Publicações

We use an unprecedented ensemble of regional climate model (RCM) projections over seven regional CORDEX domains to provide, for the first time, an RCM-based global view of monsoon changes at various levels of increased greenhouse gas (GHG) forcing. All regional simulations are conducted using RegCM4 at a 25 km horizontal grid spacing using lateral and lower boundary forcing from three General Circulation Models (GCMs), which are part of the fifth phase of the Coupled Model Inter-comparison Project (CMIP5). Each simulation covers the period from 1970 through 2100 under two Representative Concentration Pathways (RCP2.6 and RCP8.5). Regional climate simulations exhibit high fidelity in capturing key characteristics of precipitation and atmospheric dynamics across monsoon regions in the historical period. In the future period, regional monsoons exhibit a spatially robust delay in the monsoon onset, an increase in seasonality, and a reduction in the rainy season length at higher levels of radiative forcing. All regions with substantial delays in the monsoon onset exhibit a decrease in pre-monsoon precipitation, indicating a strong connection between pre-monsoon drying and a shift in the monsoon onset. The weakening of latent heat driven atmospheric warming during the pre-monsoon period delays the overturning of atmospheric subsidence in the monsoon regions, which defers their transitioning into deep convective states. Monsoon changes under the RCP2.6 scenario are mostly within the baseline variability. 

The marine reservoir of dissolved organic carbon (DOC) is equivalent to the atmospheric carbon reservoir and represents the largest reduced carbon stock in the ocean. However, the role of DOC in the global carbon cycle is not fully understood. In this study, we analyzed the distribution of DOC in the water column of the Bransfield Strait, Northern Antarctic Peninsula. Data were collected during two summer cruises of the NAUTILUS project conducted by the Brazilian High Latitude Oceanography Group in February 2015 and 2016. We investigated the possible effects of the El Nino – Southern Oscillation (ENSO) and Southern Annular Mode (SAM) climate modes on DOC variability based on correlations between DOC and temperature, salinity, and dissolved oxygen. Concentrations of DOC ranged from 40.70 to 122.82 mu mol kg(-1) in 2015 and 33.12 to 112.20 mu mol kg(-1) in 2016. The analysis shows that the vertical distribution of DOC in the Bransfield Strait may be controlled by a combination of vertical stratification, vertical export of organic matter and biological activity in the upper mixed layer during summertime. The significant interannual differences observed between DOC concentration and most physicochemical parameters may be linked to ENSO and SAM climate modes. The highest DOC concentration was observed in February 2015, associated with a layer of warm surface water, due to the higher stratification of the water column. The ENSO and SAM climate modes were low and positive in that year, favoring intrusions of waters from the Antarctic Circumpolar Current. In contrast, February 2016 was characterized by record positive ENSO and SAM modes. The intensification of the Weddell Gyre induced the advection of cold, more oxygenated and recently formed shelf waters into the Bransfield Strait, which may have contributed to the lower DOC concentrations. This study contributes to a better understanding of the role of DOC in the global carbon cycle in a region of complex ocean circulation and mixing, and sensitive to global climate change.

Land surface/ecosystem models (LSEMs) play a key role in understanding the Earths climate. They represent ecosystem dynamics by simulating fluxes occurring between the biosphere and atmosphere. However, for a correct flux simulation, it is critical to calibrate the model using robust and state-of-the-art calibration techniques. In this work, we optimize parameters of the Integrated Model of Land Surface Processes (INLAND) using the hierarchical multi-objective calibration method (AMALGAM) to improve the representation of surface processes in a natural ecosystem over the Pampa biome in South America. The calibration was performed using experimental data of energy and CO2 flux collected in a native field located in southern Brazil. We compared simulations using the default and calibrated parameter set. The results show that the calibration of the model significantly improved all fluxes analyzed. The mean errors and bias values were significantly reduced, and the seasonality of fluxes was better represented. This work is one of the first to apply a multi-objective calibration in an LSEM to represent surface fluxes in the Pampa biome, presenting a consistent set of parameters for future applications used in studies of biome land use and land cover.

