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Electro-fuels (E-fuels) represent a potential solution for decarbonizing the maritime sector, including pleasure vessels. Due to their large energy requirements, direct electrification is not currently feasible. E-fuels, such as synthetic diesel, methanol, ammonia, methane and hydrogen, can be used in existing internal combustion engines or fuel cells in hybrid configurations with lithium batteries to provide propulsion and onboard electricity. This study confirms that there is no clear winner in terms of efficiency (the power-to-power efficiency of all simulated cases ranges from 10% to 30%), and the choice will likely be driven by other factors such as fuel cost, onboard volume/mass requirements and distribution infrastructure. Pure hydrogen is not a practical option due to its large storage necessity, while methanol requires double the storage volume compared to current fossil fuel solutions. Synthetic diesel is the most straightforward option, as it can directly replace fossil diesel, and should be compared with biofuels. CO2 emissions from E-fuels strongly depend on the electricity source used for their synthesis. With Italy's current electricity mix, E-fuels would have higher impacts than fossil diesel, with potential increases between +30% and +100% in net total CO2 emissions. However, as the penetration of renewable energy increases in electricity generation, associated E-fuel emissions will decrease: a turning point is around 150 gCO2/kWhel. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the irrigation water demand due to solar radiation in high-tech greenhouses using hydroponic systems in Turkey's Mediterranean and continental climates, and to determine the annual water consumption and storage capacity with harvested rainwater. Intensive greenhouse cultivation and the recent increase in modern greenhouse cultivation were important factors in selecting the provinces for the study. The chosen provinces were Antalya and Adana, with a Mediterranean climate, and Afyonkarahisar and Kırşehir, with a continental climate. In this research, depending on the production period, the amount of water consumed per unit of area in greenhouses in Antalya, which has a Mediterranean climate, was determined to be 1173.52 L m−2 per yr−1, and in Adana, it was 1109.18 L m−2 per yr−1. In the provinces of Afyonkarahisar and Kırşehir, where a continental climate prevails, water consumption was calculated to be 1479.11 L m−2 per yr−1 and 1370.77 L m−2 per yr−1, respectively. Storage volumes for the provinces of Antalya, Adana, Afyonkarahisar and Kırşehir were found to be 438.39 L m−2, 122.71 L m−2, 42.12 L m−2 and 43.65 L m−2, respectively. For the provinces of Antalya, Adana, Afyonkarahisar and Kırşehir, the rates of rainwater harvesting and meeting plants' water consumption were calculated to be 80.79%, 54.27%, 27.47% and 25.16%, respectively. In addition, the amount of water fee savings that could be achieved by rainwater harvesting was calculated to be USD 901.3 per yr−1 for Antalya, USD 835.3 per yr−1 for Adana, USD 247.6 per yr−1 for Afyonkarahisar and USD 210.2 per yr−1 for Kırşehir. As a result, rainwater harvesting will not only provide economic gain to enterprises but will also be important in reducing the negative effects of irregular rainfall regimes caused by climate change on underground and surface water resources. It was also concluded that enterprises should focus on popularizing rainwater harvesting. [ABSTRACT FROM AUTHOR]

The Nordic Sea overflow, being a significant driver of the thermohaline circulation, exerts a substantial influence on environmental dynamics in the Arctic and globally. A better understanding about the trend of the storage volume of the Nordic Seas Overflows is of paramount importance to a realistic assessment of the North Atlantic circulation and variability. EN4.2.2 reanalysis data were utilized to acquire the monthly average time series of overflow water storage volume in the Nordic Sea from 1950 to 2022. The storage volume demonstrates seasonal variations, with fluctuations of approximately 10% around the average. Over the period from 1980 to 2022, the average volume per decade exhibited a consistent decrease. Linear fitting of the annual average data estimated the overall relative change trend in the last 43 years to be -7.2 ± 2.6%. However, the quality of the EN4.2.2 data brings the average error of about 12% in the calculation of the overflow storage volume, which implies that the downward trend requires further validation. From a spatial standpoint, the Norwegian Sea, particularly the Lofoten Basin, is the primary region where overflow water storage volume in the Nordic seas have decreased. This decrease corresponds to an increase in ocean temperatures within the upper layer (0-600m) of both the Lofoten Basin and the Norwegian Basin. The warming of these regions has directly impacted the overflow water storage volume, leading to its reduction. It is noteworthy that the ocean temperature rise in the upper layer is more influenced by the Atlantic inflow rather than air-sea flux, particularly in the Norwegian Basin. This is attributed to the substantial increase in SST in the North Atlantic, which aligns with the warm current regions in the Atlantic Ocean, and the lack of statistical significance in linear trend of the air-sea heat flux. Furthermore, there has been a more rapid reduction in the overflow storage volume in the Norwegian Sea from 2011 to 2022. Specifically, the annual average overflow volume from 2018 to 2022 dropped below the previous lowest value. Concurrently, the salinity of the upper Norwegian Sea and the Atlantic inflow decreased considerably, while there has been no significant change in ocean temperature. Therefore, this short-term fluctuation is predominantly attributed to the decrease in Atlantic inflow salinity. Interestingly, the decrease in overflow water volume in the Nordic Seas does not follow a linear pattern in relation to increasing ocean temperature; instead, it exhibits an accelerating trend. If the ocean temperature rises by 1°C, the overflow water volume in the Nordic Seas will decrease to 86% of the total volume. Overall, the overflow water storage in the Norwegian Sea undergoes complex interannual variations and is notably influenced by the influx from the Atlantic Ocean. [ABSTRACT FROM AUTHOR]

