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Browsing by Author "Henriques, Diamantino"

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  • Aerosol Optical Depth measurements in the Azores.
    Publication . Carvalho, Fernanda; Henriques, Diamantino; Fialho, Paulo
    A preliminary analysis of AOD results from sun-photometer measurements collected at Jose Agostinho Observatory at Angra do Heroísmo (Terceira Island, the Azores) was presented. The observational period ranges from August 2004 to December 2007, using a SP02 sun-photometer at wavelengths 412, 500, 675, and 862 nm, coupled to a 2AXP sun-tracker. The sampling interval is 5 s and data is filtered for cloud contamination in a time window of 10 minutes. Most AOD 500 nm values are below 0.3, showing a small variation during the day; frequency distribution shows a typical right skew distribution. Alpha and beta Angstrom coefficients were also computed and analyzed in the same way. Alpha values are generally positive and lower than 4, while beta values are below 1.5. AOD results from the AERONET station at Horta Observatory (Faial Island, the Azores) were also used and compared with Angra data. AOD and Angstrom coefficients were also analyzed with wind results from the automatic weather station located at both observatories. Results show different wind distributions due to different exposures; however, systematic higher AOD values are found at Horta. The proximity of the two sites indicates that these differences are more likely due to different instruments and processing methods used.
    2008-07Conference object Open access Show more
  • An approach to evaluate aerosol optical depth at marine boundary layer : the Pico-Graciosa measurement platform
    Publication . Henriques, Diamantino; Carvalho, Fernanda; Fialho, Paulo
    Aerosols are an important constituent of the atmospheric boundary layer. Aerosol particles provide surfaces for heterogeneous chemical processes, they also act as a condensation sink for atmospheric trace species. In the marineatmosphere originate from a variety of production and transformation processes that includes sea spray aerosol produced at the sea surface through the interactions between wind and surface waves (Liss and Johnson, 2013).
    2015Conference object Open access Show more
  • Complexo CLIMAAT-TERCEIRA-NARE para a monitorização da composição da atmosfera na camada limite do Atlântico Norte
    Publication . Fialho, Paulo; Henriques, Diamantino; Carvalho, Fernanda; Barata, Filipe; Azevedo, Eduardo B.
    As a result of the partnership between the University of Azores, and the Association for the Study of the Insular Environment through the Environment Observatory and the Meteorological Institute, during the 2004 summer it took place the beginning of the installation of the CLIMAAT – TERCEIRA – NARE (INTERREG IIIB – Projecto CLIMAAT – MAC 2.3/A3) platform. In this stage, it was also installed in the José Agostinho observatory, near the city of Angra do Heroísmo, several equipments to monitoring the atmospheric and sun irradiation. Near the coast, at the moment, and beside the meteorological common parameters, pressure, temperature, relative humidity, precipitation, wind direction and intensity some measurements of the black carbon and iron oxide aerosol absorption coefficients were also done. The results of this project should contribute to the study of the evolution and composition of the North Atlantic atmosphere, and in that matter to the study of the Global Changes, namely as a land platform of reference to remote sensing satellite systems. This platform is part of the Azores Global Atmosphere Monitoring Complex (AGAMC).
    2005Report Open access Show more
  • Evaluation of Solar Energy Potential and its Variability in the Azores.
    Publication . Carvalho, Fernanda; Henriques, Diamantino; Fialho, Paulo; Vieira, Elsa; Santos, Jorge
    2010-06Conference object Open access Show more
  • Monitorização do Carbono Negro no Arquipélago dos Açores
    Publication . Barata, Filipe; Fialho, Paulo; Pio, Casimiro; Afonso, Joana; Oliveira, Tiago S.; Henriques, Diamantino; Carvalho, Fernanda
    A presence do aerosol Carbono Negro tem sido analisada em dois locais do Arquipélago dos Açores. Um pretende reflectir as condições na troposfera livre da região do Atlântico Norte (PICO-NARE – 38.471º N, 27.404º W, 2225m de altitude), o outro as condições de fronteira maritime na mesma região (CLIMAAT-TERCEIRA-NARE – 38.691º N, 27.354º W, 50 m de altitude) (INTERREG IIIB – Projecto CLIMAAT-MAC 2.3/A3). No PICO-NARE utilizou-se um Etalómetro em amostragem continua (usualmente amostragem no período de 24 horas) e análise, em intervalos de 5 minutos, do equivalente de concentração de massa de Carbono Negro. No CLIMAAT-TERCEIRA-NARE instalou-se um Etalómetro nas mesmas condições e também um Colector de Partículas de Grande Caudal para amostragem de aerossóis em períodos contínuos de 7 dias, amostras que posteriormente foram enviadas para análise da concentração de massa de Carbono Negro por técnica Termo-Óptica, na Universidade de Aveiro. Os resultados médios obtidos, para o período de Julho de 2001 a Janeiro de 2004, de equivalents de concentração de massa de Carbono Negro, foram de: 85.85 ± 33.83 ng/m³ (max: 201.20 ng/m³, min: 41.57 ng/m³) para CLIMAAT-TERCEIRA-NARE e 37.48 ± 18.99 ng/m³ (max: 84.94 ng/m³, min: 12.65 ng/m³) para PICO-NARE. Para a concentração de massa de carbono negro, no CLIMAAT-TERCEIRA-NARE, obteve-se a media mensal de 49.01 ± 27.77 ng/m³ (max: 130.75 ng/m³, min: 1.55 ng/m³).
