèles exploités à ce jour pour la phase solide souffrent généralement d’une justification théorique insuffisante. De plus, des essais, en particulier à petite échelle, laissent apparaître des comportements qui, au-delà de ne pas être prédits par les modèles existant, viennent de surcroît invalider certaines de leurs hypothèses sous-jacentes. Le contexte des travaux est plus précisément celui de la décomposition anaérobie des solides, à petite échelle, pour des masses de l’ordre du milligramme, pour se concentrer à la fois sur la cinétique de perte de masse et, dans une moindre mesure, sur les transferts thermiques dans la phase condensée. Le travail est articulé autour de trois volets principaux qui forment chacun un chapitre du présent ouvrage. Le premier concerne la réalisation de nombreux essais à l’analyseur thermogravimétrique (ATG), sur la base de plans d’expérience. Le but est d’une part de déterminer les variables d’influence de la décomposition thermique et, d’autre part, d’identifier les écarts de comportement par rapport aux prédictions de certains modèles existant dans la littérature. Le résultat majeur de cette campagne est l’absence de convergence en masse des essais, même pour des masses expérimentales très faibles. De même, les effets de la vitesse de chauffage et de la dilution en phase solide ont été explorés, mettant ainsi en avant des comportements très éloignés des prédictions théoriques. Le second concerne la modélisation de la décomposition thermique d’un matériau soumis un essai à l’analyseur thermogravimétrique et la mise en évidence des problématiques liées aux transferts thermiques au sein du matériau. Il a été démontré que les conditions aux limites de Dirichlet, usuellement utilisées pour décrire ce dispositif, ne sont pas adaptées pour reproduire les spécificités liées au dispositif expérimental. Le troisième volet a consisté à construire un modèle cinétique issu d’hypothèses liées à la phase solide. Ce modèle est basé dans un premier temps sur les travaux d’Eyring concernant la théorie du complexe activé. Par la suite, l’exploitation du formalisme thermodynamique lié au complexe activé a permis de proposer une formulation nouvelle, dite « hors approximation d’Ellingham », pour décrire la décomposition des matériaux sous l’effet de la température. Ce modèle a été comparé à deux modèles usuels, dits (A, E, 1) et (A,E,n), et conduit à de meilleures modélisations pour les mécanismes mono-réactionnels. Enfin, les perspectives de ce travail concernent, en premier lieu, une meilleure caractérisation des conditions aux limites thermiques au sein d’un analyseur thermogravimétrique, afin de reproduire numériquement les essais réalisés. En second lieu, il apparaît comme pertinent d’étendre le modèle développé à des mécanismes multi-réactionnels, afin d’augmenter ses capacités prédictives pour les applications visées / The work presented in this thesis focuses on understanding, describing and finally modelling the degradation, under heat exposure, of commonly used furnishing materials (mainly natural or synthetic polymers). This is not a new research field, as many models exist nowadays (such as Arrhenius models associated with varied kinetics functions). However, unlike for development related to gas phase chemical kinetics, most current solid phase chemical kinetics related models suffer from insufficient theoretical backgrounds. Moreover, laboratory experiments, more precisely small scale ones, reveal some behaviours, that are not only unpredicted by current model, but also invalidate some of the underlying assumptions these models are based on. This work context is more precisely related to solid anaerobic decomposition, at small scale, for mass in the range of one milligram, in order to focus on both mass loss kinetics and, to a lesser extent, on thermal transfer in solid phase. This work was structured into three main sections, each of them being a chapter of this thesis. First part concerns numerous experiments based on experimental plans and performed with a thermogravimetric analyzer (TGA). This aims at, on the one hand, determining most influent variables on thermal decomposition, and, on the other hand, identifying behaviour discrepancies between experimental data and predictions of current models available in the literature. Test campaign main result is that there is no mass convergence with TGA, even for very low masses. In addition, the effect of both heating rate and solid phase dilution were explored. This led to some behaviours significantly different from theoretical predictions. Second part concerns the modelling of material thermal degradation in a TGA analysis. It also highlights problems related to heat transfer inside solid material. It is demonstrated in this work that Dirichlet boundary conditions, which are usually used to describe TGA device, are not adequate to reproduce such experimental specificities. Third and