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The seasonal and spatial dynamics of the key trophic characteristics were studied (food spectrum, feeding rate, and predatory impact on mesozooplankton) for populations of the jellyfish Aurelia aurita (Linnaeus, 1758) and ctenophore Mnemiopsis leidyi A. Agassiz, 1865. The investigation was carried out during four cruises of the RV “Professor Vodyanitsky” in the shelf areas of Crimean Peninsula in January to October 2016. The area was divided into inner (depth of < 50 m) and outer (51–150 m) shelves. To study the food spectrum and feeding rate of gelatinous predators, the composition of food items in the gastric cavity was analyzed under a binocular microscope. Daily ration (R, mg C·ind.−1·day−1) was calculated by the formula: R = Bz × DT−1 × 24, where Bz is zooplankton biomass in the predator gastric cavity (mg), and DT is zooplankton digestion time (h). Predatory impact of gelatinous zooplankton was estimated by the values of daily ration and mesozooplankton biomass. Zooplankton was sampled with a Juday plankton net with mouth diameter of 38 cm and mesh size of 140 µm. Vertical net hauls were performed: at the inner shelf stations, from the sea surface down to the bottom; at the outer shelf stations, down to the boundary of the hydrogen sulfide zone (δt = 16.2 conventional units according to a Sea-Bird probe). In the samples fixed with 4 % formalin solution, zooplankton abundance, its taxonomic composition, and size–age structure were quantified by standard method. In the food spectrum of the jellyfish, seasonal differences were revealed: predominance of Bivalvia veligers in winter and spring and wide species composition of Crustacea and other groups of prey in summer. The feeding rates of the studied species were similar: specific daily rations in winter, spring, and autumn did not exceed tenth of a percent of the carbon content in the body. Both species fed at a maximum rate in summer on the outer shelf: the specific rations reached 12.9 and 5.1 % C of the body for the jellyfish and ctenophore, respectively. A. aurita and M. leidyi populations consumed 0.2 to 5 % of the fodder zooplankton biomass per day; it did not result in a drastic reduction in zooplankton abundance and provided favorable feeding conditions for small planktivorous pelagic fish.

This document is a guideline for Monitoring of Macroplankton (Gelatinous plankton) in the Black Sea. It has been prepared in the frame of the EU/UNDP Project: Improving of Environmental Monitoring in the Black Sea – EMBLAS; Project Activity 3: Development of cost-effective and harmonized biological and chemical monitoring programmes in accordance with reporting obligations under multilateral environmental agreements, the WFD and the MSFD., This document has been prepared in the frame of the EU/UNDP Project: Improving of Environmental Monitoring in the Black Sea – EMBLAS. Publisher: Seredniak T.K., 18, PO Box 1212, Dnipro, 49018, Ukraine Certificate of registering the publishing entity in the State Register of Publishers, Manufacturers and Distributors of Publishing Products DK No. 4379 dated 02.08.2012. Publisher ID in the ISBN system 7953

The HITRAN database is a compilation of molecular spectroscopic parameters. It was established in the early 1970s and is used by various computer codes to predict and simulate the transmission and emission of light in gaseous media (with an emphasis on terrestrial and planetary atmospheres). The HITRAN com- pilation is composed of five major components: the line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, experimental infrared absorption cross-sections (for molecules where it is not yet feasible for representation in a line-by-line form), collision-induced absorption data, aerosol indices of refraction, and general tables (including partition sums) that apply globally to the data. This paper describes the contents of the 2020 quadrennial edition of HITRAN. The HITRAN2020 edition takes advantage of recent experimental and theoretical data that were meticulously validated, in particu- lar, against laboratory and atmospheric spectra. The new edition replaces the previous HITRAN edition of 2016 (including its updates during the intervening years). All five components of HITRAN have undergone major updates. In particular, the extent of the updates in the HITRAN2020 edition range from updating a few lines of specific molecules to complete replace- ments of the lists, and also the introduction of additional isotopologues and new (to HITRAN) molecules: SO, CH 3 F, GeH 4 , CS 2 , CH 3 I and NF 3 . Many new vibrational bands were added, extending the spectral cov- erage and completeness of the line lists. Also, the accuracy of the parameters for major atmospheric absorbers has been increased substantially, often featuring sub-percent uncertainties. Broadening param- eters associated with the ambient pressure of water vapor were introduced to HITRAN for the first time and are now available for several molecules. The HITRAN2020 edition continues to take advantage of the relational structure and efficient interface available at www.hitran.org and the HITRAN Application Programming Interface (HAPI). The functionality of both tools has been extended for the new edition.

