The Precipitationshed : Concepts, Methods, and Applications

Human societies are reliant on the functioning of the hydrologic cycle. The atmospheric branch of this cycle, often referred to as moisture recycling in the context of land-to-land exchange, refers to water evaporating, traveling through the atmosphere, and falling out as precipitation. Similar to the surface water cycle that uses the watershed as the unit of analysis, it is also possible to consider a ‘watershed of the sky’ for the atmospheric water cycle. Thus, I explore the precipitationshed - defined as the upwind surface of the Earth that provides evaporation that later falls as precipitation in a specific place. The primary contributions of this dissertation are to (a) introduce the precipitationshed concept, (b) provide a quantitative basis for the study of the precipitationshed, and (c) demonstrate its use in the fields of hydrometeorology, land-use change, social-ecological systems, ecosystem services, and environmental governance. In Paper I, the concept of the precipitationshed is introduced and explored for the first time. The quantification of precipitationshed variability is described in Paper II, and the key finding is that the precipitationsheds for multiple regions are persistent in time and space. Moisture recycling is further described as an ecosystem service in Paper III, to integrate the concept into the existing language of environmental sustainability and management. That is, I identify regions where vegetation more strongly regulates the provision of atmospheric water, as well as the regions that more strongly benefit from this regulation. In Paper IV, the precipitationshed is further explored through the lens of urban reliance on moisture recycling. Using a novel method, I quantify the vulnerability of urban areas to social-ecological changes within their precipitationsheds. In Paper V, I argue that successful moisture recycling governance will require flexible, transboundary institutions that are capable of operating within complex social-ecological systems. I conclude that, in the future, the precipitationshed can be a key tool in addressing the complexity of social-ecological systems. 

Avaliação da eficiência do sistema de abastecimento de água da APA

A água é um recurso essencial e escasso, como tal, é necessário encontrar medidas que permitam o seu uso de modo sustentável e garantam a proteção do meio ambiente. Devido a esta crescente preocupação assiste-se a um movimento legislativo, nacional e internacional, no sentido de garantir o desenvolvimento sustentável. Surge assim, a Diretiva Quadro da Água e a Lei da Água, que é complementada com legislação diversa. Como elemento constituinte do ciclo urbano da água, os Sistemas de Abastecimento têm sofrido evoluções nem sempre adequadas. É neste contexto que, em Portugal, nascem as diversas ferramentas para a melhoria da gestão dos recursos hídricos. As Entidades Gestoras têm como finalidade a gestão eficiente do bem água, e dispõe de dois importantes instrumentos, o Programa Nacional para o Uso Eficiente da Água e o Guia para o “controlo de perdas de água em sistemas públicos de adução e distribuição”(ERSAR). Esta Gestão passa, não só pela abordagem da problemática das perdas de água, reais e aparentes, como também pela análise do comportamento que origina o desperdício. A APA, enquanto entidade gestora, procura maximizar a eficiência do seu sistema de abastecimento, para tal, foram aplicadas as ferramentas propostas pelo ERSAR. Concluindo-se que este sistema tem um total de perdas de água de 34%, devendo-se estas perdas essencialmente ao envelhecido parque de contadores e perdas nos ramais de distribuição (teórico). As perdas comerciais representam cerca de 69%, o que revela que os volumes de água não faturados (medidos ou não) são muito elevados. Por outro lado, a realização do cálculo do Balanço Hídrico e dos índices de desempenho permitem classificar a performance do sistema de abastecimento e compará-la com os seus objetivos de gestão. Atendendo ao volume de água perdido nos ramais, foram efetuadas medições noturnas, verificando-se que no Porto de Pesca Costeira existe um volume de água escoado não justificado. Neste sentido, elaborou-se um plano de ação para aumentar a eficiência do sistema, ou seja, reduzir as perdas totais de 34% para 15%.

