Avaliação da variação da temperatura superficial na lagoa rasa de Itapeva mediante a imagens de satélite

The role of temperature in water is fundamental for the community aquatic dynamics once it regulates several processes on different scales. The spatial and temporal variability of water temperature can be assessed by satellite images, which allows a better understanding of ecosystems. In this work, we evaluated the surface temperature variation of Itapeva Lake, located in Rio Grande do Sul, Brazil, between 1985 and 2017, using MOD11A1 product and images Landsat 5, 7 and 8. An homogeneous seasonal variation pattern was identify between the two sensors used. The information provided by MODIS and Landsat has a coefficient R2 = 0.91 and RMSE = 2.32 ° C. The analysis between the Landsat series adjusted data and the original data allowed the smoothing of maximum and minimum temperatures of water, reducing biased records. Water temperature for the summer and autumn months increases, while for the winter season the regime decrease. However, the surface temperature response may be better understood by involving climatic variables in the study.

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The 3D Structure of Atmospheric Blocking: Role of Moisture and Response to Climate Change

10.5194/egusphere-egu21-13585 ◽

2021 ◽

Author(s):

Ebrahim Nabizadeh ◽

Sandro Lubis ◽

Pedram Hassanzadeh

Keyword(s):

Climate Change ◽

Surface Temperature ◽

Northern Hemisphere ◽

Large Scale ◽

3D Structure ◽

Winter Season ◽

Temperature Response ◽

Atmospheric Blocking ◽

Weather Extremes ◽

Large Ensemble

<p>Atmospheric blocking is a large-scale weather phenomenon that interrupts the prevailing eastward progression of pressure systems and can result in weather extremes in the midlatitudes. Due to their devastating consequences, understanding the changes of blocking in response to climate change has been of great interest in recent years. In this study, we investigate the 3D structure of blocking events in reanalysis and two large-ensemble, fully coupled GCM simulations: NCAR&#8217;s CESM1 Large-Ensemble Project (LENS) and GFDL-CM3 large-ensemble project. Here we compare the climatology of blocks in the models with reanalysis and show that the structure of the blocks is remarkably reproduced well in the GCMs, given that these models are known to have biases in reproducing the climatological Northern Hemisphere large-scale circulation. The results of our composite analysis indicate that the blocks exhibit an equivalent-barotropic structure in both summer and winter seasons over both oceans and continents in the northern hemisphere. However, blocking events are stronger in winters compared to summers. We also notice a significant latent heating associated with ascending airstream on the east side of blocks. This warming, which is stronger in winter especially over the ocean basins, leads to a westward shift in the temperature anomaly during blocking episodes. Furthermore, we study the response of the blocks to climate change (RCP8.5) and find that blocking events will be weakened in the summer of three different northern hemisphere regions. However, wintertime blocks&#8217; responses to climate change are more complex than those in summers and depend on the regions and atmospheric pressure levels. Finally, we examined the response of surface temperature associated with blocking events. We have found that the surface temperature response associated with blocking events will be weaker over all the regions in the winter season. However, during summer, the temperature responses will be slightly stronger over Russia and partially over the two ocean basins. Our results suggest that summertime blocking events over Russia are going to be more impactful compared to those over the ocean basins.</p>

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TEMPERATURA DE SUPERFÍCIE E A RELAÇÃO COM O ÍNDICE DE VEGETAÇÃO POR DIFERENÇA NORMALIZADA (NDVI) NA MICROBACIA DO RIO DA BATATEIRAS, CRATO-CE

Revista da Casa da Geografia de Sobral (RCGS) ◽

10.35701/rcgs.v21n2.548 ◽

2019 ◽

Vol 21 (2) ◽

pp. 1310-1320

Author(s):

Cícera Celiane Januário da Silva ◽

Vinicius Ferreira Luna ◽

Joyce Ferreira Gomes ◽

Juliana Maria Oliveira Silva

Keyword(s):

Remote Sensing ◽

Surface Temperature ◽

Temperature Measurement ◽

Rainy Season ◽

Satellite Images ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Landsat 8 ◽