The study reports the data on the distribution and predatory impact of the gelatinous macroplankton on mesozooplankton in the inshore waters of Crimea in April 2016. In the study areas, gelatinous macroplankton comprised Scyphomedusae Aurelia aurita (Linnaeus, 1758) and three ctenophore species (Mnemiopsis leidyi A. Agassiz, 1865, Beroe ovata Bruguire, 1789, and Pleurobrachia pileus (O. F. Müller, 1776). The biomass of A. aurita dominated everywhere and varied from ~ 62 to 330 g·m‑2 in different areas. The largest A. aurita biomass was observed in the South Coast of Crimea and the smallest in Karkinitsky Bay, where the number of jellyfish was high, suggesting the predominance of small individuals in the population. The size structure of A. aurita population differed by region: the proportion of large animals increased from the West to the East. The abundance and biomass of M. leidyi were rather low: 0.33–1.45 ind·m‑2 and 1–51.7 g·m‑2, respectively (the exception was the position in the Kerch Strait, where M. leidyi abundance reached 2 ind. m‑2 and biomass 126.3 g·m‑2); that species occurred only at 33–45 % of the stations (the exception was Karkinitsky Bay – 17 %), with the maximum values in the South Coast of Crimea. Large, 55–70-mm, adult individuals predominated. P. pileus biomass was lower than the biomass of A. aurita and M. leidyi in all areas, but its abundance was much higher. The daily rations of A. aurita varied widely both in the entire area and from one region to another. The daily ration values correlated with the carbon content in A. aurita body. The predation pressure of A. aurita on zooplankton in the inshore waters of Crimea was very low and did not result in a crucial decrease in mesozooplankton abundance. The effect of M. leidyi, even with its low abundance and biomass, was much stronger

The analysis of phytoplankton in the winter-spring period is important for investigating peculiarities of its annual dynamics and the Black Sea ecosystem overall functioning. Phytoplankton state in the winter-spring period in the Black Sea shelf zone is less studied than that of the summer-autumn season; conducting such a research is especially important for solving several problems, related to the productivity of the last links of the food chain, the formation of water hydrochemical regime, and the carbon cycle in the sea. The aim of the work is to assess the effect of seasonal conditions on the development of phytoplankton and its production estimates in the winter-spring period in the coastal waters of Crimea. The article presents the results of studies of hydrophysical (water temperature, density, and relative transparency) and biological indicators (chlorophyll a concentration, its fluorescence, taxonomic composition, and phytoplankton production estimates) in the Black Sea shelf zone in January – April 2016–2019. The studies were carried out at 50 stations, located in the coastal waters of Crimea from the Karkinitsky Bay to the Kerch Strait. Chlorophyll a concentration was measured by the standard fluorometric method, species composition was determined by microscopy, and phytoplankton specific growth rate was calculated according to the previously developed model. In winter (January – February), the values of chlorophyll a content and upper mixed layer depth were the highest (0.42–0.52 mg·m−3 and 44–58 m, respectively); in spring (March – April) they were 2–3 times lower. In January – February, the coccolithophore species Emiliania huxleyi (Lohmann) W. W. Hay & H. P. Mohler, 1967 predominated; in March – April, in different years, either dinoflagellates and diatoms or coccolithophores, dinoflagellates, and diatoms prevailed. In winter, chlorophyll a vertical distribution at most stations was uniform; in spring, unimodal profiles with a depth maximum prevailed, the location of which was not related to temperature and density gradients. Relative changes in chlorophyll a concentration and fluorescence with depth were usually the same. Phytoplankton production and daily production/biomass ratio (P/B) increased from winter to spring. There was no correlation between the values of integral production, biomass, and maximum specific growth rate of algae. Maximum specific growth rate was the least variable indicator. During the winter-spring period, algae in the photosynthetic zone divided on average once every 2–5 days.