North American Monsoon GPS Transect Experiment 2013

Ten GPS-Met stations were installed in northwest Mexico from June - September 2013. Each station included a Trimble NetR9 GPS receiver for PWV and a Vaisala WXT520 surface meteorological package measuring wind speed and direction, air temperature, humidity, pressure and precipitation. The geographic location, elevation and data period for each station are provided in Serra et al. (2016). The GPS receiver at Rayon failed on July 16, 21 days after installation, thus these data are not included in the archive but are available upon request (yserra@uw.edu). Data include 1-min surface meteorological variables, while the GPS PWV is calculated at 5-min intervals. A full description of the experiment can be found in Serra et al., 2016: Bull. Am. Meteor. Soc., doi: 10.1175/BAMS-D-14-00250.1.

Appropriate technologies and natural systems for wastewater treatment in low- and middle-income countries

Wastewater management is an environmental and social burden that primarily affects populations in Low- and Middle-Income Countries and the global environment. Wastewater collection, treatment, and reuse have become urgent, especially considering that 80% of the world's wastewater is untreated or improperly treated and discharged directly into water bodies. In recent years, the role of wastewater treatment plants in a sustainable water cycle has become even more critical, as they are the final destination of the collected wastewater. Indeed, the management of wastewater treatment plants should play an essential role in achieving SDG target 6.3 of the United Nations 2030 Agenda for SD. In this context, water reuse, especially wastewater reuse, plays a key role. This research focuses on investigating the valorization of wastewater resources applying Appropriate Technologies and Natural Systems for wastewater treatment in two different Low- and Middle-Income Countries, the Palestinian Territories and Sub-Saharan Africa. The research objectives are: (1) Determine the characteristics and quality of wastewater in the two case studies analysed. (2) Identify Appropriate Technology to be used in the Palestinian Territories to treat wastewater for reuse in agriculture. (3) Assess the environmental, economic, and social impacts of this project. (4) Assess the feasibility of using natural wetlands for household wastewater treatment in Sub-Saharan region. The first study, conducted in Rafah, Gaza Strip, showed that implementing existing primary treatment plant with a natural secondary treatment plant properly optimized the wastewater quality for reuse in agriculture and was suitable for the study area. The second case study was conducted in Cape Coast, Ghana. It shows that the natural wetland studied is currently overly polluted and threatened by various anthropogenic factors that cannot remove pollutants from the incoming domestic wastewater. Therefore, some recommendations were made in order to improve the efficiency of this natural wetland.

How to govern the urban hydrosocial cycle : archaeo-genealogy of hydromentalities in the Swiss urban water sector between 1850 and 1950

Switzerland appears to be a privileged place to investigate the urban political ecology of tap water because of the specificities of its political culture and organization and the relative abundance of drinking water in the country. In this paper, we refer to a Foucauldian theorization of power that is increasingly employed in the social sciences, including in human geography and political ecology. We also implement a Foucauldian methodology. In particular, we propose an archaeo-genealogical analysis of discourse to apprehend the links between urban water and the forms of governmentality in Switzerland between 1850 and 1950. Results show that two forms of governmentality, namely biopower and neoliberal governmentality, were present in the water sector in the selected period. Nonetheless, they deviate from the models proposed by Foucault, as their periodization and the classification of the technologies of power related to them prove to be much more blurred than Foucault's work, mainly based on France, might have suggested.

Flooded rice yield as affected by levels of water salinity in different stages of its cycle

Losses of productivity of flooded rice in the State of Rio Grande do Sul, Brazil, may occur in the Coastal Plains and in the Southern region due to the use of saline water from coastal rivers, ponds and the Laguna dos Patos lagoon, and the sensibility of the plants are variable according to its stage of development. The purpose of this research was to evaluate the production of rice grains and its components, spikelet sterility and the phenological development of rice at different levels of salinity in different periods of its cycle. The experiment was conducted in a greenhouse, in pots filled with 11 dm³ of an Albaqualf. The levels of salinity were 0.3 (control), 0.75, 1.5, 3.0 and 4.5 dS m-1 kept in the water layer by adding a salt solution of sodium chloride, except for the control, in different periods of rice development: tillering initiation to panicle initiation; tillering initiation to full flowering; tillering initiation to physiological maturity; panicle initiation to full flowering; panicle initiation to physiological maturity and full flowering to physiological maturity. The number of panicles per pot, the number of spikelets per panicle, the 1,000-kernel weight, the spikelet sterility, the grain yield and phenology were evaluated. All characteristics were negatively affected, in a quadratic manner, with increased salinity in all periods of rice development. Among the yield components evaluated, the one most closely related to grain yields of rice was the spikelet sterility.