Error-correcting codes (ECCs) employed in the state-of-the-art DNA digital storage (DDS) systems suffer from a trade-off between error-correcting capability and the proportion of redundancy. To address this issue, in this study, we introduce soft-decision decoding approach into DDS by proposing a DNA-specific error prediction model and a series of novel strategies. We demonstrate the effectiveness of our approach through a proof-of-concept DDS system based on Reed-Solomon (RS) code, named as Derrick. Derrick shows significant improvement in error-correcting capability without involving additional redundancy in both in vitro and in silico experiments, using various sequencing technologies such as Illumina, PacBio and Oxford Nanopore Technology (ONT). Notably, in vitro experiments using ONT sequencing at a depth of 7× reveal that Derrick, compared with the traditional hard-decision decoding strategy, doubles the error-correcting capability of RS code, decreases the proportion of matrices with decoding-failure by 229-fold, and amplifies the potential maximum storage volume by impressive 32 388-fold. Also, Derrick surpasses 'state-of-the-art' DDS systems by comprehensively considering the information density and the minimum sequencing depth required for complete information recovery. Crucially, the soft-decision decoding strategy and key steps of Derrick are generalizable to other ECCs' decoding algorithms. [ABSTRACT FROM AUTHOR]

In recent decades, increased water demand combined with the effects of climate change has endangered water availability in many regions. In this context, sustainable water management has become a priority, seeking to balance human needs with the conservation of aquatic ecosystems. In the Duero basin (Spain), the availability of water is especially relevant for agricultural purposes, representing 93% of the total water needs. This study focuses on identifying and assessing the short-term sustainability of irrigated crop production in the Duero River basin. The maximum potential availability of surface water for irrigation was estimated and compared with the short-term agricultural surface water demand. The analysis was based on the use of a high-spatial-resolution (500 × 500 m) GIS-based model named WAAPA, and three indexes were used to evaluate and analyze the results. The results show that by analyzing the river basin in an aggregate form, the demands for irrigation were met, in which the reservoirs played an important role. When the analysis was downscaled to tributaries or even small streams, non-sustainable situations were identified. This shows the importance of using high-spatial-resolution models to improve, maintain, and achieve sustainability in the production of irrigated crops. [ABSTRACT FROM AUTHOR]

Permeability is an essential factor used for evaluating the commercial exploitation of unconventional energy. The pressure pulse decay method is one of the most effective methods to measure permeability and has been improved by adding a pressure transducer upstream and a chamber upstream and downstream. The relationship between the pulse pressure and equilibrium time under different storage volumes is investigated based on a developed apparatus. Moreover, the effect of compressive storage on permeability measurements has been examined by comparing the Brace's et al.'s solution and Jones' solution. The following results were obtained for the constant injection pressure. 1) The equilibrium pressure increases with a decrease in the upstream storage volume and decreases with an increase in the downstream storage volume. 2) The equilibrium time increases with an increase in the storage volume, and the similar volume of the upstream and downstream can accelerate the test procedure. 3) A linear relationship between the storage volume and equilibrium time is not apparent when the volume of the upstream and downstream are asymmetric. However, this linear relationship is evident when the volume of the upstream and downstream are symmetrical. 4) The influence of the downstream storage volume is more significant than the upstream volume on the measurement of permeability. The results are of guiding significance for selecting the proper storage volume to measure permeability. [ABSTRACT FROM AUTHOR]