This study is concerned with the effects of a decrease in the air pollution concentration on the lightning characteristics of two large Brazilian cities. The decrease in air pollution happened from March 20, till April 02, 2020, and it was caused by the social distancing effort to contain the COVID-19 spread in the cities. In Sao Paulo, the ratio between cloud-to-ground to intracloud flashes and the average peak current of negative cloud-to-ground flashes significantly decreased; whereas in Belo Horizonte, the ratio between positive and negative cloud-toground flashes significantly increased with respect to the values in previous years.

Eutrophication is the prime water quality issue in inland waters. Eutrophication and its key symptom, harmful cyanobacterial blooms, is expected to further increase in the future, which highlights the importance of managing the issue. The reduction of external nutrient load is crucial but might not bring fast relief to eutrophic waters due to ongoing diffuse pollution and legacy nutrients in the sediment. In this context, in-lake measures are needed to speed-up recovery. In this review, we discuss different in-lake measures based on coagulation and precipitation of cyanobacteria and/or phosphate for different lake categories (e.g., shallow or deep, mainly external or internal nutrient load, occurrence of perennial or summer blooms). In deep lakes with an external nutrient load higher than the internal load, a Floc and Sink method could be used in which a coagulant (e.g. aluminium salts, Al-salts; chitosan) combined with a ballast (e.g. soil, clay) removes a cyanobacterial bloom out of the water column. In case the deep lake suffers from high internal load, a phosphate (P)-fixative (e.g. lanthanum modified bentonite or Al-salts) can be used to Lock the legacy P, possibly combined with a coagulant a Floc and Lock technique. The latter approach will target both the particulate P in a bloom and the internal P load. A shallow lake that suffers from summer blooms and in which the internal load is higher than the external load, a Lock strategy of winter application of a P-fixative is proposed to prevent bloom development. In shallow lakes with perennial blooms, an agent to damage the cells (such as H2O2) is required together with a coagulant and a ballast to avoid recolonization of the water column due to resuspension a Kill, Floc and Sink/ Lock method. The selection of the most promising in-lake measures and materials should be based on a proper system diagnosis and tests prior to a full-scale intervention. These methods can be effective, but evidently reduction of external nutrient loads, both from point- and non-pointed sources, is an absolute necessity to restore aquatic ecosystems in a holistic sense.

Digital cameras deployed on the surface are frequently used for monitoring atmospheric conditions. Several methods were developed to use the images for synoptic observations, cloud assessments, validation of satellite models, short term forecasting and so on. However, there are some restrictions not considered by these methods, especially when a linear camera sensor is used to observe logarithmic ranges of atmospheric luminance. Cameras usually accommodate the scene to a linear scale causing distortions on pattern distributions by pixel value saturation (PVS) and drifts from its original hues. This solution brings on some simplifying practices commonly found in the literature to overcome these problems. But those practices result in loss of data, misinterpretation of valid pixels and restriction on the use of computer vision algorithms. The present work begins by illustrating these problems performing supervised learning and analysis for two reasons: all observation systems seek out automation of human synoptic observation in order to provide a sound mathematical modeling of the observed patterns. A new modeling paradigm is proposed to map the sky patterns to represent the existent physical atmospheric phenomena not considered by the approaches found over the literature. In order to validate the proposed method, we compared the results of the analysis of 1630 images against two well-established methods. A hypothesis test showed that results are compatible with currently used dichotomizer approach with advantages, although the proposed method was downgraded to a common comparison ground. Differences were due to PVS and as well as other restrictions not considered by the methods existent on literature. Finally, the present work concludes that the new paradigm presents more meaningful results of sky patterns interpretation, allowing extended daylight observation periods and uses a higher dimensional domain of color space available for the analysis.