Histological description of seminiferous epithelium and cycle length of spermatogenesis in the water shrew Neomys fodiens (Mammalia: Soricidae).

Recently, we examined the spermatogenesis cycle length in two shrews species, Sorex araneus characterized by a very high metabolic rate and a polyandric mating system (sperm competition) resulting in a short cycle and Crocidura russula characterized by a much lower metabolic rate and a monogamous mating system showing a longer cycle. In this study, we investigated the spermatogenesis cycle in Neomys fodiens showing an intermediate metabolic rate. We described the stages of seminiferous epithelium according to the spermatid morphology method and we calculated the cycle length of spermatogenesis using incorporation of 5-bromodeoxyuridine into DNA of the germ cells. Twelve males were injected intraperitoneally with 5-bromodeoxyuridine, and the testes were collected. For cycle length determination, we applied a recently developed statistical method. The calculated cycle length is 8.69 days and the total duration of spermatogenesis based on 4.5 cycles is approximately 39.1 days, intermediate between the duration of spermatogenesis of S. araneus (37.6 days) and C. russula (54.5 days) and therefore congruent with both the metabolic rate hypothesis and the sperm competition hypothesis. Relative testes size of 1.4% of body mass indicates a promiscuous mating system.

Systematic study of the impact of fresh water fluxes on the glacial carbon cycle

During glacial periods, atmospheric CO2 concentration increases and decreases by around 15 ppm. At the same time, the climate changes gradually in Antarctica. Such climate changes can be simulated in models when the AMOC (Atlantic Meridional Oceanic Circulation) is weakened by adding fresh water to the North Atlantic. The impact on the carbon cycle is less straightforward, and previous studies give opposite results. Because the models and the fresh water fluxes were different in these studies, it prevents any direct comparison and hinders finding whether the discrepancies arise from using different models or different fresh water fluxes. In this study we use the CLIMBER-2 coupled climate carbon model to explore the impact of different fresh water fluxes. In both preindustrial and glacial states, the addition of fresh water and the resulting slow-down of the AMOC lead to an uptake of carbon by the ocean and a release by the terrestrial biosphere. The duration, shape and amplitude of the fresh water flux all have an impact on the change of atmospheric CO2 because they modulate the change of the AMOC. The maximum CO2 change linearly depends on the time integral of the AMOC change. The different duration, amplitude, and shape of the fresh water flux cannot explain the opposite evolution of ocean and vegetation carbon inventory in different models. The different CO2 evolution thus depends on the AMOC response to the addition of fresh water and the resulting climatic change, which are both model dependent. In CLIMBER-2, the rise of CO2 recorded in ice cores during abrupt events can be simulated under glacial conditions, especially when the sinking of brines in the Southern Ocean is taken into account. The addition of fresh water in the Southern Hemisphere leads to a decline of CO2, contrary to the addition of fresh water in the Northern Hemisphere.

Thermal design of a tray-type distillation column of an ammonia/water absorption refrigeration cycle

The goal of this paper is to present an analysis of a segmented weir sieve-tray distillation column for a 17.58 kW (5 TR) ammonia/water absorption refrigeration cycle. Balances of mass and energy were performed based on the method of Ponchon-Savarit, from which it was possible to determine the ideal number of trays. The analysis showed that four ideal trays were adequate for that small absorption refrigeration system having the feeding system to the column right above the second tray. It was carried out a sensitivity analysis of the main parameters. Vapor and liquid pressure drop constraint along with ammonia and water mass flow ratios defined the internal geometrical sizes of the column, such as the column diameter and height, as well as other designing parameters. Due to the lack of specific correlations, the present work was based on practical correlations used in the petrochemical and beverage production industries. The analysis also permitted to obtain the recommended values of tray spacing in order to have a compact column. The geometry of the tray turns out to be sensitive to the charge of vapor and, to a lesser extent, to the load of the liquid, being insensible to the diameter of tray holes. It was found a column efficiency of 50%. Finally, the paper presents some recommendations in order to have an optimal geometry for a compact size distillation column. (c) 2011 Elsevier Ltd. All rights reserved.

