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Abstract Wind climate analysis and modelling is of most importance during site selection for offshore wind farm development. In this regard, reliable long-term wind data are required. Buoy measurements are considered as a reference source in relevant applications including evaluation and calibration of wind data obtained from less reliable sources, combined assessment, blending and homogenization of multi-source wind data, etc. Most of these applications are based on regression techniques elaborated by using the principle of ordinary least squares (OLS). However, wind data usually contain several outliers, which may question the validity of the regression analysis, if not properly considered. This study is focused on the implementation of the most important robust regression methods, which can identify and reveal outliers, and retain at the same time their efficiency. Long-term reference wind data series obtained from buoys at six locations in the Mediterranean Sea are used to calibrate hindcast (model) wind data by applying robust methods and OLS. The obtained results are compared according to several statistical measures. The effects of the calibration methods are also assessed with respect to the available wind power potential. The results clearly suggest that least trimmed squares and L1-estimator perform in all respects better than OLS.

The tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was operated during leg 4 of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC). The balloon was operated from the Balloon Town site in the central observatory, close to RV Polarstern (Shupe et al., 2022, Elementa). Balloon payload included an extended meteorological package, an ultrasonic anemometer package, a broadband radiation package, the video ice particle sampler, and the cubic aerosol measurement platform. An overview showing the value of the combined observation is displayed by Lonardi et al. (in review). The data processing is described in Pilz et al. (in preparation). The present dataset covers the solar irradiances measured by the broadband radiation package on 18 flights between 29 June and 27 July 2020. Profiles of downward and upward raw solar radiation, latitude, longitude, roll, pitch, yaw, and radiometer icing flag. Geopotential height is derived from the pressure.

Acid–base disturbances caused by environmental factors and physiological events including feeding have been well documented in several fish species, but little is known about the impact of dietary electrolyte balance (dEB). In the present study, we investigated the effect of feeding diets differing in dEB ( − 100, 200, 500 or 800 mEq/kg diet) on the growth, nutrient digestibility and energy balance of Nile tilapia. After 5 weeks on the test diet, the growth of the fish was linearly affected by the dEB levels (P< 0·001), with the lowest growth being observed in the fish fed the 800 dEB diet. The apparent digestibility coefficient (ADC) of fat was unaffected by dEB, whereas the ADC of DM and protein were curvilinearly related to the dEB levels, being lowest and highest in the 200 and 800 dEB diets, respectively. Stomach chyme pH at 3 h after feeding was linearly related to the dEB levels (P< 0·05). At the same time, blood pH of the heart (P< 0·05) and caudal vein (P< 0·01) was curvilinearly related to the dEB levels, suggesting the influence of dEB on postprandial metabolic alkalosis. Consequently, maintenance energy expenditure (MEm) was curvilinearly related to the dEB levels (P< 0·001), being 54 % higher in the 800 dEB group (88 kJ/kg0·8per d) than in the 200 dEB group (57 kJ/kg0·8per d). These results suggest that varying dEB levels in a diet have both positive and negative effects on fish. On the one hand, they improve nutrient digestibility; on the other hand, they challenge the acid–base homeostasis (pH) of fish, causing an increase in MEm, and thereby reduce the energy required for growth.

A “Well-to-Propeller” Life Cycle Assessment of maritime transport was performed with a European geographical focus. Four typical types of vessels with specific operational profiles were assessed: a container vessel and a tanker (both with 2-stroke engines), a passenger roll-on/roll-off (Ro-Pax) and a cruise vessel (both with 4-stroke engines). All main engines were dual fuel operated with Heavy Fuel Oil (HFO) or Liquefied Natural Gas (LNG). Alternative onshore and offshore fuel supply chains were considered. Primary energy use and greenhouse gas emissions were assessed. Raw material extraction was found to be the most impactful life cycle stage (~90% of total energy use). Regarding greenhouse gases, liquefaction was the key issue. When transitioning from HFO to LNG, the systems were mainly influenced by a reduction in cargo capacity due to bunkering requirements and methane slip, which depends on the fuel supply chain (onshore has 64% more slip than offshore) and the engine type (4-stroke engines have 20% more slip than 2-stroke engines). The combination of alternative fuel supply chains and specific operational profiles allowed for a complete system assessment. The results demonstrated that multiple opposing drivers affect the environmental performance of maritime transport, a useful insight towards establishing emission abatement strategies.

Time series data, sensor layout, and wave calibration summaries for the wave height measurements for the 10 calibration sea states for the 1:20 scale testing of the Wave Energy Prize (WEP) at the US Navy's Maneuvering and Seakeeping (MASK) Basin at the Naval Surface Warfare Center in Carderock, Maryland. Measurements were made in the test area and upstream of the test area.

The tethered balloon system BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) was operated during leg 4 of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC). The balloon was operated from the Balloon Town site in the central observatory, close to RV Polarstern (Shupe et al., 2022, Elementa). Balloon payload included an extended meteorological package, an ultrasonic anemometer package, a broadband radiation package, the video ice particle sampler, and the cubic aerosol measurement platform. An overview showing the value of the combined observation is displayed by Lonardi et al. (in review). The data processing is described in Pilz et al. (in preparation). The present dataset covers the solar irradiances measured by the broadband radiation package on 18 flights between 29 June and 27 July 2020. Profiles of downward and upward raw solar radiation, latitude, longitude, roll, pitch, yaw, and radiometer icing flag. Geopotential height is derived from the pressure.

Filter feeding invertebrates are a relevant component of fouling assemblages with a pivotal role in ecological processes, since they improve water quality, enhance habitat heterogeneity and transfer organic matter from the water column to the benthos. They modulate the availability of resources to other species, with effects on the density and behavior of the surrounding macrofauna. The fanworm Sabella spallanzanii, one of the largest and most abundant Mediterranean filter feeders, provides a shelter for predation and a secondary substrate for algae and settlement for sessile invertebrates. We tested its role in driving the structure of fouling assemblages, through a removal experiment.The experiment was one-year-long, with four sampling times. The effect of the removal on the fouling community was marginal in terms of species richness and evenness, while the biomass showed important differences, with a constant increase over time with higher values in the samples containing S. spallanzanii. At the end of observations, the biomass reached the value of 3917 g DW m-2 in controls and 2073 g DW m-2 in treatments. The empty space left by fanworms was not used by other species with similar biomasses. It is possible that the functioning of fouling communities may, in the event of loss of species, fluctuate in terms of biomass mobilization to different compartments, either towards the pelagic compartment or to the detritus chain. In systems with reduced water turnover, this by-pass can have important consequences in terms of stability and ecological balance.

All data were generated by the authors. All individuals identifying invertebrates had over 10 years of experience and hold the Natural History Museum IdQ EO62 Identification of Freshwater Macroinvertebrate Species. All data produced were checked for errors before data was accepted. As chemical data were generated, checks were made to ensure accuracy (certified reference materials) and precision (repeat measurements) were within accepted tolerance limits. We also ensured measured values fit within those of calibration standards and, if necessary, re-analysed samples diluted to fall within the calibration range. For data generated via mass spectrometry, beam areas of all measured mass-to-charge ratios were corrected for drift offline using control standards. All data were checked to ensure reported values were above the detection limit of the method. All calculations were checked for errors before data was accepted. The dataset contains measurements of the annual average abundance, biomass and elemental composition (C, N, P) of consumers (fish and invertebrates) in six rivers within sub-catchments of the Hampshire Avon of contrasting geology (clay, sand, chalk).