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Herewith we present the extended 1Hz dataset of wind measurements from a Skipheia meteorological station on the island of Frøya on the western coast of Norway, Trondelag. The data binned in 10 min averages can be find at: https://doi.org/10.5281/zenodo.2557500 The site represents an exposed coastal wind climate with open sea, land and mixed fetch from various directions. UTM-coordinates of the Met-mast: 8.34251 E and 63.66638 N. See the map for details (NorwegianMapping Authority): https://www.norgeskart.no/#!?project=norgeskart&layers=1003&zoom=3&lat=7035885.49&lon=539601.41&markerLat=7077031.483032227&markerLon=170902.83203125&panel=searchOptionsPanel&sok=Titranveien Presented data were gathered between years 2009-2016. Data&hardware summary: Years 2009-2016: Mast2 equipped with 6 pairs of 2D sonic anemometers at 10, 16, 25, 40, 70, 100 m above the ground, independent temperature measurements at the same heights and near the ground; pressure and relative humidity from local meteostation (Sula, 20 km away). Years 2014-2016: Mast4 equipped with 2 pairs of 2D sonic anemometers at 40 and 100 m above the ground. The distance between the masts is 79 m. Data is binned in years and months and stored in a ‘*.txt’ tab-separated values file. Data column order is described in SkipheiaMast2_header.txt and SkipheiaMast4_header.txt, where WSx is the wind speed (m/s), WDx is the wind direction (360 deg), ATx is the air temperature (deg C) and x designates the instrument number. The instruments are numbered starting from the ground. Example: For Mast2 (6 pairs of anemometers, ground temperature + 6 temperature sensors on the mast) that means that AT0 is the ground temperature. WS1 and WS2 are wind speed records at 10 m level. WS3 and WS4 are wind speed records at 16 m. For Mast4 (2 pairs of anemometers) that means that WS1 and WS2 are wind speed records at 40 m level. WS3 and WS4 are wind speed records at 100 m. Detailed site description with wind climate description can be found in attached analysis: Site analysys.pdf. Additional information and analysis can be found in listed below works, using data from Frøya site: Bardal, L. M., & Sætran, L. R. (2016, September). Spatial correlation of atmospheric wind at scales relevant for large scale wind turbines. In Journal of Physics: Conference Series (Vol. 753, No. 3, p. 032033). IOP Publishing, doi:10.1088/1742-6596/753/3/032033, https://iopscience.iop.org/article/10.1088/1742-6596/753/3/032033/pdf Bardal, L. M., & Sætran, L. R. (2016). Wind gust factors in a coastal wind climate. Energy Procedia, 94, 417-424, https://doi.org/10.1016/j.egypro.2016.09.207 IEA Wind TCP Task 27 Compendium of IEA Wind TCP Task 27 Case Studies, Technical Report, Prepared by Ignacio Cruz Cruz, CIEMAT, Spain Trudy Forsyth, WAT, United States, October 2018; Chapter 1.8. https://community.ieawind.org/HigherLogic/System/DownloadDocumentFile.ashx?DocumentFileKey=8afc06ec-bb68-0be8-8481-6622e9e95ae7&forceDialog=0 Domagalski, P., Bardal, L. M., & Sætran, L. Vertical Wind Profiles in Non-neutral Conditions-Comparison of Models and Measurements from Froya. Journal of Offshore Mechanics and Arctic Engineering, doi: 10.1115/1.4041816, http://offshoremechanics.asmedigitalcollection.asme.org/article.aspx?articleid=2711333&resultClick=3 Møller, M., Domagalski, P., & Sætran, L. R. (2019, October). Characteristics of abnormal vertical wind profiles at a coastal site. In Journal of Physics: Conference Series (Vol. 1356, No. 1, p. 012030). IOP Publishing. https://iopscience.iop.org/article/10.1088/1742-6596/1356/1/012030 Møller, M., Domagalski, P., and Sætran, L. R.: Comparing Abnormalities in Onshore and Offshore Vertical Wind Profiles, Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2019-40 , in review, 2019.