Low Density ◽

Difference Map

O objetivo do presente trabalho é fazer uma comparação entre a temperatura de superfície e o Índice de Vegetação por Diferença Normalizada (NDVI) na microbacia do rio da Batateiras/Crato-CE em dois períodos do ano de 2017, um chuvoso (abril) e um seco (setembro) como também analisar o mapa de diferença de temperatura nesses dois referidos períodos. Foram utilizadas imagens de satélite LANDSAT 8 (banda 10) para mensuração de temperatura e a banda 4 e 5 para geração do NDVI. As análises demonstram que no mês de abril a temperatura da superfície variou aproximadamente entre 23.2ºC e 31.06ºC, enquanto no mês correspondente a setembro, os valores variaram de 25°C e 40.5°C, sendo que as maiores temperaturas foram encontradas em locais com baixa densidade de vegetação, de acordo com a carta de NDVI desses dois meses. A maior diferença de temperatura desses dois meses foi de 14.2°C indicando que ocorre um aumento da temperatura proporcionado pelo período que corresponde a um dos mais secos da região, diferentemente de abril que está no período de chuvas e tem uma maior umidade, presença de vegetação e corpos d’água que amenizam a temperatura.Palavras-chave: Sensoriamento Remoto; Vegetação; Microbacia. ABSTRACTThe objective of the present work is to compare the surface temperature and the Normalized Difference Vegetation Index (NDVI) in the Batateiras / Crato-CE river basin in two periods of 2017, one rainy (April) and one (September) and to analyze the temperature difference map in these two periods. LANDSAT 8 (band 10) satellite images were used for temperature measurement and band 4 and 5 for NDVI generation. The analyzes show that in April the surface temperature varied approximately between 23.2ºC and 31.06ºC, while in the month corresponding to September, the values ranged from 25ºC and 40.5ºC, and the highest temperatures were found in locations with low density of vegetation, according to the NDVI letter of these two months. The highest difference in temperature for these two months was 14.2 ° C, indicating that there is an increase in temperature provided by the period that corresponds to one of the driest in the region, unlike April that is in the rainy season and has a higher humidity, presence of vegetation and water bodies that soften the temperature.Key-words: Remote sensing; Vegetation; Microbasin.RESUMENEl objetivo del presente trabajo es hacer una comparación entre la temperatura de la superficie y el Índice de Vegetación de Diferencia Normalizada (NDVI) en la cuenca Batateiras / Crato-CE en dos períodos de 2017, uno lluvioso (abril) y uno (Septiembre), así como analizar el mapa de diferencia de temperatura en estos dos períodos. Las imágenes de satélite LANDSAT 8 (banda 10) se utilizaron para la medición de temperatura y las bandas 4 y 5 para la generación de NDVI. Los análisis muestran que en abril la temperatura de la superficie varió aproximadamente entre 23.2ºC y 31.06ºC, mientras que en el mes correspondiente a septiembre, los valores oscilaron entre 25 ° C y 40.5 ° C, y las temperaturas más altas se encontraron en lugares con baja densidad de vegetación, según el gráfico NDVI de estos dos meses. La mayor diferencia de temperatura de estos dos meses fue de 14.2 ° C, lo que indica que hay un aumento en la temperatura proporcionada por el período que corresponde a uno de los más secos de la región, a diferencia de abril que está en la temporada de lluvias y tiene una mayor humedad, presencia de vegetación y cuerpos de agua que suavizan la temperatura.Palabras clave: Detección remota; vegetación; Cuenca.

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Do the Heterogeneous Determinants of Repayment Affect Differently across Borrowers of Diverse Credit Sources in Rural Assam? A Double Hurdle Approach

Journal of Development Policy and Practice ◽

10.1177/24551333211031667 ◽

2021 ◽

pp. 245513332110316

Author(s):

Tiken Das ◽

Pradyut Guha ◽

Diganta Das

Keyword(s):

Rural Areas ◽

Probit Model ◽

Original Data ◽

Community Based ◽

Data Set ◽

Brahmaputra Valley ◽

Double Hurdle ◽

Instrumental Variable Probit ◽

Instrumental Variable Probit Model

This study made an attempt to answer the question: Do the heterogeneous determinants of repayment affect the borrowers of diverse credit sources differently? The study is based on data collected from 240 households from three districts in the lower Brahmaputra valley of Assam through a carefully designed primary survey. Besides, the study uses the double hurdle approach and the instrumental variable probit model to reduce possible selection bias. It observes better repayment performance among formal borrowers, followed by semiformal borrowers, while occupation wise it is prominent among organised employees. It has been found that in general, the household characteristics, loan characteristics and location-specific characteristics significantly affect repayment performance of borrowers. However, the nature of impact of the factors influencing repayment performance is remarkably different across credit sources. It ignores the role of traditional community-based organisations in rural Assam while analysing the determinants of repayment performance. The study also recommends for ensuring productive opportunities and efficient market linkages in rural areas of Assam. The study is based on an original data set that has specially been collected to examine question that—do the heterogeneous determinants of repayment affect the borrowers of diverse credit sources differently in the lower Brahmaputra valley of Assam—which has not been studied before.