Species composition, abundance, and distribution of gelatinous macroplankton in coastal and deep-sea areas of the Black Sea in November 2017 are discussed. Despite the fact that species composition of gelatinous macroplankton (medusa Aurelia aurita, ctenophores Mnemiopsis leidyi, Pleurobrachia pileus, and Beroe ovata) in 2017 did not differ from that in 2016, structural changes occured. In autumn 2017 A. aurita and B. ovata biomass was higher than in 2016 whereas the inverse difference was observed in their abundance values. Namely, A. aurita biomass was on average 514 g m-2 and 634 g m-2 in the outer shelf and deep-sea areas, respectively. Both parameters of M. leidyi and P. pileus declined in 2017 compared to the previous year. In addition, the share of large-sized individuals increased in 2017, while that of small-sized animals decreased, in comparison with 2016. The number of small individuals increased in P. pileus and decreased in M. leidyi, although their biomass before the seasonal appearance of B. ovata in plankton was close to that in 2016. The unprecedented increase in the medusae biomass in November 2017 could not be explained only by the competition with planktivorous ctenophores and may indicate alternative drivers controlling population dynamics of A. aurita in the Black Sea. A negative correlation was depicted between the Danube discharge in February-March and the rate of somatic growth of A. aurita.

With a view of achieving its obligations under the global climate change regime, and low technical potential for other renewable energy technologies, solar photovoltaics (PV) is the main focus for Singapore to generate low carbon electricity. However, a high penetration of PV in Singapore’s electricity market would result in a number of costs and benefits that need to be quantified in order to ensure prudent government policies for “supporting” the widespread adoption of PV in Singapore. The quantification of these costs and benefits would allow policymakers to realize the true “value” of solar PV for Singapore and would address the limitations of relying on the levelised cost of electricity metric. This paper provides an assessment of the societal value that PV would bring to Singapore, essentially an isolated power system with a liberalized electricity market. For the purpose of this study, the determination of the value of solar involves quantifying the savings due to the merit order effect, costs due to additional frequency control services, and net avoidance of CO2 emissions.

The seasonal and spatial dynamics of the main trophic characteristics (the food spectrum, the intensity of feeding and ingestion of mesozooplankton by the jellyfish Aurelia aurita (Linnaeus 1758) and ctenophore Mnemiopsis leidyi A. Agassiz 1865 populations were studied in four cruises of RV “Professor Vodyanitski” in the shelf regions of Crimean peninsula in January – Octobers 2016. The whole region was divided in inner (

This paper provides with the description, comparative analysis of multiple commonly used approaches of the analysis of system logs, and streaming data massively generated by company IT infrastructure with an unattended anomaly detection feature. An importance of the anomaly detection is dictated by the growing costs of system downtime due to the events that would have been predicted based on the log entries with the abnormal data reported. Anomaly detection systems are built using standard workflow of the data collection, parsing, information extraction and detection steps. Most of the document is related to the anomaly detection step and algorithms like regression, decision tree, SVM, clustering, principal components analysis, invariants mining and hierarchical temporal memory model. Model-based anomaly algorithms and hierarchical temporary memory algorithms were used to process HDFS, BGL and NAB datasets with ~16m log messages and 365k data points of the streaming data. The data was manually labeled to enable the training of the models and accuracy calculation. According to the results, supervised anomaly detection systems achieve high precision but require significant training effort, while HTM-based algorithm shows the highest detection precision with zero training. Detection of the abnormal system behavior plays an important role in large-scale incident management systems. Timely detection allows IT administrators to quickly identify issues and resolve them immediately. This approach reduces the system downtime dramatically.Most of the IT systems generate logs with the detailed information of the operations. Therefore, the logs become an ideal data source of the anomaly detection solutions. The volume of the logs makes it impossible to analyze them manually and requires automated approaches DOI: https://doi.org/10.17721/ISTS.2020.1.50-59

