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There is a wide variety of drought indices, yet a consensus on suitable indices and temporal scales for monitoring streamflow drought remains elusive across diverse hydrological settings. Considering the growing interest in spatially distributed indices for ungauged areas, this study addresses the following questions: (i) What temporal scales of precipitation-based indices are most suitable to assess streamflow drought in catchments with different hydrological regimes? (ii) Do soil moisture indices outperform meteorological indices as proxies for streamflow drought? (iii) Are snow indices more effective than meteorological indices for assessing streamflow drought in snow-influenced catchments? To answer these questions, we examined 100 near-natural catchments in Chile with four hydrological regimes, using the standardised precipitation index (SPI), standardised precipitation evapotranspiration index (SPEI), empirical standardised soil moisture index (ESSMI), and standardised snow water equivalent index (SWEI), aggregated across various temporal scales. Cross-correlation and event coincidence analysis were applied between these indices and the standardised streamflow index at a temporal scale of 1 month (SSI-1), as representative of streamflow drought events. Our results underscore that there is not a single drought index and temporal scale best suited to characterise all streamflow droughts in Chile, and their suitability largely depends on catchment memory. Specifically, in snowmelt-driven catchments characterised by a slow streamflow response to precipitation, the SPI at accumulation periods of 12–24 months serves as the best proxy for characterising streamflow droughts, with median correlation and coincidence rates of approximately 0.70–0.75 and 0.58–0.75, respectively. In contrast, the SPI at a 3-month accumulation period is the best proxy over faster-response rainfall-driven catchments, with median coincidence rates of around 0.55. Despite soil moisture and snowpack being key variables that modulate the propagation of meteorological deficits into hydrological ones, meteorological indices are better proxies for streamflow drought. Finally, to exclude the influence of non-drought periods, we recommend using the event coincidence analysis, a method that helps assessing the suitability of meteorological, soil moisture, and/or snow drought indices as proxies for streamflow drought events.
A bifacial Photovoltaic (PV) simulation model is created by combining the optical View Factor matrix with electrical output simulation in python to analyse the energy density of bifacial systems. A discretization of the rear side of the bifacial modules allows a further investigation of mismatching and losses due to inhomogeneous radiation distribution. The model is validated, showing a deviation of -1.25 % to previous simulation models and giving hourly resolvedoutput data with a higher accuracy than existing software for bifacial PV systems.
Plants have certain characteristics which allow them to respond to various environmental conditions, like changes in climate, water loss in the soil, lack of minerals; among others. In some of these so-called traits, the responses to climatic phenomena such as drought can be evidenced through morphological adaptations (spines, succulent tissues, trichomes, among others) or physiological adaptations (regulation of water potential at the cellular level, the concentration of nutrients, etc.)
In certain areas of Brazil such as the Mata Atlântica biome, drought events are increasingly occurring and affecting human activities and the environment, and it is required to understand if tree species with traits adapted to dry conditions are occurring in drought-prone areas. For this reason, it is intended to find out the potential of using morphological functional traits of woody species as indicators of dry conditions in the transition zone of the Atlantic Forest. RJ Brazil.
Therefore, this work was carried out considering a field phase in a drought-prone area known as “Mata de Tabuleiros” or Semideciduous Seasonal Lowland Forest that belongs to the domain of the Mata Atlântica, there were selected morphological traits in order to know which of them can give a hint as drought tolerant traits. On the other side, there was searched in the Rio de Janeiro Botanical Garden JABOT database for species with recorded characteristics related to drought adaptations. For the traits in the field, and the selected species from the database was elaborated a Species Distribution Model SDM in order to know how some climatic variables allow the distribution of species and morphological traits.
As main result there was elaborated a set of trait indicators that can be considered for further analysis in the region; and also the results of the SDM obtained at large scale for the Mata Atlântica for the species selected from the database, and the SDM for the traits analyzed in the field in the Mata de Tabuleiros. Besides that, the consultations with experts in the subject were an important input that allowed to carry out this research. The use of morphological and functional traits is important to understand the interactions between organisms and their environment, in this case, to cope and tolerate a climate phenomenon like drought.
Keywords: Mata de Tabuleiros, Drought tolerance, Morphological traits, Species Distribution Modeling
Food insecurity, poor nutrition and poverty are closely linked and entail adverse consequences for the health and well-being of children and adults. They constitute major constraints to development efforts as they can imply lifelong negative effects on human development with impairments on physical and mental capacities of a population, resulting in an overall lower productivity and economic growth potential.