The United Nations 2030 Agenda catalysed the development of global target-seeking sustainability-oriented scenarios representing alternative pathways to reach the Sustainable Development Goals (SDGs). Implementing the SDGs requires connected actions across local, national, regional, and global levels; thus, target-seeking scenarios need to reflect alternative options and tensions across those scales. We argue that the design of global sustainability-oriented target-seeking scenarios requires a consistent process for capturing multiple and contrasting perspectives on how to reach the goals, including the perspectives from multiple scales (e.g. local, national, regional) and geographic regions (e.g. the Global South). Here we propose a novel approach to codesign global target-seeking scenarios, consisting of (a) capturing global perspectives on pathways to the SDGs through a review of existing global scenarios; (b) a multi-stakeholder process to obtain multiple sub-global perspectives on pathways to sustainability; (c) an analysis of convergences, and crucially, divergences between global and regional perspectives on pathways to reach the SDGs, feeding into the design of new target-seeking scenario narratives. As a case study, we use the results of the 2018 African Dialogue on The World in 2050, discussing the future of agriculture and food systems. The identified divergent themes emerging from our analysis included urbanization, population growth, agricultural practices, and the roles of different actors in the future of agriculture. The results challenge some of the existing underlying assumptions of the current sustainability-oriented global scenarios (e.g. population growth, urbanisation, agricultural practices), indicating the relevance and timeliness of the proposed approach. We suggest that similar approaches can be replicated in other contexts to better inform the process of sustainability-oriented scenario co-design across scales, regions and cultures. In addition, we highlight the implications of the approach for scenario quantification and the evolution of modeling tools.

O conhecimento e o desenvolvimento científicos e tecnológicos promovidos por Universidades e Instituições de Pesquisa são essenciais para o Brasil, bem como sua difusão à população, de modo que a sociedade tenha consciência de sua importância e apoie novas produções no âmbito da ciência e da tecnologia. Diante desse contexto, o Projeto Educação Extensão Educacional: Um Projeto de Difusão do Conhecimento Científico foi iniciado em 2017 pelo Centro de Ciência do Sistema Terrestre (CCST) do Instituto Nacional de Pesquisas Espaciais (INPE), com o objetivo de promover ao sistema educacional e à sociedade brasileira palestras sobre temas ambientais inerentes aos trabalhos do Instituto. Assim, esta Iniciação Científica teve como objetivo principal contribuir para o avanço do Projeto por meio de: levantamento dos temas e trabalhos desenvolvidos pelo INPE; pesquisas acadêmicas em bancos de dados científicos sobre os temas a serem difundidos; consultas no banco de dados do Projeto aos temas, número de palestras realizadas e número de participantes alcançados; e análise dos dados. Desde o início de sua atuação, em 2017, o Projeto promoveu um total de 289 palestras didáticas relacionadas aos seguintes temas científico ambientais: Biomas do Brasil; Desastres Naturais e Escorregamentos de Terra; Desmatamento; Difusão do Conhecimento Científico; Eucalipto; Fitorremediação; Geografia da Malária no Brasil; Geotecnologias; Hidrologia e Mudanças do Uso e Cobertura da Terra; Meteorologia Básica; Mudanças Ambientais Globais; Oceanografia; Padrões de Urbanização e Gestão das Cidades; Pegada Ecológica; Qualidade do Ar; Queimadas; Recuperação de Nascentes; e Reflorestamento. Essas informações, bem como outros dados relevantes ao Projeto, são armazenadas e constantemente atualizadas em um banco de dados criado em 2018. A qualidade das palestras foi avaliada em 2019 através de pesquisa eletrônica realizada com os participantes, cujos resultados foram positivos. Dentre os temas citados, o mais abordado tanto em 2017 quanto em 2019 foi Biomas do Brasil. Em 2018, predominaram as palestras sobre Desastres Naturais e Escorregamentos de Terra. Os temas Desmatamento, Qualidade do Ar, Queimadas, Recuperação de Nascentes e Reflorestamento foram frequentemente difundidos durante todos os anos do Projeto. Ademais, em 2019, foram promovidos os cursos: Uso de geotecnologias em estudos ambientais, realizado na Escola de Engenharia de Lorena (EEL/USP); e Técnicas de preservação e recuperação ambiental: um projeto de revitalização do espaço escolar, na Escola Estadual Maria Izabel Fontoura, localizada no município de Cachoeira Paulista. Através dessas ações, foi alcançado um total de 11.399 pessoas, incluindo Alunos (Discentes) e Professores (Docentes) dos ensinos fundamental e médio de escolas públicas e de Universidades. Estão em desenvolvimento novos temas, como Biorremediação de solos contaminados, a serem palestrados no futuro com a sequência do Projeto.