В прибрежной акватории Юго-Западного Крыма летом 2013 г. изучены видовой состав и количественные показатели мезо-, макро- и ихтиопланктона, а также питание личинок рыб. В ихтиопланктоне обнаружены икра и личинки 33 видов рыб из 24 семейств, что вдвое превысило показатели 1990-х гг. В мае 2013 г. в прибрежной акватории Севастополя наблюдался результативный нерест хамсы, которому способствовали благоприятная температура воды в море (+21 °C) и хорошие кормовые условия. Наибольшее количество летненерестующих видов зарегистрировано в июне при температуре поверхностной воды +22,7 °C. Численность икры рыб в 2013 г. увеличилась по сравнению с таковой в 2000 г. в 3,4 раза, личинок ― в 2,3 раза, что связано с их большей выживаемостью при улучшившихся условиях питания в результате относительно высокой численности зоопланктона с преобладанием мелкоразмерной фракции и доминированием в ней ювенильных стадий копепод. Другими факторами, улучшившими состояние кормовой базы личинок, были низкая численность гребневика Mnemiopsis leidyi A. Agassiz, 1865 и его слабое воздействие

We report the results of the trajectory-based simulation of far-infrared collision-induced absorption (CIA) due to CH$_4-$N$_2$ pairs at temperatures between 70 and 400 K. Our analysis utilizes recently calculated high-level potential energy (PES) and induced dipole surfaces (IDS) [Finenko, A. A., Chistikov, D. N., Kalugina, Y. N., Conway E. K., Gordon, I. E., Phys. Chem. Chem. Phys., 2021, doi: 10.1039/d1cp02161c]. Treating collision partners as rigid rotors, the time evolution of interaction-induced dipole is accumulated over a vast ensemble of classical trajectories and subsequently transformed into CIA spectrum via Fourier transform. In our calculations, both bound and unbound states are properly accounted for, and the rigorous theory of lower-order spectral moments is addressed to check the accuracy of simulated profiles. Classically derived trajectory-based profiles are subject to two approximate desymmetrization procedures so that resulting profiles conform to the quantum principle of detailed balance. The simulated profiles are compared to laboratory measurements and employed for modeling Titan's spectra in the 50-500 cm$^{-1}$ range. Based on the desymmetrized simulated profiles, a new semi-empirical model for CH$_4-$N$_2$ CIA is proposed for modeling Titan's infrared spectra. Synthetic spectra derived using this model yield an excellent agreement with the data recorded by the Composite Infrared Spectrometer (CIRS) aboard the Cassini spacecraft at low and high emission angles.