A priority of the industrial applications of microalgae is the reduction of production costs while maximizing algae biomass productivity. The purpose of this study was to carry out a comprehensive evaluation of the effects of pH control on the production of Nannochloropsis gaditana in tubular photobioreactors under external conditions while considering the environmental, biological, and operational parameters of the process. Experiments were carried out in 3.0 m3 tubular photobioreactors under outdoor conditions. The pH values evaluated were 6.0, 7.0, 8.0, 9.0, and 10.0, which were controlled by injecting pure CO2 on-demand. The results have shown that the ideal pH for microalgal growth was 8.0, with higher values of biomass productivity (Pb) (0.16 g L-1 d-1), and CO2 use efficiency ([Formula: see text]) (74.6% w w-1); [Formula: see text]/biomass value obtained at this pH (2.42 [Formula: see text] gbiomass-1) was close to the theoretical value, indicating an adequate CO2 supply. At this pH, the system was more stable and required a lower number of CO2 injections than the other treatments. At pH 6.0, there was a decrease in the Pb and [Formula: see text]; cultures at pH 10.0 exhibited a lower Pb and photosynthetic efficiency as well. These results imply that controlling the pH at an optimum value allows higher CO2 conversions in biomass to be achieved and contributes to the reduction in costs of the microalgae production process.

Abstract A high-order Discontinuous Galerkin (DG) finite element time-stepping method is applied for the numerical solution of optimal control problems within the framework of Pontryagin’s Maximum Principle. The method constitutes an efficient and versatile alternative to the well-known Pseudospectral (PS) methods. The two main advantages of DG in comparison with the PS methods are: the local nature of the piecewise polynomial solution and the straightforward implementation of element-wise mesh and polynomial refinement if required. Two types of non-linear optimal control problems were analysed: continuous and bang–bang time-solutions. In the case of bang–bang optimal control problems, an h -refinement strategy was developed to achieve agreement between the observed and the formal order of accuracy. The paper also deals with sub-optimal control problems where: (i) time-step is fixed and non-infinitesimal; (ii) the control has two modes (on/off); (iii) the control command is only applied at the beginning of each time-step; and iv) the number of switching instants is large and not known a priori .

To identify some of the possible environmental factors stimulating the increasingly frequent outbreaks of the scyphomedusa Pelagia noctiluca in the Straits of Messina, we investigated its abundance, growth, reproduction and feeding over a 4-year period, from 2007 to 2011, at two coastal sites. Using either field investigations and manipulative experiments we show that, among the various factors considered, shifts in water temperature (influencing medusae metabolism, growth and reproduction rates) and the size structure of the zooplankton community (their natural preys) can promote the proliferation of P. noctiluca. In particular, we show that increased temperature let jellyfishes to grow more rapidly and reach exceptional sizes. We also report a peculiar opportunistic behavior of P. noctiluca, which makes this species a potentially strong competitor in the pelagic trophic web of the Straits ecosystem. We therefore propose that more frequent P. noctiluca outbreaks stimulated by increasing sea surface temperature and shifts in their prey availability and composition would become, in the near future, a major cause of ecosystem shift.

We document a remarkable abundance of the tubeworm Serpula vermicularis Linnaeus, 1767, in bathyal coral habitats from the Bari Canyon System in the southern Adriatic Sea. Here, the specimens of S. vermicularis grow from muddy substrate either as isolated individuals or as localized clusters of multiple individuals. Peculiar tube aggregations are also associated with Madrepora oculata build-ups and other stony corals including Desmophyllum dianthus. Three types of coral-serpulid (C–S) frameworks have been recognized based upon size and shape. The abundance of S. vermicularis increases with the size of C–S frameworks, which results from superimposition, overgrowth, and/or intergrowth of scleractinians and serpulids. Several generations of S. vermicularis contribute to the C–S frameworks, each most probably accounting for more than 8 years and presumably existing in the area for the last hundreds of years. At a meso-scale, the distribution pattern of serpulids seems to be mainly governed by currents and siltation. A further constraint is the co-occurring solitary coral D. dianthus within frameworks. The successful sea-bottom colonization by S. vermicularis and associated C–S frameworks is possibly related to a high oxygen content and food supply derived from the North Adriatic Dense Water (NAdDW). The flourishing populations of S. vermicularis as well as the peculiarity of C–S frameworks suggest that deep-sea canyons provide important benthic habitats in bathyal environments.