The United Nations 2030 Agenda catalysed the development of global target-seeking sustainability-oriented scenarios representing alternative pathways to reach the Sustainable Development Goals (SDGs). Implementing the SDGs requires connected actions across local, national, regional, and global levels; thus, target-seeking scenarios need to reflect alternative options and tensions across those scales. We argue that the design of global sustainability-oriented target-seeking scenarios requires a consistent process for capturing multiple and contrasting perspectives on how to reach the goals, including the perspectives from multiple scales (e.g. local, national, regional) and geographic regions (e.g. the Global South). Here we propose a novel approach to codesign global target-seeking scenarios, consisting of (a) capturing global perspectives on pathways to the SDGs through a review of existing global scenarios; (b) a multi-stakeholder process to obtain multiple sub-global perspectives on pathways to sustainability; (c) an analysis of convergences, and crucially, divergences between global and regional perspectives on pathways to reach the SDGs, feeding into the design of new target-seeking scenario narratives. As a case study, we use the results of the 2018 African Dialogue on The World in 2050, discussing the future of agriculture and food systems. The identified divergent themes emerging from our analysis included urbanization, population growth, agricultural practices, and the roles of different actors in the future of agriculture. The results challenge some of the existing underlying assumptions of the current sustainability-oriented global scenarios (e.g. population growth, urbanisation, agricultural practices), indicating the relevance and timeliness of the proposed approach. We suggest that similar approaches can be replicated in other contexts to better inform the process of sustainability-oriented scenario co-design across scales, regions and cultures. In addition, we highlight the implications of the approach for scenario quantification and the evolution of modeling tools.

Um dos maiores desafios para a sociedade nesse século é o de minimizar os impactos do sistema alimentar sobre o ambiente. Este trabalho estima a área para produção de alimentos no Brasil e avalia se a produção agrícola nacional seria suficiente para promover a segurança alimentar limitando a expansão da agricultura, bem como explora os impactos de diferentes dietas para o uso da terra. Mais especificamente, foram combinadas oferta e demanda de alimentos, em termos de nutrientes fornecidos ao sistema alimentar nacional, baseado em três décadas de dados sobre produção agrícola, comércio internacional, uso da terra e população. Assim, as tendências de disponibilidades de nutrientes ao sistema alimentar foram avaliadas em conjunto com as projeções de crescimento populacional em cenários de mudanças de dietas com limitação de uso da terra. Os resultados indicam que, nas últimas três décadas, o Brasil utiliza em média 22% de sua área agrícola para a produção de alimentos, e que nenhuma expansão da agropecuária é necessária no futuro para promoção da segurança alimentar e nutricional. Ainda, em cenários com menores níveis de produção e consumo produtos de origem animal, entre 50% e 90% menos terra seriam necessárias para a produção de alimentos em quantidades suficientes. Conclui-se que o sistema alimentar brasileiro poderia promover a segurança alimentar sem mais expansão da agricultura ou mudança de dieta e que dietas com menores níveis de consumo de carne reduziriam substancialmente a demanda de terra para alimentar a população. Assim, são fornecidas evidências de que a produção de alimentos é compatível com a conservação ambiental no Brasil.