Urban agriculture has been advocated as a strategy to improve food security. This paper exemplifies an urban gardening project that addresses food security and economic resilience of the Syrian refugees and vulnerable Lebanese host communities executed in the suburbs of Beirut. The hypothesis underpinning this study is that urban agriculture holds the potential to contribute to increased food security and reduced urban poverty, by increasing the availability and accessibility to a variety of fresh foods that are rich in vital nutrients and by functioning as a source of livelihoods and income.
The brutality of the Syrian Civil War, it’s massive damage and destruction of housing and persecutions for ethnic cleansing led more than a quarter of its originally 24 million inhabitants to seek safety in neighboring countries and Europe. The war has severely hampered the stability and development throughout the region as hundreds of thousands of refugees have fled to neighboring countries where they often compete with host communities over housing, labor, water, food and land. In relative numbers the biggest burden fell on the riparian country Lebanon, currently holding the highest ratio of refugees to nationals in the world. The small Arab country has already been suffering from many pre-existing challenges as food insecurity and widespread poverty.
The high dependence on food assistance, limited access to income and uncertainties on the amount of food aid provided in each upcoming year, all contribute to an unstable and low food security status of Syrian refugee households in Lebanon with spill overs to vulnerable host communities. In 2017, 91% of Syrian families residing in Lebanon remained food insecure to some degree and the share of household’s falling into severe food insecurity keeps increasing with every year.
These numbers provide clear evidence that current efforts of providing food assistance are not sufficient to combat the repercussions of the crisis and get the situation under control.
The paper displays the impact of the urban gardening project on the food security and economic resilience of participating household’s, as well as lessons learned on the project design during and after the implementation phase. The sampling frame is comprised of Syrian and Lebanese families participating in the project. Primary data were derived from a survey using a questionnaire with a sample size of 41 households. The findings aim to enable stakeholders to improve the performance of similar projects in the future and support relevant government authorities, international aid institutions, non-profits and the civic society towards creating sustainable long-term solutions to increase the self-reliance of refugees by providing insights of the suitability of UA for multiple objectives and by highlighting potential challenges and risks.
With a rapidly growing population and urbanization, most modern slums (favelas) also proliferated in Brazil since the 1950s when many people left rural areas of Brazil and moved into the cities. Rio de Janeiro is one of those cities having a vast amount of favelas with poor living conditions. One of the main problems of electricity supply in favelas is illegal electricity use, called ‘Gato’ in Portuguese. Recent unexpected severe drought, economic crisis, and rapidly increased electricity price in Brazil affected the reliable supply of affordable electricity in favelas.
Considering abundant solar radiation of the country and the government’s willingness trying to shift the framework of energy supply from hydropower to renewable energy, this study analyzes the solar PV potentials to ensure a reliable supply of affordable electricity in favelas in Rio de Janeiro.
Literature reviews regarding solar PV development in Brazil, energy policy analysis in Brazil and electricity issues in favelas are revised. As a case study, the chosen favela ‘Babilônia’ is presented. The survey analysis about electricity consumption situation with social dimension targeting residences in Babilônia is implemented. Lastly, through economic analyses with cost-benefit calculation such as Internal Rate of Return (IRR), Net Present Value (NPV), Discounted Cash Flow, Payback period, Capital Asset Pricing Model (CAPM) and Weighted-Average Cost of Capital (WACC) models, this study develops the possible financing alternatives to implement a solar PV project with different scenario analyses in the current solar PV market and solar energy policy of Brazil.
The results of this study can be used as an aid to comprehend the electricity supply issue of the most vulnerable class in Brazil and the solar PV as a solution.
Researchers are always looking for innovative ways to collect the environmental data and ease the process of data collection on the field. Advancement in sensor technologies and drones has led to easy technological access to design custom solutions even with basic electronics and technical knowledge. This paper documents, construction and working of “ITT Smart Sense”, which is a low power, easy to use and cost effective environment monitoring system using wireless sensor network that runs autonomously on battery power for an extended period of time. Along with that, a UAV based platform, titled “ITT Smart Sense Fly”, focused on environmental monitoring and scientific research and is tailored to the needs of researchers has been proposed in this paper. This platform is comprised of an autonomous unmanned aerial vehicle (UAV)/Drone with a camera sensor, an autopilot mobile app for mission planning and other required Photogrammetry tools. The drone navigates over the area of interest based on a pre-programmed flight plan and captures a series of photographs using the on-board camera. The collected image data set is processed to create orthomosaics, high resolution maps and 3D point cloud. The proposed solutions were demonstrated with three distinct case studies.