As a consequence of increasing atmospheric CO(2), the world's oceans are warming and slowly becoming more acidic (ocean acidification, OA) and profound changes in marine ecosystems are certain. Calcification is one of the primary targets for studies of the impact of CO(2)-driven climate change in the oceans and one of the key marine groups most likely to be impacted by predicted climate change events are the echinoderms. Echinoderms are a vital component of the marine environment with representatives in virtually every ecosystem, where they are often keystone ecosystem engineers. This paper reviews and analyses what is known about the impact of near-future ocean acidification on echinoderms. A global analysis of the literature reveals that echinoderms are surprisingly robust to OA and that important differences in sensitivity to OA are observed between populations and species. However, this is modulated by parameters such as (1) exposure time with rare longer term experiments revealing negative impacts that are hidden in short or midterm ones; (2) bottlenecks in physiological processes and life-cycle such as stage-specific developmental phenomena that may drive the whole species responses; (3) ecological feedback transforming small scale sub lethal effects into important negative effects on fitness. We hypothesize that populations/species naturally exposed to variable environmental pH conditions may be pre-adapted to future OA highlighting the importance to understand and monitor environmental variations in order to be able to to predict sensitivity to future climate changes. More stress ecology research is needed at the frontier between ecotoxicology and ecology, going beyond standardized tests using model species in order to address multiple water quality factors (e.g. pH, temperature, toxicants) and organism health. However, available data allow us to conclude that near-future OA will have negative impact on echinoderm taxa with likely significant consequences at the ecosystem level.

In spite of considerable progress in our understanding of ecosystem functioning, our ability to design effective and enforceable environmental policies requires a deep understanding of human perceptions and beliefs. In this respect, what is called today stakeholder analysis is an eclectic mixture of qualitative and semi-quantitative techniques aiming at eliciting, understanding and de-codifying how individuals perceive risks and threats towards sustainability. Fuzzy Cognitive Mapping (FCM) is gradually emerging as an alternative methodology capable of assisting researchers in the domain of environmental policy. We explored the promise that FCM holds to support environmental policy makers. We suggest FCM approach as a new participatory method in environmental policy: through aiding in Multi-stakeholder (actor) analysis for risk assessment, capturing values and scenarios construction. To show how this is feasible we try to answer three basic questions: How cognitive mapping can support decision-making? How FCM can support environmental decision-making? How simulation of concepts may help in communicating stakeholders' views to environmental decision makers? Then we explore the potential application of FCM in environmental policy, especially in environmental economics, trying to substantiate economic values for nature providing 'flesh and bones' to the concept of economic preferences.

Globally, the spread of non-indigenous species in marine ecosystems is a major ecological and socio-economical concern. The need for long-term assessment on a large scale is a pre-requisite for understanding the drivers associated with their establishment and expansion. Here, the patterns of invasions of subtidal soft-bottom assemblages of shelled molluscs have been quantified based on a unique dataset collected between 2005 and 2012 along the coast of Israel (SE Mediterranean Sea), a hotspot of bioinvasion. Overall, the number of non-indigenous species doubled between 2005 and 2012. Significant differences in terms of species richness and relative abundance were observed in space and time in both native and non-indigenous species. A combination of enduring disturbance regimes related to human activities and site-specific environmental conditions seem to have a critical role in promoting the observed patterns. Our results emphasize the value of long term broad-scale systematic surveys to the development of effective environmental policies for the control of bioinvasions.

AbstractChanges in climate, in combination with intensive exploitation of marine resources, have caused large‐scale reorganizations in many of the world's marine ecosystems during the past decades. The Baltic Sea in Northern Europe is one of the systems most affected. In addition to being exposed to persistent eutrophication, intensive fishing, and one of the world's fastest rates of warming in the last two decades of the 20th century, accelerated climate change including atmospheric warming and changes in precipitation is projected for this region during the 21st century. Here, we used a new multimodel approach to project how the interaction of climate, nutrient loads, and cod fishing may affect the future of the open Central Baltic Sea food web. Regionally downscaled global climate scenarios were, in combination with three nutrient load scenarios, used to drive an ensemble of three regional biogeochemical models (BGMs). An Ecopath with Ecosim food web model was then forced with the BGM results from different nutrient‐climate scenarios in combination with two different cod fishing scenarios. The results showed that regional management is likely to play a major role in determining the future of the Baltic Sea ecosystem. By the end of the 21st century, for example, the combination of intensive cod fishing and high nutrient loads projected a strongly eutrophicated and sprat‐dominated ecosystem, whereas low cod fishing in combination with low nutrient loads resulted in a cod‐dominated ecosystem with eutrophication levels close to present. Also, nonlinearities were observed in the sensitivity of different trophic groups to nutrient loads or fishing depending on the combination of the two. Finally, many climate variables and species biomasses were projected to levels unseen in the past. Hence, the risk for ecological surprises needs to be addressed, particularly when the results are discussed in the ecosystem‐based management context.