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Actualized inventory of medicinal plants used in traditional medicine in Oaxaca, Mexico

Journal of Ethnobiology and Ethnomedicine ◽

10.1186/s13002-020-00431-y ◽

2021 ◽

Vol 17 (1) ◽

Author(s):

Cruz-Pérez Alejandra Lucía ◽

Barrera-Ramos Jacqueline ◽

Bernal-Ramírez Luis Alberto ◽

Bravo-Avilez David ◽

Rendón-Aguilar Beatriz

Keyword(s):

Rural Communities ◽

Medicinal Plants ◽

Ethnic Groups ◽

Traditional Knowledge ◽

Original Data ◽

Risk Category ◽

Important Species ◽

Points Of View ◽

Almost All

Abstract Background Oaxaca is one of the most diverse states in Mexico from biological and cultural points of view. Different ethnic groups living there maintain deep and ancestral traditional knowledge of medicinal plants as well as traditional practices and beliefs about diseases/illnesses and cures. Previous ethnobotanical research in this state has helped document this knowledge, but with the addition of more studies, more records appear. We updated the inventory of medicinal knowledge between the different ethnic groups that inhabit the Oaxacan territory. Methods A database was constructed from two sources: (1) original data from a 3-year project in 84 municipalities of Oaxaca inhabited by eight ethnic groups and (2) different electronic databases. Results Records of 1032 medicinal plants were obtained; 164 families were registered, with Asteraceae, Fabaceae, and Rubiaceae being the most commonly used. A total of 770 species were reported in 14 vegetation types; the most important species came from temperate forests. Only 144 species corresponded to introduced species, and 272 were listed in a risk category. Illnesses of the digestive and genitourinary systems as well as culture-bound syndromes were treated with high numbers of medicinal plants. The Mestizo, Mixe, Mixtec, and Zapotec ethnic groups exhibited the greatest number of recorded medicinal plants. The 17 species that were used among almost all ethnic groups in Oaxaca were also used to cure the highest number of diseases. Discussion Inventories of medicinal plants confirm the persistence of traditional knowledge and reflect the need to recognize and respect this cosmovision. Many species are gathered in wild environments. The most important illnesses or diseases recorded in the present inventory are also mentioned in different studies, suggesting that they are common health problems in the rural communities of Mexico. Conclusions Medicinal plants are essential for ethnic groups in Oaxaca. It is necessary to recognize and understand the complex ancestral processes involved in the human-nature interaction and the role of these processes in the conservation of biodiversity and in the survivorship of ethnic groups that have persisted for centuries. Finally, this study serves as a wake-up call to respect those worldviews.

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The relevance of mid-Holocene Arctic warming to the future

Climate of the Past ◽

10.5194/cp-15-1375-2019 ◽

2019 ◽

Vol 15 (4) ◽

pp. 1375-1394 ◽

Cited By ~ 6

Author(s):

Masakazu Yoshimori ◽

Marina Suzuki

Keyword(s):

