Light Winds Research Articles

Modulation effect of linear shear flow, wind, and dissipation on freak wave generation in finite water depth

This paper studies the modulation effect of linear shear flow (LSF), comprising a uniform flow and a shear flow with constant vorticity, combined with wind and dissipation on freak wave generation in water of finite depth. A nonlinear Schrödinger equation (NLSE) modified by LSF, strong wind, and dissipation is derived. This can be reduced to consider the effects of LSF, light wind, and dissipation, and further reduced to include only LSF. The relation between modulational instability (MI) of the NLSE and freak waves represented as a modified Peregrine Breather solution is analyzed. When considering only LSF, the convergence (divergence) effect of uniform up-flow (down-flow) and positive (negative) vorticity increases (decreases) the MI growth rate and promotes (inhibits) freak wave generation. The combined effect of LSF and light wind shows that a light adverse (tail) wind can restrain (amplify) MI and bury (trigger) freak waves. Under the effect of a light tailwind, LSF has the same effect on the MI growth rate and freak wave generation as the case without any wind. The combination of LSF and strong wind enables both adverse and tail winds to amplify MI and trigger freak waves. In the presence of strong wind, LSF has the opposite effect to the case of a light tailwind.

Stability of the Vertical Distribution of Dust Aerosol in Light and Moderate Winds

The profiles of dust aerosol mass concentration obtained with multilevel (0.2, 0.4, 0.8, 1.6, and 3.2 m) daytime measurements in arid conditions in 2020–2022 show a power dependence on height. We distinguish three main types of changes in concentration with height: a) in low wind (degrees are close to –0.5); b) spike changes in concentration when wind increases (degrees reach and exceed –1); c) inversions (concentration increases with height at two or three lower levels of measurements): weak – about –20 mkg/cm3, significant – more than 50 mkg/cm3. The power dependence of –0.5 is explained by the collective effect of the rise of the ensemble of closely located bubbles of air warmed around the dust particles. In weak and moderate winds, this mode is more common. Burst changes in concentration are associated with the emergence of turbulent structures.

The urge to breed early: Similar responses to environmental conditions in short‐ and long‐distance migrants during spring migration

AbstractBirds migrating different distances experience different temporal, energetic, physiological, and physical constraints throughout migration, which is reflected in their migration strategy. Consequently, we predict different behavioral decisions to similar environmental cues between short‐ and long‐distance migrants, which has been documented for autumn migration. Here, we focus on the question whether trade‐off decisions regarding departure, routing, and landing when alternating between migratory endurance flights and stopovers also differ during spring migration. As early arrivals at the breeding grounds should be ultimately favored regardless of migration distance, selection may favor more similar behavioral decisions in spring than in autumn. We radio‐tagged short‐ and long‐distance migratory songbirds at stopover sites along the German North Sea coast during spring and automatically tracked their migratory behavior using a large‐scale network of receiver stations. Once departed, birds could either cross the sea or detour along the coast. We corrected for spatially biased detection data, using a hierarchical multistate model to assess how birds respond to variation in environmental conditions in their day‐to‐day departure decisions and route selection. The day‐to‐day departure probability was higher in long‐distance migrants independently of the routing decision. Irrespective of migration distance, all species more likely departed under light winds and rainless conditions, while the influence of air pressure change and relative humidity was species‐specific. By accounting for detection probabilities, we estimated that about half of all individuals of each species crossed the sea but did not find differences between short‐ and long‐distance migrants. Offshore flights were more likely when winds blew offshore and began earlier within the night compared with onshore flights. Our results suggest that selection more similarly affects birds of different migration distances in spring than in autumn. These findings put the focus toward how ultimate mechanisms may shape departure and routing decisions differently between migration seasons.

Scalable, Green, and Cost-Effective Carbonized Sand for Efficient Solar Desalination.

