PARTNERSHIP WITH THE OXFORD UNIVERSITY – THE SUMMER INTERNSHIP PROGRAM



Oxford University students in 2019:

Hayley firth
Period: 07/03/2019 to 08/09/2019
Research Area: Modeling and Studies of Renewable Energy Resources
Paper Title: Investigation on the cloud edge effect in Brasilia and Petrolina
Supervisors: Enio Bueno Pereira, Madeleine Sánchez Gácita Casagrande, Francisco José Lopes de Lima and Eduardo dos Santos Pereira

Abstract: How can clouds extend the radiation reaching the Earth’s surface, the ways in which it can occur, and the different limits to categorize this phenomenon. Many interesting patterns seen in the January Brasilia and February Petrolina datasets, which include camera images in the sky.

Louis wood
Period: 07/10/2019 to 08/09/2019
Research Area: Biosphere-Atmosphere Interaction
Paper Title: Understanding the Cerrado region of Brazil and its projected changes
Supervisor: Manoel Ferreira Cardoso

Abstract: The biodiversity of the Cerrado region in Brazil regarding climate and land use, as well as its projected changes. First, the relationship between biodiversity in the region and various bioclimatic variables, such as average annual temperature and rainfall seasonality. Given the predicted changes in climate and land use by the year 2050, the areas of high biodiversity to be most affected can be identified. While most studies of this nature examine the effects of these changes on a particular species or genus, this paper will consider the effect on the region as a whole.

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In 2018, the PPG-CST received 5 students from Oxford University for a 4-6 week internship. The following is a summary of the activities performed:

Katherine Heath
Period: 6/15/2018 to 7/31/2018
Research Area: Climate Change Projections & Modeling
Job Title: Response of mosquito population dynamics to climate change in Brazil
Supervisor: Lincoln Muniz Alves

Abstract: Mosquito-borne diseases such as zika, dengue and chikungunya present a huge global health problem. The problem is particularly pronounced in Brazil, where environmental conditions favor the persistence of the Aedes aegypti mosquito, which is a vector of these diseases. Previous studies have modeled the associations between climate and dengue cases. However, we believe it is important to focus on mosquito ecology, not just the occurrence of the disease. This is because we live in a changing world, where urbanization, agricultural expansion and climate change change mosquito habitats. The effects on the main vector of the disease, Aedes aegypti, cannot be captured by focusing only on dengue cases. The aim of this study was to evaluate the influence of climate change on the population dynamics of Aedes aegypti in Brazil. We use the production of the HadGEM2-ES climate model (between 2000 – 2100) forced by the RCP 4.5 and 8.5 scenarios, allowing us to compare and contrast the effects of the future climate on mosquito populations, depending on whether we are pessimistic or optimistic about climate change. We also used occurrence data available from a comprehensive entomological survey in 2013 to create a probability map of Aedes aegypti occurrence in Brazil, which was combined with the output model. Overall, this study found that the population size of Aedes aegypti in Brazil will increase dramatically. In northeastern Brazil, mosquitoes will remain endemic for the next 80 years due to favorable temperature conditions. Southeastern Brazil – including Rio de Janeiro and Sao Paulo – sees the highest degree of seasonality in mosquito occurrence, with higher numbers in the summer months. Mosquitoes can also begin to invade new areas, especially in southern Amazonas. Fundamentally, the presence of Aedes aegypti is directly related to the incidence of the disease. Therefore, the increase in mosquito numbers throughout Brazil as a result of climate change will result in an increase in mosquito-borne diseases. There are many factors that affect the occurrence of mosquitoes, such as urbanization, agricultural expansion and population density, as well as climate. We use a probability map based on available survey data to capture this. Future studies should focus on mechanistic explanations of mosquito occurrence, considering additional environmental factors.