    2005Report Open access Show more
  • Mudança Climática e Impacte nas Energias Renováveis nos Açores: Visões estratégicas para a sustentabilidade
    Publication . Carvalho, Fernanda; Henriques, Diamantino; Meirelles, Maria Gabriela; Vasconcelos, Helena Cristina; Porteiro, João; Navarro, Patrícia
    O Clima da Terra é o resultado de um enorme conjunto de interações não lineares entre vários subsistemas do Sistema Climático. O termo Alterações Climáticas (AC) tem sido adotado como uma mudança do clima devida a causas naturais ou antropogénicas. O setor da energia é o maior contribuinte para as emissões de gases com efeito de estufa à escala global, mas poderá também ser seriamente afetado devido à mudança climática. Neste trabalho, utilizam-se as projeções climáticas baseadas num conjunto de modelos numéricos de circulação global, para simular o clima até ao final do século e tendo presente os cenários alternativos de emissões poluentes. Na Região Autónoma dos Açores (RAA), apesar dos esforços na implementação de energias renováveis, a dependência dos combustíveis fósseis para a produção de energia continua a ser elevada. […].
    2022-09-18Periodical Open access Show more
  • Observações da Espessura Óptica dos Aerossóis nos Açores
    Publication . Carvalho, Fernanda; Henriques, Diamantino; Fialho, Paulo; Bettencourt, Vera
    First results of aerosol optical depth measurements out with a Middleton SP02 sun photometer mounted on a sun tracker system (Kipp & Zonen 2AP) in Terceira Is. (Azores) are presented. SP01 and Cimel data from AERONET programme at Faial Is. are compared and analyzed with respect to weather conditions. These measurements are a part of the Portuguese Meteorological contribution for the development of a Global Station in the scope of the GAW/WMO programme in close cooperation with Azores University. The installation and operation of these instruments are partially funded by CLIMAAT (INTERREG IIIB – Project CLIMAAT – MAC 2.3/A3). Ground based measurements collected at Terceira Is. should be useful on long term referencing and assessing of the performance of space-borne instruments over North Atlantic Region.
    2005Report Open access Show more
  • Observações da quantidade total de ozono e da radiação de UV nos Açores
    Publication . Henriques, Diamantino; Carvalho, Fernanda; Fialho, Paulo
    First results of total ozone and ultraviolet radiation measurements carried out with a Brewer Spectrophotometer MKII in Terceira Is. (Azores) are presented. A brief description of the Brewer Spectrophotometerand and total ozone and sulphur dioxide retrieval method is done. Six months of Brewer and TOMS total ozone data are compared and analysed as well as UV changes during a selected period. These measurements are a part of the Portuguese Meteorological contribution for the development of a Global Station in the scope of the GAW/WMO programme in close cooperation with Azores University. The installation and operation of this instrument are partially funded by ROCA II (FCT) and CIMAAT (INTERREG IIIB – Project CLIMAAT – MAC 2.3/A3) projects. Ground based measurements collected at Terceira Is. should be useful on long term referencing and assessing of the performance of space-borne instruments over North Atlantic Region.
    2005Report Open access Show more
  • Projeções Climáticas para os Açores: Avaliação da Temperatura do Ar sob Diferentes Cenários Socioeconómicos (SSP)
    Publication . Henriques, Diamantino; Carvalho, Fernanda; Meirelles, Gabriela; Vasconcelos, Helena
    Em pequenas regiões insulares, a influência das mudanças climáticas assume uma relevância particular. No arquipélago dos Açores, composto por nove ilhas, as circunstâncias geográficas, a condição oceânica, a dispersão territorial, o modelo de uso da terra e outras restrições impostas pelas características físicas da região, como relevo, clima e hidrografia reforçam e aumentam a vulnerabilidade das ilhas a mudanças nos padrões climáticos atuais.
    2024-09-01Journal article Open access Show more
  • UV Index estimation from global radiation and total column ozone.
    Publication . Fialho, Paulo; Henriques, Diamantino; Carvalho, Fernanda
    2008-05Lecture Open access Show more