Nowadays, sweet and drinkable water shortage is a global issue which has attracted widespread attention. Desalination of seawater as the greatest source of water on our planet using solar energy as the most abundant and green energy source for producing fresh water can help us address this issue. Interfacial solar desalination is a state-of-the-art, sustainable, green, and energy-efficient method that has been studied lately. One of the key parameters for researching this method with reasonable efficiency is a photothermal material. Herein, carbon-coated sand was synthesized using abundant, green, and low-cost materials (sand and sugar), and its performance as a photothermal material is investigated and reported. In this work, a three-dimensional (3D) system is introduced to develop the performance and efficiency of the system under real sun irradiation and natural circumstances. The salt rejection ability of the system is another important thing we should notice due to the high salinity of seawater that we want to desalinate. The superhydrophilic carbonized sand demonstrated a good evaporation rate of 1.53 kg/m2h and 82% efficiency under 1 sun irradiation and upright salt rejection ability, which exhibited its capability to be used in green solar-driven water vaporization technology for sweet water production. The effects of important parameters, including light intensity, wind speed, and environment temperature, on the evaporation rate using carbonized sand as a solar collector in a solar desalination system were studied in both laboratory and real systems.

Development of a mobile wind power plant for power supply of the troops

The scientific article was published as part of the implementation of the scientific project of grant funding for 2022-2024 IRN № АР148039/0222 «Scientific and technical substantiation of the parameters and development of a wind power plant for the electric power supply of the objects of the Armed Forces, other troops and military formations of the Republic of Kazakhstan» (the study is funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan). The article presents the results of the development of a mobile wind power plant for the energy supply of troops. In the Armed Forces of Kazakhstan, there is a need to create and implement technical devices that convert wind energy into electrical energy and have no analogues. As a result of the research, a mobile wind power plant was developed, the main element of which is a pair of identical vertically arranged curved blades. The developed design can be used in any regions of Kazakhstan. The wind plant is not tied to the weather characteristics of the area, it is able to operate in low light and low winds. It can be used to ensure a guaranteed minimum power supply to military facilities in areas of centralized power supply experiencing a shortage of energy, to prevent damage from emergency and restrictive shutdowns. In addition, to provide electricity to both technological military consumers: communication equipment, radar installations, electric drives of combat systems, lighting installations, and technical military consumers: hospitals, military camps, training centers and training grounds, military facilities support units and units located in shelter, tent cities, etc.

Contributions of meteorology and nutrient to the surface cyanobacterial blooms at different timescales in the shallow eutrophic Lake Taihu

Quantitative assessments of the contributions of various environmental factors to cyanobacterial blooms at different timescales are lacking. Here, the hourly cyanobacterial bloom intensity (CBI) index, a proxy for the intensity of surface cyanobacterial biomass, was obtained from the geostationary satellite sensor Geostationary Ocean Color Imager (GOCI) over the years 2011–2018. Generalized additive model was applied to determine the responses of monthly and hourly CBI to the perturbations of meteorological factors, water stability and nutrients, with variation partitioning analysis used to analyze the relative importance of the three groups of variables to the inter-monthly variation of diurnal CBI in each season. The effects of environmental factors on surface cyanobacterial blooms varied at different timescales. Hourly CBI increased with increasing air temperature up to 18 °C but decreased sharply above 18 °C, whereas monthly CBI increased with increasing air temperature up to 30 °C and stabilized thereafter. Among all the environmental factors, air temperature had the largest contribution to the intra-daily variation in CBI; water stability had the highest explanation rate for the inter-monthly variation of diurnal CBI during summer (42.3 %) and autumn (56.9 %); total phosphorus explained the most variation in monthly CBI (18.5 %). Compared with cyanobacterial biomass (CB) in the water column, high light and low wind speed caused significantly lower CBI in July and higher CBI in November respectively. Interestingly, cyanobacterial blooms at the hourly scale were aggravated by climate warming during winter and spring but inhibited during summer and autumn. Collectively, this study reveals the effects of environmental factors on surface cyanobacterial blooms at different timescales and suggests the consideration of the hourly effect of air temperature in short-term predictions of cyanobacterial blooms.