Edward Clennett
Period: 07/02/2018 to 08/11/2018
Research Area: Severe Weather and Lightning
Job Title: Electrostatic field patterns produced by ordinary and severe storms in the region of Campinas
Supervisor: Kleber Pinheiro Naccarato

Abstract: The SOS CHUVA project, which took place between December 2016 and June 2018, included the collection of atmospheric electric field, radar and lightning data in the Campinas region. The Barnes interpolation method was then used to produce electric field maps on a 110 by 115 km grid covering Campinas. Analysis of 9 of the 43 cases, selected for being static storms over Campinas, with lateral extension of similar size or smaller than the area of ​​the sensor network, revealed that, in general, strong negative and positive fields are present below ground level. thunderstorms, the latter often occurring after lightning flashes or at a distance of 10kms from thunderstorms. Irregularities, including the occasional lack of electrification below the storms, and the detection of fields under clear skies or displaced from convective centers, were also observed, challenging our understanding of cloud electrification. To properly investigate these unexpected phenomena, a larger and denser sensor network is required, as well as more interpolation runs using different weighting factors.

Alexander Doran
Period: 07/03/2018 to 08/10/2018
Research Area: Deforastion & Biomass Fires
Job Title: Regional patterns of land cover and biological richness in the Cerrado in Brazil
Supervisor: Manoel Ferreira Cardoso

Abstract: The Cerrado covers approximately 23% of Brazil’s territory and is the largest and richest biologically neotropical Savannah in the world. Approximately 30% of Brazil’s biodiversity is located in the Cerrado, but less than 50% of the Cerrado remains as its natural land use cover. The region is believed to support more than 16,000 species of plants, animals and fungi, where thousands of these plant species are endemic.

In this project we (1) analyze the main distribution of land use within the region, (2) look at the patterns of biological wealth within the biome, and (3) evaluate how these two patterns relate to each other and to biome locations. protected areas within the Cerrado. Land use data from the Mapbiomas 2.3 collection, aggregated in the spatial lattice of 0.5o lat / lon based on the (most common) modal value within each grid cell, were used. For biological richness data, we extracted biological observations from Reino Plantae from the Global Biodiversity Information Facility (GBIF), which provided us with a data set containing 490045 records, after removing duplicates and information that were not identified for the species level. These data were aligned with land use data, allowing us to calculate the richness of species, genera and families within each grid square of 0.5 to 0.50 degrees. Protected area polygons are from the Chico Mendes Institute for Biodiversity Conservation (ICMBio). As a result of our analysis, we see extremely high species richness in certain areas of the Cerrado, with higher values ​​located in the SE and central portions of the biome and often overlapping human land areas. Two of the biggest contributors to change in land use have been the replacement of natural vegetation by exotic grasses with pastures and eucalyptus plantations by wood and charcoal. These will typically have less biodiversity than native vegetation. The 2010 agricultural frontier in the states of Maranhão, Tocantins, Piaui and Bahia (MaToPiBa) will have increased pressure on the North, where another important and biodiverse region may be lost to agriculture. The vast majority of protected areas align with the natural land use areas. This implies that they succeeded in limiting deforestation. However, it is interesting to see that only 50-65% of protected areas cover areas of high species count. One reason for this, as suggested by Veldmann and colleagues in 2015, is the preferential protection of tree species, so that shrub and flower species, which are equally rich and equally affected by agricultural expansion, are not adequately protected. In order to broaden our understanding of the effect land cover is having on biodiversity, other factors such as soil type and water availability should be included in the future. Similarly, dividing data into smaller time windows could give an indication of biodiversity change over time. This, compared to the MapBiomas dataset, would give a better understanding of the relationship between land cover change and biodiversity within the Cerrado.