The analysis of phytoplankton in the winter-spring period is important for investigating peculiarities of its annual dynamics and the Black Sea ecosystem overall functioning. Phytoplankton state in the winter-spring period in the Black Sea shelf zone is less studied than that of the summer-autumn season; conducting such a research is especially important for solving several problems, related to the productivity of the last links of the food chain, the formation of water hydrochemical regime, and the carbon cycle in the sea. The aim of the work is to assess the effect of seasonal conditions on the development of phytoplankton and its production estimates in the winter-spring period in the coastal waters of Crimea. The article presents the results of studies of hydrophysical (water temperature, density, and relative transparency) and biological indicators (chlorophyll a concentration, its fluorescence, taxonomic composition, and phytoplankton production estimates) in the Black Sea shelf zone in January – April 2016–2019. The studies were carried out at 50 stations, located in the coastal waters of Crimea from the Karkinitsky Bay to the Kerch Strait. Chlorophyll a concentration was measured by the standard fluorometric method, species composition was determined by microscopy, and phytoplankton specific growth rate was calculated according to the previously developed model. In winter (January – February), the values of chlorophyll a content and upper mixed layer depth were the highest (0.42–0.52 mg·m−3 and 44–58 m, respectively); in spring (March – April) they were 2–3 times lower. In January – February, the coccolithophore species Emiliania huxleyi (Lohmann) W. W. Hay & H. P. Mohler, 1967 predominated; in March – April, in different years, either dinoflagellates and diatoms or coccolithophores, dinoflagellates, and diatoms prevailed. In winter, chlorophyll a vertical distribution at most stations was uniform; in spring, unimodal profiles with a depth maximum prevailed, the location of which was not related to temperature and density gradients. Relative changes in chlorophyll a concentration and fluorescence with depth were usually the same. Phytoplankton production and daily production/biomass ratio (P/B) increased from winter to spring. There was no correlation between the values of integral production, biomass, and maximum specific growth rate of algae. Maximum specific growth rate was the least variable indicator. During the winter-spring period, algae in the photosynthetic zone divided on average once every 2–5 days.

We present an extensive study of the five-dimensional potential energy and induced dipole surfaces of the CH4–N2 complex assuming rigid-rotor approximation. Within the supermolecular approach, ab initio calculations of the interaction energies and dipoles were carried out at the CCSD(T)-F12 and CCSD(T) levels of theory using the correlation-consistent aug-cc-pVTZ basis set, respectively. Both potential energy and induced dipole surfaces inherit the symmetry of the molecular system and transform under the A1+ and A2+ irreducible representations of the molecular symmetry group G48, respectively. One can take advantage of the symmetry when fitting the surfaces; first, when constructing angular basis functions and second, when selecting the grid points. The approach to the construction of scalar and vectorial basis functions exploiting the eigenfunction method [Q. Chen, J. Ping and F. Wang, Group Representation Theory for Physicists, World Scientific, 2nd edn, 2002] is developed. We explore the use of Sobolev-type quadrature grids as building blocks of robust quadrature rules adapted to the symmetry of the molecular system. Temperature variations of the cross second virial coefficient and first classical spectral moments of the rototranslational collision-induced band were derived. A reasonable agreement between calculated values and experimental data was found attesting to the high quality of constructed surfaces.

This paper presents further development of the new semi-classical trajectory-based formalism described in Paper I [Chistikov et al., J. Chem. Phys. 151, 194106 (2019)]. We report the results of simulation and analysis of the low-frequency collision-induced absorption (CIA) in CO2–Ar, including its true dimer component. Our consideration relies on the use of ab initio intermolecular potential energy and induced dipole surfaces for CO2–Ar calculated in an assumption of a rigid CO2 structure using the CCSD(T) method. The theory, the details of which are reported in Paper I [Chistikov et al., J. Chem. Phys. 151, 194106 (2019)], permits taking into account the effect of unbound and quasi-bound classical trajectories on the CIA in the range of a rototranslational band. This theory is largely extended by trajectory-based simulation of the true bound dimer absorption in the present paper. The spectra are obtained from a statistical average over a vast ensemble of classical trajectories restricted by properly chosen domains in the phase space. Rigorous classical theory is developed for two low-order spectral moments interpreted as the Boltzmann-weighted average of the respective dipole functions. These spectral moments were then used to check the accuracy of our trajectory-based spectra, for which both spectral moments can be evaluated independently in terms of specific integrals over the trajectory-based calculated spectral profiles. Good agreement between the spectral moments calculated as integrals over the frequency domain or the phase space largely supports the reliability of our simulated CIA spectra, which conform with the available microwave and far-infrared observations.