Modeling the marine aragonite cycle: changes under rising carbon dioxide and its role in shallow water CaCO3 dissolution

The marine aragonite cycle has been included in the global biogeochemical model PISCES to study the role of aragonite in shallow water CaCO3 dissolution. Aragonite production is parameterized as a function of mesozooplankton biomass and aragonite saturation state of ambient waters. Observation-based estimates of marine carbonate production and dissolution are well reproduced by the model and about 60% of the combined CaCO3 water column dissolution from aragonite and calcite is simulated above 2000 m. In contrast, a calcite-only version yields a much smaller fraction. This suggests that the aragonite cycle should be included in models for a realistic representation of CaCO3 dissolution and alkalinity. For the SRES A2 CO2 scenario, production rates of aragonite are projected to notably decrease after 2050. By the end of this century, global aragonite production is reduced by 29% and total CaCO3 production by 19% relative to pre-industrial. Geographically, the effect from increasing atmospheric CO2, and the subsequent reduction in saturation state, is largest in the subpolar and polar areas where the modeled aragonite production is projected to decrease by 65% until 2100.

Variability of mesospheric water vapor above Bern in relation to the 27-day solar rotation cycle

Many studies investigated solar–terrestrial responses (thermal state, O₃ , OH, H₂O) with emphasis on the tropical upper atmosphere. In this paper the Focus is switched to water vapor in the mesosphere at a mid-latitudinal location. Eight years of water vapor profile measurements above Bern (46.88°N/7.46°E) are investigated to study oscillations with the Focus on periods between 10 and 50 days. Different spectral analyses revealed prominent features in the 27-day oscillation band, which are enhanced in the upper mesosphere (above 0.1 hPa, ∼64 km) during the rising sun spot activity of solar cycle 24. Local as well as zonal mean Aura MLS observations Support these results by showing a similar behavior. The relationship between mesospheric water and the solar Lyman-α flux is studied by comparing thesi-milarity of their temporal oscillations. The H₂O oscillation is negatively correlated to solar Lyman-α oscillation with a correlation coefficient of up to −0.3 to −0.4, and the Phase lag is 6–10 days at 0.04 hPa. The confidence level of the correlation is ≥99%. This finding supports the assumption that the 27-day oscillation in Lyman-α causes a periodical photo dissociation loss in mesospheric water. Wavelet power spectra, cross-wavelet transform and wavelet coherence analysis (WTC)complete our study. More periods of high common wavelet power of H₂O and solar Lyman-α are present when amplitudes of the Lyman-α flux increase. Since this is not a measure of physical correlation a more detailed view on WTC is necessary, where significant (two sigma level)correlations occur intermittently in the 27 and 13-day band with variable Phase lock behavior. Large Lyman-α oscillations appeared after the solar super storm in July 2012 and the H₂O oscillations show a well pronounced anticorrelation. The competition between advective transport and photo dissociation loss of mesospheric water vapor may explain the sometimes variable Phase relationship of mesospheric H₂O and solar Lyman-α oscillations. Generally, the WTC analysis indicates that solar variability causes observable photochemical and dynamical processes in the mid-latitude mesosphere.

Comparative Life Cycle Assessment of the Conventional Façade SOS Natura and the Natural Water Tank Façade

The construction industry produces great environmental impacts to the planet. In order to tackle this problem, the European Union has put into effect Regulation No 305/2011, which compels the construction products manufacturers to carry out environmental performance studies of these products and thus make public the impact they cause on the environment. The aim of this research is to make known the environmental impacts of the SOS Natura Conventional Façade (CF) solution, obtained within the research project "SOS Natura, Vegetal Architectural Solutions" developed by the Department of Construction and Technology in Architecture of the School of Architecture of the Technical University of Madrid (Spain). In addition, we report an environmental comparative with the Natural Water Tank Façade (NWTF), studied previously by the same work group and included in the same research project.We present as well an uncertainty analysis for both façades. Following the study conducted we conclude that the NWTF profile has a slightly better environmental behaviour when compared to the CF profile for the entire life cycle in most of the impact categories analysed in this study. However it should also be noted that, in detail and at stage level, the NWTF presents a higher environmental impact than the CF.