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Riccardo Soldan
Period: 08/20/2018 to 09/20/2018
Research Area: Ecohidrology
Job Title: Modeling soil water fluxes in the Amazon forest
Supervisor: Laura De Simone Borma

Abstract: During my internship at CCST, I was responsible for using HYDRUS 1D to model soil water flows in the Amazon rainforest. About half of the Amazon rainforest is subject to seasonal droughts of 3 months or more. Despite this drought, several studies have shown that these forests, under a strongly seasonal climate, do not present significant water stress during the dry season. This is closely correlated with the rate of carbon dioxide fixation, as plant transpiration helps maintain proper gas exchange in the philosopher. Using data collected by Laura De Simone Borma’s laboratory over two years on an Amazon site, I tried to understand if Hydrus 1D was able to predict the evapotranspiration value that was measured. Interestingly, the model could not completely simulate the amount of water absorption that was measured on site during the dry season. This is mainly due to the fact that the amount of water measured in the soil was higher than predicted with the model during the dry season. During the simulation, we accounted for the presence of groundwater and root growth mediated by hydrotropism, but these processes have not yet been sufficient to match the amount of root water uptake measured at the site. Overall, this means that soil water flows in the Amazon are quite complex and water availability remains high during the dry season through complex and dynamic events. It is important to understand how soil moisture and root water abstraction are maintained during the dry season to better predict the effect of climate change and hence the longer dry season on growth and survival of the Amazon rainforest.

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Joshua Gowdy
Period: 08/02/2018 to 09/14/2018
Research Area: Renewable Energy
Job Title: Assessing Complementarity of Wind and Solar Energy for Optimizing Reliability of Future Hybrid Projects Across Brazil
Supervisor: Enio Bueno Pereira

Abstract: As of May 2017, 61.27% of Brazil’s electricity matrix is ​​served by large-scale hydropower (Pereira 2017). This represents the third largest installed capacity of hydropower in the world. While hydropower undoubtedly stands out in Brazil’s electricity mix, the Ministry of Mines and Energy aims, along with significant private sector support, to diversify the energy mix to reduce the risk of power shortages caused by droughts and, thus increase the energy. security (Global Data 2017). Future energy diversification and security strategies will increase the share of thermal, nuclear and alternative renewable energy sources, in particular photovoltaic wind and solar capacity expected to grow at a compound annual growth rate of 15% and 47% respectively. . the period from 2015 to 2025 (Global Data 2017). With the goals in mind: safety and reliability of electricity, grid optimization and adequacy of local supply and demand, as well as expected growth of previously untapped solar and wind resources in the energy mix, this preliminary study considers wind speed and the irradiance data measured as part of the SWERA project at three locations across Brazil from 2012 to 2014 to produce power generation data. It then assesses the possible complementarity of these energy resources by examining their anticompetition at various time scales. Before finally looking at hypothetical hybrid solar and wind power projects and varying the mix of the two features to optimize the reliability of the resulting power generation. Power generation reliability is assessed by a series of metrics reported indirectly by the needs and demands of consumers, network operators and government energy security targets. The study found a general principle of great importance in investigating the complementarity of energy resources – a strong reliance on the time scale between data points influences the anti-correlation value and resource variability. This also influences the combination of minimum variance of wind and solar energy as, as found in the study using simple variance addition formulas, this optimal can be predicted from correlation and relative variance alone. For all resource location variability increases as the time scale becomes thinner, which is an indication of volatility. This schedule dependency begs the question: “What reliability objective is the stakeholder interested in? And, crucially, at what time scale?” This study identifies this as a key consideration for justifying a specific resource balance for a hybrid energy project. This preliminary study raised some key questions about the scope of hybrid solar-wind power projects and their use of complementarity to increase reliability.The time scale at which complementarity is observed and the reliability of the power supply is required is an important factor that will be governed by the needs of energy stakeholders and investors.To bring this additional dimension to include the needs of consumers or network operators would require the use of demand data and data from other energy sources to report power supply reliability according to power demand The present presents a clear path for further study on this topic. This integrated approach to measuring power supply reliability and judging the benefits of hybrid projects reflects the integrated nature of electricity supply, but is incomplete until the geographical nature of electricity systems is considered. Thus, further study would include a much larger selection of measuring stations.