Wind Tunnel Experiments on Volcaniclastic Dust Emission and Dispersion Initiated by Water Droplet Impact

AbstractIceland contains active dust regions within high‐latitude, cold‐climate environments. An abundant supply of particulates <10 μm in diameter (PM10) is available within its extensive glacial outwash plains and through widespread transport and deposition of volcanic ash with hydrophobic tendencies. The climate is notably wetter than dust regions located in hot deserts, so that additional processes governing dust emission must be considered, inclusive of rain splash. Field workers in Iceland report that dust emission events sometimes overlap with precipitation. This study used high‐speed photography in wind tunnel experiments to assess the influence of water droplet impact and wind shear on the detachment and suspension of particulates collected from several active dust source regions within Iceland. Concentrations of PM10 sampled downwind of a single water droplet impact reached values as high as 104 μg m−3 and were positively correlated with increasing wind speed, droplet impact velocity and angle. Our measurements demonstrate that wind shear in a turbulent flow is important for the dispersion of aerosols ejected via water droplet impact from the surface of dry sediment, and that these coincident mechanisms can be highly effective agents of erosion, especially in light winds that are normally incapable of dust entrainment. Foremost, this study provides further evidence of the complexity of dust emission in cold environments and the importance of examining this phenomenon over a wide range of temporal and spatial scale.

Guest Editorial: Polymer electrets and ferroelectrets

Guest Editorial: Polymer electrets and ferroelectrets

Circadian and seasonal flight activity differences between the sexes of the biocontrol agent Eadya daenerys (Hymenoptera: Braconidae) and the impact of host size on adult emergence

AbstractSince its accidental introduction into New Zealand in 1916, the invasive eucalypt leaf beetle Paropsis charybdis remains a pest of economic significance to Eucalyptus forestry. For this reason, the braconid parasitoid Eadya daenerys has been approved for release as a classical biological control agent. To aid in field monitoring using hand netting of biocontrol releases and laboratory rearing protocols, the flight activity over 6 a year field research program of E. daenerys and the relationships between the parasitoid and the size of its beetle hosts were evaluated in the country of origin. Wasps were observed flying over 32 days from mid‐November to mid‐December in Tasmania. E. daenerys was found to exhibit a morning‐based scramble competition mating system. Females flying in the early morning had lower mature egg loads (134.2 ± 27.6) than at other times of the day. In the first half of the season, male flight was most often seen in the early morning, whereas in the second half of the season, there was a 4.5‐fold decrease in any wasps flying. Female flight activity significantly increased to 70% female in the evening hours from 5:00 pm to 8:00 pm, which by the second half of the season was almost exclusively female. Wasps were caught flying across a wide range of air temperatures (10.7–23.8°C), humidity and light levels, but even light winds reduced flight when average wind speed exceeded 0.27 m/s for males and 0.73 m/s for females. Beetle prepupal weight was a predictor of E. daenerys parasitism success with mean beetle prepupal weights significantly higher for stung but unsuccessfully parasitised larva (62.09 mg) than those successfully parasitised (52.94 mg). The chance of an emerged wasp larva spinning a pupal cocoon was found to increase by 5% with every 1‐mg increase in its beetle prepupal weight. Heavier beetle prepupae produced bigger parasitoids. Field‐collected adult E. daenerys had larger (12%) head capsule widths (mean of 1.42 mm) than those reared in the laboratory (mean of 1.27 mm), suggesting that improving host nutrition and laboratory rearing conditions for increasing host size may help optimise E. daenerys rearing success.

From Microscopic Droplets to Macroscopic Crowds: Crossing the Scales in Models of Short-Range Respiratory Disease Transmission, with Application to COVID-19.

Short-range exposure to airborne virus-laden respiratory droplets is an effective transmission route of respiratory diseases, as exemplified by Coronavirus Disease 2019 (COVID-19). In order to assess the risks associated with this pathway in daily-life settings involving tens to hundreds of individuals, the chasm needs to be bridged between fluid dynamical simulations and population-scale epidemiological models. This is achieved by simulating droplet trajectories at the microscale in numerous ambient flows, coarse-graining their results into spatio-temporal maps of viral concentration around the emitter, and coupling these maps to field-data about pedestrian crowds in different scenarios (streets, train stations, markets, queues, and street cafés). At the individual scale, the results highlight the paramount importance of the velocity of the ambient air flow relative to the emitter's motion. This aerodynamic effect, which disperses infectious aerosols, prevails over all other environmental variables. At the crowd's scale, the method yields a ranking of the scenarios by the risks of new infections, dominated by the street cafés and then the outdoor market. While the effect of light winds on the qualitative ranking is fairly marginal, even the most modest air flows dramatically lower the quantitative rates of newinfections.