Experimental regulating parameters of the non-stationary expansion of air inside a bladder-type hydraulic accumulator, working with the simple short pipeline, are presented in the paper. The technique of continuous online monitoring of changes in time of volume and absolute air pressure inside the hydraulic accumulator during the discharge process has been improved. Three series of experimental studies of transient gas processes inside the accumulator at different values of the average volume flow rate are made. Tendencies of change of the integral parameters of the hydraulic accumulator are obtained and analyzed depending on the serial number of the discharge cycle. A general dependence of dimensionless storage volume Kreg on the polytropic index n in series # 1–3, approximated by single power-law dependence, is obtained. The systematic changes of integral parameters in each subsequent discharge cycle can be explained by the non-stationary transient thermodynamic processes in air inside the accumulator until the thermodynamic equilibrium with the ambient air parameters is reached.

Population migration in big cities led to an increase in the complexity of the water supply and distribution systems, as well as of water storage volumes. Dimensioning data of the water storage tank must be periodically analyzed and brought up to date based on in situ measurements. This report analyzes the hourly, daily and monthly water consumption in some Romanian residential areas belonging to the big cities, for the year 2017. Further, the percentage parameters n were calculated and then used to compensate the hourly water demand of the consumers (WVHDC). The obtained values of the percentage parameters for 2017 were compared to values corresponding to the years: 1966, 1977, 1995, and 2006. For 2017, the minimum percentage parameter increased to 2.41 while the maximum decreased to 5.44 compared to the other years. A smoother variation in 2017 hourly water consumption was registered compared to 2006. Also, the WVHDC decreased in 2017 by 50 % compared to 1966 and by 4 % from 2006. The results confirmed the need of a periodical update of the percentage parameters and of the water storage volume. [ABSTRACT FROM AUTHOR]

Sediment accumulation in a river reservoir is studied by stochastic time series models and analytical approach. The first-order moving average process is found the best for the suspended sediment discharge time series of the Juniata River at Newport, Pennsylvania, USA. Synthetic suspended sediment discharges are first generated with the chosen model after which analytical expressions are derived for the expected value and variance of sediment accumulation in the reservoir. The expected value and variance of the volume of sediment accumulation in the reservoir are calculated from a thousand synthetic time series each 38 years long and compared to the analytical approach. Stochastic and analytical approaches perfectly trace the observation in terms of the expected value and variability. Therefore, it is concluded that the expected value and variance of sediment accumulation in a reservoir could be estimated by analytical expressions without the cost of synthetic data generation mechanisms. [ABSTRACT FROM AUTHOR]

By the year 2017 Cirata reservoir has already operated for more than 30 years with a lifetime plan of 100. The annual sedimentation rate plan of Cirata Reservoir was 5.7 x 106 m³, but as calculated in 2017 the annual sedimentation rate increased to 8.4 x 106 m³, which has increased 77.78%. To predict the remaining lifetime of Cirata Reservoir, empiric method of reservoir lifetime was used alongside a new approach to predict the storage volume of a river in years coming by using a hydrometric and sediment approach. The result of Cirata Reservoir remaining lifetime using empirical method is 65 years, this number then used as reference to predict the remaining volume of Cirata Reservoir dead storage using sediment approach. Reservoir lifetime prediction by hydrometric and sediment approach uses the same principle by understanding that a reservoir lifetime is over by the time the dead storage full. What makes this approach differ from the empirical method is that this approach does not only focus on the when dead storage will be full, but also calculating or predicting the changes of storage volume in each elevation. Using this approach, the result shows that the volume of dead storage will already be full and exceeds its capacity by 41.9 x 106 m³ in the next 65 years. Then by using the same approach and by trials and errors, the time needed to fully fill the dead storage is 60 years, or the reservoir will be defunct in 2077. [ABSTRACT FROM AUTHOR]