last part is dedicated to the elaboration of a kinetic model relying on assumptions specific to the solid phase. First and foremost this model is on based on Eyring’s work on transition state theory. Then exploring thermodynamic formalism related to transition state allowed the formulation of a new model of thermal degradation called “outside Ellingham assumption”. This model is compared to two commonly used ones, so-called (A, E, 1) and (A, E, n) and led to best prediction for single reaction mechanisms. Finally, the prospects inspired by this work concern, first, a better characterisation of thermal boundary condition in TGA, in order to be able to reproduce experiments by modelling. Secondly, it may be relevant to extend the develop model to multiple reaction mechanisms, in order to increase its predictive capabilities for the targeted applications

Os padrões de circulação do Atlântico Sudoeste são caracterizados por uma diversidade de massas de água. A presença das correntes associadas ao giro subtropical e a incursão para norte da Corrente Circumpolar Antártica (CCA) determinam extensas regiões de largo gradiente de Temperatura da Superfície do Mar (TSM). Ao mesmo tempo, circulações de mesoescala geram intensos gradientes setorizados, ou reforçam o contraste de larga-escala. Consequentemente, frentes oceânicas de diferentes escalas são formadas ao longo desses gradientes. Quando o vento sopra sobre essas frentes, os fluidos trocam calor e momentum alterando suas propriedades dinâmicas e termodinâmicas. Nesse trabalho visamos caracterizar as alterações no campo de vento superficial que podem ser atribuídas a essas trocas. Para isso, foi aplicado um algoritmo de detecção de frentes em campos de Temperatura da Superfície do Mar (TSM) derivados do conjunto OSTIA. Em situações de escoamento atmosférico sinótico homogêneo, foram calculados o divergente e rotacional do vento medido pelo escaterômetro QuickSCAT ao longo das zonas frontais, bem como suas componentes perpendicular e paralela às frentes. Ao longo de 8 anos mais 96.000 frentes oceânicas foram detectadas, co-localizadas com a disponibilidade de dados de vento dando origem a 40.000 composições. O sistema de coordenadas dessas composições foi rotacionado para que as frentes oceânicas tivessem a mesma orientação. Nós empilhamos as composições em um arranjo 3D e foram obtidas médias das circulações atmosféricas induzidas. As perturbações médias obtidas indicaram que há convergência do vento quando este sopra do lado quente para o lado frio da frente com a frenagem do escoamento. De forma oposta, há divergência e aceleração do vento quando este sopra no sentido oposto. Nós identificamos alterações locais no rotacional do campo de vento capazes de induzir o bombeamento de Ekman no oceano. Esse processo pode gerar mecanismos de retroalimentação no sistema. Nossos resultados corroboram o de diversos estudos sobre o tema presentes literatura. / The southwest Atlantic circulation patterns are characterized by a diversity of water masses. The presence of currents associated with the subtropical gyre and the northward incursion of Antarctic Circumpolar Current (ACC) determine extensive regions of strong sea surface temperature gradient (SST). At the same time, mesoscale circulations generate intense local gradients, or reinforce the large-scale contrast. Consequently, oceanic fronts are formed along these gradients on different scales. When the wind blows over these fronts, the fluids exchange heat and momentum, and that changes their dynamic and thermodynamic properties. In this work we aim to characterize the changes in the surface wind field that might be attributed to these exchanges. To do it, a frontal detection algorithm was applied to the SST field derived from OSTIA set. We selected situations of synoptic homogeneous atmospheric flow and calculated the divergent and rotational wind, in addition to its perpendicular and parallel components to the oceanic fronts. We used wind measurements recorded by the QuickSCAT scatterometer along the frontal zones. More than 96,000 oceanic fronts were detected along 8 years of data. We matched them to available wind data and formed more than 40,000 SST-WIND compositions. The coordinate system of these compositions was rotated so that all oceanic fronts have the same horizontal orientation. We piled up the compositions in a 3D array and the temporal mean of the induced circulations was calculated. The average disturbance obtained indicated that there is wind convergence when it blows from the warm side of the front to the cold side because the flow is slowed down. Conversely, there is wind divergence when it blows in the opposite direction due to speeding up flow. We identified local changes in wind field curl capable of inducing Ekman pumping over the ocean. This process can generate feedback mechanisms in the system. Our results were consistent with the literature.