Characterization of Wind-Sea- and Swell-Induced Wave Energy along the Norwegian Coast

The necessity to reduce CO2 emissions in combination with the rising energy demand worldwide makes the extensive use of renewable energy sources increasingly important. To that end, countries with long coastlines, such as Norway, can exploit ocean wave energy to produce large amounts of power. In order to facilitate these efforts as well as to provide quantitative data on the wave energy potential of a specific area, it is essential to analyze the weather and climatic conditions detecting any variabilities. The complex physical processes and the atmosphere-wave synergetic effects make the investigation of temporal variability of wave energy a challenging issue. This work aims to shed new light on potential wave energy mapping, presenting a spatio-temporal assessment of swell- and wind-sea-induced energy flux in the Nordic Seas with a focus on the Norwegian coastline using the NORA10 hindcast for the period 1958–2017 (59 years). The results indicate high spatial and seasonal variability of the wave energy flux along the coast. The maximum wave energy flux is observed during winter, while the minimum is observed during summer. The highest coastal wave energy flux is observed in the Norwegian Sea. The majority of areas with dominant swell conditions (i.e., in the Norwegian Sea) are characterized by the highest coastal wave energy flux. The maximum values of wave energy flux in the North Sea are denoted in its northern parts in the intersection with the Norwegian Sea. In contrast to the Norwegian Sea, areas located in the North Sea and the Barents Sea show that wind sea is contributing more than swell to the total wave energy flux.publishedVersio

Gestational periodontitis impact on the fetus and neonate

Maternal oral pathologies during pregnancy represent a controversial subject. The incidence of periodontal disease is approximatively 40% among pregnant women. Periodontal disease has been associated with several unfortunate outcomes; among them, the most important are cardiovascular disorders, respiratory infections, diabetes and Alzheimer's disease. Regarding mechanisms, bacteria enter the blood stream and cross the placenta or the inflammatory mediators can affect the fetoplacental unit or generate an increased inflammatory response with subsequent consequences on the fetus. The most disputed subjects concerning periodontal disease in pregnancy are related to the effects on the pregnancy outcome and the offspring, respectively the associations between maternal periodontal disease and small for gestational age, preeclampsia, arteriosclerosis, gestational diabetes and perinatal mortality. In order to improve neonatal outcome and ensure maternal oral health, we should assure that the necessary dental treatment is provided during the entire pregnancy, preferably between 14 and 20 gestational weeks. Moreover, women should be encouraged to received dental treatment preconceptionally

Vitamin D supplementation – still a subject of debate

Vitamin D is a standard vitamin supplementation for children in many countries, used mainly for preventing rickets. Many studies were published about the efficiency of vitamin D administration in children and adults for other pathologies besides rickets. Very often the results were contradictory, but nevertheless, more and more articles are published on this matter. There is no consensus for the effective vitamin D dosage nor for the vitamin D normal serum values. Both vitamin D deficiency and vitamin intoxication are dangerous for children. Recently some studies are showing controversial data that advise being more careful in prescribing vitamin D as a routine

On the management of nature-based solutions in open-air laboratories: new insights and future perspectives

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Assessing Sea-State Effects on Sea-Salt Aerosol Modeling in the Lower Atmosphere Using Lidar and In-Situ Measurements

Atmospheric-chemical coupled models usually parameterize sea-salt aerosol (SSA) emissions using whitecap fraction estimated considering only wind speed and ignoring sea state. This approach may introduce inaccuracies in SSA simulation. This study aims to assess the impact of sea state on SSA modeling, applying a new parameterization for whitecap fraction estimation based on wave age, calculated by the ratio between wave phase velocity and wind speed. To this end, the new parameterization was incorporated in the coupled Chemical Hydrological Atmospheric Ocean wave modeling System (CHAOS). CHAOS encompasses the wave model (WAM) two-way coupled through the OASIS3-MCT coupler with the Advanced Weather Research and Forecasting model coupled with Chemistry (WRF-ARW-Chem) and, thus, enabling the concurrent simulation of SSAs, wind speed and wave phase velocity. The simulation results were evaluated against in-situ and lidar measurements at 2 stations in Greece (Finokalia on 4 and 15 July 2014 and Antikythera-PANGEA on 15 September 2018). The results reveal significant differences between the parameterizations with the new one offering a more realistic representation of SSA levels in some layers of the lower atmosphere. This is attributed to the enhancement of the bubble-bursting mechanism representation with air-sea processes controlling whitecap fraction. Our findings also highlight the contribution of fresh wind-generated waves to SSA modeling

Evaluating the Forecast Skill of a Hydrometeorological Modelling System in Greece

A hydrometeorological forecasting system has been operating at the Institute of Marine Biological Resources and Inland Waters (IMBRIW) of the Hellenic Centre for Marine Research (HCMR) since September 2015. The system consists of the Advanced Weather Research and Forecasting (WRF-ARW) model, the WRF-Hydro hydrological model, and the HEC-RAS hydraulic–hydrodynamic model. The system provides daily 120 h weather forecasts focusing on Greece (4 km horizontal resolution) and hydrological forecasts for the Spercheios and Evrotas rivers in Greece (100 m horizontal resolution), also providing flash flood inundation forecasts when needed (5 m horizontal resolution). The main aim of this study is to evaluate precipitation forecasts produced in a 4-year period (September 2015–August 2019) using measurements from meteorological stations across Greece. Water level forecasts for the Evrotas and Spercheios rivers were also evaluated using measurements from hydrological stations operated by the IMBRIW. Moreover, the forecast skill of the chained meteorological–hydrological–hydraulic operation of the system was investigated during a catastrophic flash flood in the Evrotas river. The results indicated that the system provided skillful precipitation and water level forecasts. The best evaluation results were yielded during rainy periods. They also demonstrated that timely flash flood forecasting products could benefit flood warning and emergency responses due to their efficiency and increased lead time

Four Decades of Surface Temperature, Precipitation, and Wind Speed Trends over Lakes of Greece

Climate change is known to affect world’s lakes in many ways. Lake warming is perhaps the most prominent impact of climate change but there is evidence that changes of precipitation and wind speed over the surface of the lakes may also have a significant effect on key limnological processes. With this study we explored the interannual trends of surface temperature, precipitation, and wind speed over 18 lakes of Greece using ERA5-Land data spanning over a period of almost four decades. We used generalized additive models (GAMs) to conduct time-series analysis in order to identify significant trends of change. Our results showed that surface temperature has significantly increased in all lakes with an average rate of change for annual temperature of 0.43 °C decade−1. With regard to precipitation, we identified significant trends for most lakes and particularly we found that precipitation decreased during the first two decades (1981–2000), but since 2000 it increased notably. Finally, wind speed did not show any significant change over the examined period with the exception for one lake. In summary, our work highlights the major climatic changes that have occurred in several freshwater bodies of Greece. Thus, it improves our understanding on how climate change may have impacted the ecology of these important ecosystems and may aid us to identify systems that are more vulnerable to future changes

Spatiotemporal variability of marine renewable energy resources in Norway

Marine Renewable Energy (MRE) resources such as wind and wave energy depend on the complex behaviour of weather and climatic conditions which determine the development of MRE technologies, energy grid, supply and prices. This study investigates the spatiotemporal variability of MRE resources along the Norwegian coast employing NORA10 (NOrwegian ReAnalysis 10 km) data for the period 1957-2016. The results indicate high local mean wind and wave energy resources exceeding 1 kW m-2 and 40 kW m-1, respectively. We find that MRE resources undergo a positive trend over time which is attributed to climatic variations of cyclonic distribution, frequency and intensity