The gelatinous macroplankton community of the Black Sea renews annually and functionates differently depending on the complicated system of trophic relations and interannual fluctuations of biotic and abiotic factors. Its monitoring is necessary for the evaluation of the current state and possible vectors of evolution of the whole pelagic ecosystem. For this purpose the data on the composition and distribution of gelatinous organisms were collected on the 89th cruise of the RV “Professor Vodyanitsky” (September – October of 2016) at 62 stations located in coastal areas and in the open sea to the south and southwest of Crimea. Samples were taken with the Bogorov – Rass net (inlet area of 0.5 m², mesh of 300 µm) using vertical net hauls from the bottom to the sea surface in the shallow shelf and from the lower boundary of the oxygen zone [according to the dissolved oxygen sensor CTD SBE plus (Sea Bird)] to the sea surface – in deepwater areas. Aurelia aurita and 3 ctenophore species (Mnemiopsis leidyi, Pleurobrachia pileus, and Beroe ovata) were present together in the 90 % of the samples (on 56 stations). In spite of some increase in average biomass of every species in deep sea areas, and, particularly, of A. aurita up to 260 g per m², there was no difference between the data of 2016 and 2010 (p > 0.05). The abundance of A. aurita increased by about one order of magnitude (p < 0.001); the abundance of P. pileus increased 2–5 times (p < 0.001); of B. ovata – 3–15 times (p < 0.01). M. leidyi abundance increased only at the outer Black Sea shelf; in other regions it could have been restricted by B. ovata predation. A. aurita linear specific growth rate in 2016 was one of the lowest for the last 15 years. Slow somatic growth of the jellyfish indicates unfavorable conditions for this species in 2016. However, the jellyfish biomass was higher than that of previous years because of the huge abundance of the spring generation. The weakening competition with planktivorous ctenophores may lead to even greater increase in the ecological valence of A. aurita among other gelatinous predators in the nearest future.

The existence of two alternative points of view on the long-term dynamics of gelatinous macroplankton populations in the World Ocean determines the need for long-term monitoring as a basis for assessing their condition. The accumulation of long-term series of data on the development of gelatinous predators in the Black Sea makes it possible to assess their role in the functioning of the pelagic ecosystem in connection with climatic variability. The abundance, biomass, the size structure of the gelatinous predators (jellyfish Aurelia aurita; ctenophores Mnemiopsis leidyi and Pleurobrachia pileus) and the feeding intensity of the two species (A. aurita and M. leidyi) were investigated in the early summer period (June) of 2016 at 45 stations covering the shelf zone off the coast of Crimea from Cape Tarkhankut to Kerch, as well as at 3 stations of the deepwater area with the coordinates 44°23′N–45°5′N and 32°22′E–36°36′E. The material was collected from the bottom (10–100 m) up to the surface at the inshore stations and from the depth with σt = 16.2 to the surface – in deepwater by vertical trawls with modified Bogorov – Russ net with an inlet diameter of 80 cm, a mesh of 300 μm. The nutritional spectrum and its quantitative composition were determined under a microscope in the laboratory immediately after the catch of animals, followed by the calculation of diurnal rations and the rate of ingestion of zooplankton. Spatial differences in abundance of gelatinous species were observed: the maximum biomass of A. aurita, prevailing in all regions, was observed in the Yevpatoriya – Sevastopol region and was due to large accumulations of middle-sized specimens of new generation. Ctenophora P. pileus dominated in the abundance in the halistatic zone. The food spectrum of jellyfish was very diverse and included various stages of Copepoda, Tunicata, Cladocera, and also the meroplankton – the Bivalvia and Gastropoda veligers. The halistatic zone with great depths was characterized by the widest species composition of planktonic Copepoda in A. aurita food. The average daily rations of jellyfish varied from one region to another, being the lowest in the Karkinitsky Bay [(0.113 ± 0.10) mg C-1·day-1, or (1.6 ± 2.18) % of C body] with most of the food being algae C. granii. The most intensive feeding was in the halistatic zone [(56.2 ± 23.7) % of C body] with a predominance of Calanus euxinus and Pseudocalanus elongatus in the diet. In no region A. aurita can compensate the respiration requirements by the consumption of mesozooplankton. The highest impact on zooplankton was provided by jellyfish population in the Karkinitsky Bay and in the Yevpatoriya – Sevastopol region, although along all the shelf its impact was very low and did not lead to a dramatic reduction in the zooplankton community abundance.