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Currently, China is experiencing a phase of rapid urbanization. With the frequent occurrence of extreme rainfall events within the context of climate change, the problem of heavy rainfall and waterlogging in many cities is very prominent. In November 2020, China issued a proposal for the construction of sponge cities across the entire region to significantly enhance the rainfall flood prevention and drainage capacity of cities and effectively improve the resilience of sponge city systems for flooding management. Therefore, this paper selected the Zhu pai-chong watershed in Nanning with frequent waterlogging disasters as an example. Based on underlying surface information, We used a coupled SWMM-LISFOOD model to simulate runoff and waterlogging processes and analyze the spatial and temporal evolution characteristics of the basin under 10 designed rainstorm return periods (0.25a-50a). The results confirm the substantial spatial and temporal variabilities of the runoff coefficient in the study area; impermeability was the main factor contributing to high runoff coefficient values. The spatial distribution characteristics of inundation area was general dispersion and local linear aggregation. Furthermore, this study assessed the effect of the control rate of blue‒green‒gray facilities on the actual storms, and the value ranged from only 48.6% (0.25a)-24.05% (50a). This study quantified the two-dimensional distribution of rainfall storage volume thresholds with or without considering the discharged from the pipe network. Quantitative mapping between the elements of "rainfall-storage volume of blue‒green‒gray facilities-runoff-drainage capacity of the pipe network-waterlogging level" was conducted within the study area as an example. Finally, an overall technical process scheme for rainfall and waterlogging management was proposed. The scheme covered the hydrological‒hydraulic mechanism, storage function of sponge facilities, engineering control response, nonengineering measures and intelligent management of rainfall and waterlogging during sponge city construction, which could provide critical scientific support for effective promotion of the construction of sponge cities in China. [Display omitted] • The runoff waterlogging under different design rainstorm scenarios was simulated. • A quantitative method of the regulation level of the total rainstorm is presented. • The impact of pipe network drainage on control level of rainstorm is quantified. • A system plan to deal with rainstorm waterlogging of sponge city was summarized. [ABSTRACT FROM AUTHOR]

The construction of four dams on the Angara River, which flows out from Lake Baikal, has resulted in the creation of the largest water storage system in the world. The first dam is situated 55 km away from the location where the river flows out from Lake Baikal and it impounds the Irkutsk Reservoir holding 2.1 km of water and increasing water level in Lake Baikal. In this manner, the volume of water in the Lake has increased by about 37 km. The second dam, which is located at Bratsk, is 125 m high at its maximum, and has caused the flooding of a 570 km-long reach of the Angara River valley. The Bratsk Reservoir can hold 168.2 km of water. The third reservoir, with its dam at Ust-Ilimsk, has a capacity of 58.9 km. Outflow across the dam cross-section is about 3,000 m s of water. This partly serves to fill the fourth reservoir which is currently being constructed, the Boguchany Reservoir, impounded by a dam at Kodinsk. This reservoir will hold 58.2 km of water. Management of this storage is used to prevent floods, but the main objective is to use the reservoirs as sources of hydroelectric power. [ABSTRACT FROM AUTHOR]

Terrain elevation is essential for land management, navigation, and earth science applications. Remote sensing advancements have led to an increase in the availability of a range of digital elevation models with global to quasi-global land coverage. However, the generation of these models in water bodies requires specialized approaches, such as the delimitation of the shorelines (isobaths) of lakes over time. Therefore, the processing costs are high in complex areas with many lakes. Currently, there is no systematic topographic mapping of lakes and channels in large and complex floodplains using remote sensing data. We present here the first high-resolution topographic mapping (30 m) of the non-forested portion of the middle-lower Amazon floodplain using a new method based on in-situ Amazon river water levels and a flood-frequency map derived from the Landsat Global Surface Water Dataset. Validation using locally derived bathymetry showed a root mean square error (RMSE) of 0.89 m for floodplain elevation and a good representation of spatial patterns with Pearson's correlation coefficient of 0.77. Our approach for improving topographic representation in open water areas is an alternative to SRTM3 DEM or MERIT DEM, which represents these areas as a flat surface. We also generated the Amazon River bathymetry using nautical charts from the Brazilian Navy (average RMSE of 7.5 m and bias of 5 m), and floodplain depths maps corresponding to the high- and low-water periods of the river flood wave. The results show that the storage volume in the open-water floodplain varies 104.3 km3 on average each year (from 11.9 km3 in low-water to 116.2 km3 in high-water). The method can be applied to any temporarily flooded area to provide the often missing underwater digital topographic data required for hydrological, ecological, and geomorphological studies. The data set developed in this study can be found at https://doi.org/ 10.17632/vn599y9szb.1. Unlabelled Image • Landsat flood frequency-based method applied for floodplain topography estimation. • 0.9 m floodplain elevation RMSE after vegetation bias removal with ICESat-2. • River bathymetry (~1100 km extension) obtained from nautical charts; RMSE of 7.5 m. • High-resolution (30 m) water depth and topography maps for middle-lower Amazon. • Storage volume on floodplain open-water areas varies 104.3 km3 on average each year. [ABSTRACT FROM AUTHOR]