Surface Temperature ◽

General Circulation ◽

Temperature Response ◽

Longwave Radiation ◽

General Circulation Models ◽

Cross Model ◽

Arctic Warming ◽

Temperature Changes ◽

The Future ◽

Arctic Climate Change

Abstract. There remain substantial uncertainties in future projections of Arctic climate change. There is a potential to constrain these uncertainties using a combination of paleoclimate simulations and proxy data, but such a constraint must be accompanied by physical understanding on the connection between past and future simulations. Here, we examine the relevance of an Arctic warming mechanism in the mid-Holocene (MH) to the future with emphasis on process understanding. We conducted a surface energy balance analysis on 10 atmosphere and ocean general circulation models under the MH and future Representative Concentration Pathway (RCP) 4.5 scenario forcings. It is found that many of the dominant processes that amplify Arctic warming over the ocean from late autumn to early winter are common between the two periods, despite the difference in the source of the forcing (insolation vs. greenhouse gases). The positive albedo feedback in summer results in an increase in oceanic heat release in the colder season when the atmospheric stratification is strong, and an increased greenhouse effect from clouds helps amplify the warming during the season with small insolation. The seasonal progress was elucidated by the decomposition of the factors associated with sea surface temperature, ice concentration, and ice surface temperature changes. We also quantified the contribution of individual components to the inter-model variance in the surface temperature changes. The downward clear-sky longwave radiation is one of major contributors to the model spread throughout the year. Other controlling terms for the model spread vary with the season, but they are similar between the MH and the future in each season. This result suggests that the MH Arctic change may not be analogous to the future in some seasons when the temperature response differs, but it is still useful to constrain the model spread in the future Arctic projection. The cross-model correlation suggests that the feedbacks in preceding seasons should not be overlooked when determining constraints, particularly summer sea ice cover for the constraint of autumn–winter surface temperature response.

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Role of sea surface temperature responses in simulation of the climatic effect of mineral dust aerosol

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-6049-2011 ◽

2011 ◽

Vol 11 (12) ◽

pp. 6049-6062 ◽

Cited By ~ 30

Author(s):

X. Yue ◽

H. Liao ◽

H. J. Wang ◽

S. L. Li ◽

J. P. Tang

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

Radiative Forcing ◽

Mineral Dust ◽

Dust Aerosol ◽

Sea Surface ◽

Climatic Effect ◽

Radiative Effects ◽

Climate Simulations

Abstract. Mineral dust aerosol can be transported over the nearby oceans and influence the energy balance at the sea surface. The role of dust-induced sea surface temperature (SST) responses in simulations of the climatic effect of dust is examined by using a general circulation model with online simulation of mineral dust and a coupled mixed-layer ocean model. Both the longwave and shortwave radiative effects of mineral dust aerosol are considered in climate simulations. The SST responses are found to be very influential on simulated dust-induced climate change, especially when climate simulations consider the two-way dust-climate coupling to account for the feedbacks. With prescribed SSTs and dust concentrations, we obtain an increase of 0.02 K in the global and annual mean surface air temperature (SAT) in response to dust radiative effects. In contrast, when SSTs are allowed to respond to radiative forcing of dust in the presence of the dust cycle-climate interactions, we obtain a global and annual mean cooling of 0.09 K in SAT by dust. The extra cooling simulated with the SST responses can be attributed to the following two factors: (1) The negative net (shortwave plus longwave) radiative forcing of dust at the surface reduces SST, which decreases latent heat fluxes and upward transport of water vapor, resulting in less warming in the atmosphere; (2) The positive feedback between SST responses and dust cycle. The dust-induced reductions in SST lead to reductions in precipitation (or wet deposition of dust) and hence increase the global burden of small dust particles. These small particles have strong scattering effects, which enhance the dust cooling at the surface and further reduce SSTs.

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A comparative study of Pleurosigma subrectum and P. acus (Bacillariophyta)

Phytotaxa ◽

10.11646/phytotaxa.207.3.5 ◽

2015 ◽

Vol 207 (3) ◽

pp. 273

Author(s):

FRITHJOF A.S. STERRENBURG ◽

STUART R. STIDOLPH ◽

EUGENIA A. SAR ◽

Ines Sunesen

Keyword(s):

Comparative Study ◽

Original Data ◽

Type Material ◽

Diatom Species ◽

Morphological Differences ◽

Sem Investigation ◽

Made In

In continuation of an earlier paper on Pleurosigma species with an (almost) non-sigmoid valve and raphe sternum, a comparative study was made in LM and SEM of Pleurosigma subrectum and P. acus. For P. subrectum, slides and a subsample of the type material were examined. For P. acus no unmounted material permitting SEM investigation is extant; a sample containing specimens fully matching the type in LM was therefore used as epitype material for SEM. The original data on striation of P. acus are emended. No morphological differences indicating separate specific status of these two taxa were observed and P. acus is therefore here designated a heterotypic synonym of P. subrectum. From the data now available, this is a very widely distributed species. The study demonstrates the indispensable role of collections for investigations on the diversity and distribution of diatom species.

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