Species composition and quantitative indicators of zoo- and ichthyoplankton feeding of fish larvae were studied inshore of the South-Western Crimea in the summer of 2013. There were 33 species of fish eggs and larvae from 24 families identified in ichthyoplankton. It was twice as large as it was in the 1990s. Inshore of Sevastopol in May 2013 the anchovy spawning was efficiently spawned due to favorable temperature of the sea water (+21 °C) and good food conditions. The largest number of summer-spawning species was recorded in June at the surface water temperature of +22.7 °C. Abundance of fish larvae in inshore region increased too, compared to this of the 2000s, due to their high survival rate resulting from improved food conditions. There was relatively high abundance of zooplankton and the predominance of a small-sized fraction mainly by juvenile stages of copepods. Low abundance of ctenophore Mnemiopsis leidyi and its slight impact on zooplankton were other factors that improved the food base of fish larvae.

The use of satellite data to study the chlorophyll a dynamics, in contrast to contact methods, allows carrying out large scale research with high frequency of measurements. Such observations were carried out in the Black Sea offshore and inshore areas from 1998 to 2015. They made it possible to estimate the annual and interannual chlorophyll a dynamics in the surface layer and to reveal the periodicity, intensity, and duration of mass development of algae. In the western and eastern cyclonic gyres as well as in the shelf zone off the Crimean and Caucasus coasts, annual chlorophyll dynamics had the same pattern as that repeating year after year. From August-September to April-May of the next year the variation of chlorophyll in most cases corresponded to normal distribution and had a form of a bell-shaped curve with maximum observed in December-January. During autumn period, the chlorophyll concentration gradually increased with water cooling and seasonal pycnoclyne weakening. In winter the chlorophyll concentration decreased due to increase of mixed layer depth. Spring phytoplankton intensive development was observed every year when convective mixing weakened and stability of water column increased.

Small island developing states (SIDS) have some of the highest electricity tariffs globally. Renewable energy (RE) technologies could thus have reached grid parity in various SIDS. Furthermore, the abundance of resources such as solar and wind provides ample potential for SIDS to switch from high cost diesel generators to renewables. Despite favourable conditions, RE remains a largely underinvested sector in these regions. This paper aims to undercover the reasons why grid parity does not necessary translate into private sector investments in RE. With a focus on SIDS, this paper presents an evidence that achieving grid parity based on LCOE estimates is an incomplete benchmark for decision making in the power generation industry. In particular, LCOE and grid parity do not take into account financing constraints of RE projects which are often more pronounced compared to conventional forms of power generation. This paper thus presents the business perspective of RE projects, by employing a discounted cashflow model that includes various profitability metrics and effects of taxation and depreciation. The study shows that financing conditions exert strong influence on the economic feasibility of solar projects, both in LCOE terms and profitability terms. Thus, key policies should be targeted at improving financing conditions to ensure mobilization of private sector finances in solar PV.

Studying temporal patterns in emissions associated with electricity generation is increasingly important. On the supply side, there is interest in integrating renewable energy sources (solar, wind), which are known to vary daily and hourly. On the demand side, the concept of demand response is driving a need to better understand the impact of peak versus off-peak loading, with the objective of maximizing efficiency. In this study, we examine the case of electric power generation in Singapore, and aim to assess the half-hourly variation in associated average carbon dioxide emissions. Given the country’s serious push for clean energy solutions and a possibility of adopting carbon trading in the future, we feel the need to address the currently existing gap in research on daily CO 2 emissions patterns. By associating representative electricity generation data with the characterized fleet of power plants, half-hourly emissions are found to range between 415 and 455 kg CO 2 per MW h. Marginal emission factors show a fluctuating daily pattern between 390 and 800 kg CO 2 /MW h. Policy makers able to work with real generation data can use this approach to understand the carbon footprint of short-term supply and demand interventions.

The steady rise in energy demand is expected to continue in Singapore due to the country's economic and population growth. According to projections, electricity generation will increase by some 30% from 2010 to 2025. Despite the rise in demand, Singapore authorities have announced a commitment to reduce carbon emissions by 7-11% below 2020 business-as-usual levels, with a half of reductions coming from the power generation sector. In this study, we examine the average carbon dioxide (CO 2 ) emissions or grid factor of power generation in Singapore, and aim to assess the carbon emissions reduction potential arising from different fuel and generation technology mixes. Adding alternative feedstocks and/or displacing existing generation technologies can have a wide range of consequences on the theoretical grid factor. We show that emissions savings can vary substantially depending on the type of fuel sources that are either added to the mix, or used to displace existing generation feedstocks. The results highlighted in this study provide a Singapore-specific example for targeting medium to longer-term emission savings from the power generation sector.

Gelatinous predators are the most important components of the Black Sea ecosystem. In spite of the numerous studies of different aspects of their biology (horizontal and vertical distribution, bioenergetical indices of the growth and energy transformation on organism and population levels) data on population conditions and their functioning in winter period is very scarce. In present study data on numerical abundance, biomass, size structure of jellyfish predators (Aurelia aurita, Mnemiopsis leidyi, Beroe ovata и Pleurobrachia pileus) and feeding intensity of two dominated species (A. aurita, M. leidyi) were investigated on 17 stations in inshore waters near Crimea in winter 2016. Sampling was carried out with the modified Bogorov – Rass net with 80 cm diameter, mesh 300 mkm by vertical tows from the bottom to the surface (0–100 m). Biomass of A. aurita varied from 30 to 1990 g·m-2 with higher values in the southern region. Other species biomass was much lower (maximum values are 170 g·m-2 of M. leidyi and 60 g·m -2 of P. pileus). High biomass of B. ovata (85 g·m-2), comparable with the summer values, was observed at a station in the northern shelf. A significant difference in biomass of the species between the regions was not revealed except a difference in B. ovata biomass in the northern and southern regions (p < 0.05). The bulk of all species populations were formed by adult individuals. The Bivalvia veligers were the main food items in A. aurita and different Copepoda stages – in M. leidyi. Daily rations in A. aurita were 0.009–0.107, in M. leidyi – 0.02–0.28 % C body and were much lower of jellyfish food requirements at that temperature conditions.

The impact of the invasive ctenophore Mnemiopsis leidyi on the zooplankton commu- nity of the Caspian Sea was quantified according to food consumption and other major physiological activities (i.e. respiration and reproduction), coupled with field data on population structure. The adverse effects of M. leidyi on the zooplankton community during the first years of the invasion were tremendous for the Caspian Sea compared to other regions affected by this ctenophore. The impact was highest in summer, due to high water temperatures and a population size structure in which juvenile ctenophores with mean lengths of 2 to 5 mm accounted for most of the population. During winter/spring, these ctenophores could consume the available stock of zooplankton in 3 to 8 d, whereas in summer consumption took only 1 d. The computed critical ctenophore biomass that does not affect (decrease) the abundance of mesozooplankton in the Caspian Sea is about 4 g m -3 (or 120 g m -2 , assuming most of the ctenophores occur in the upper 30 m layer). As is clear from the moni- toring data, the M.leidyi biomass in summer in different regions of the Caspian Sea is far in excess of this value. Such a high abundance of ctenophores, if maintained, would constantly keep the non- gelatinous zooplankton biomass at very low levels, and, as a consequence, no recovery could be expected in the pelagic fishery.