Data generation method for power system operation considering geographical correlations and actual operation characteristics

Data generation methods for power system operation are the basis for many studies such as linear power flow models and data-driven models. On the one hand, the generated data can be used to test the performance of the model. On the other hand, the generated data can be used to train the model. In actual power systems, the operating data is not completely random, but conforms to certain operating laws, and has some typical characteristics, including geographic correlations and actual operation characteristics of thermal units. Taking the geographic correlations of renewable outputs as an example, the light density or wind speed in a certain area has similar characteristics. For another example, restricted by the unit cost of generating electricity, thermal unit outputs are at a relatively stable level rather than completely random. However, existing studies have not sufficiently considered these geographic correlations and actual operation characteristics. Therefore, this paper proposes a new data generation method considering geographic correlations and actual operation characteristics of thermal units. Specifically, the proposed method includes four steps: parameter estimation, sampling, generation benchmark settings, and system operation data calculation. To accurately characterize geographic correlations and actual operation characteristics of thermal units, the Eigendecomposition and unit commitment model are introduced into the proposed method. Numerical tests verify that the proposed method can guarantee the geographical correlations and actual operation characteristics of generated data.

Improved Performance of Heat Source Free Water‐Floating Carbon Nanotube Thermoelectric Generators Controlling Wettability Using Atmospheric‐Pressure Plasma Jet and Waterproof Spray

AbstractWater‐floating carbon nanotube thermoelectric generators (CNT‐TEGs) can effectively power Internet of Things (IoT) applications. CNT‐TEGs produce electricity by floating on water to generate a temperature gradient in the CNT films, where water pumping via capillary action causes evaporation‐induced cooling in selected areas. However, the amount of electricity required for target applications needs to be increased. Therefore, the wettability of CNT films is controlled via various treatments to increase water evaporation and temperature difference in the films. The contact angle of the water droplet on the film surface related to the wettability decreases upon atmospheric‐pressure plasma jet irradiation and increases upon waterproof spray treatment. Intermediate wettability is obtained by combining the two aforementioned treatments. Under the environmental conditions of light irradiation (1 kW m−2) and wind (3 m s−1) at a water temperature of 20 °C, the CNT‐TEGs with the combined treatment exhibit a highest output voltage of 3.9 mV, which is 30% larger than that of the pristine CNT‐TEG. At a water temperature of 60 °C, a highest output voltage of 13.1 mV is achieved in the pristine CNT‐TEG. The performance enhancement of CNT‐TEGs by controlling the wettability of CNT films under various environmental conditions can facilitate advancements in IoT technology.

Development of an Objective Methodology for Identifying the Sea-Breeze Circulation and Associated Low-Level Jet in the New York Bight

Abstract In a midlatitude coastal region such as the New York Bight (NYB), the general thermodynamic structure and dynamics of the sea-breeze circulation is poorly understood. The NYB sea-breeze circulation is often amplified by and coterminous with other regional characteristics and phenomena such as complex coastal topology, a low-level jet (LLJ), and coastal upwelling. While typically considered a summertime phenomenon, the NYB sea-breeze circulation occurs year-round. This study creates a methodology to objectively identify sea-breeze days and their associated LLJs from 2010 to 2020. Filtering parameters include surface-based observations of sea level pressure (SLP) gradient and diurnal tendencies, afternoon wind speed and direction tendencies, air temperature gradient, and the dewpoint depression. LLJs associated with the sea-breeze circulation typically occur within 150–300 m MSL and are identified using a coastal New York State Mesonet (NYSM) profiler site. Along coastal Long Island, there are on average 32 sea-breeze days annually, featuring winds consistently backing to the south and strengthening at or around 1800 UTC (1400 EDT). The NYB LLJ is most frequent in the summer months. Sea-breeze days are classified into two categories: classic and hybrid. A classic sea breeze is driven primarily by both cross-shore pressure and temperature gradients, with light background winds; while a hybrid sea breeze occurs in combination with other larger-scale features, such as frontal systems. Both types of sea breeze are similarly distributed with a maximum frequency during July.

Insights from the first winter weather observations near Mount Everest's summit

Insights from the first winter weather observations near Mount Everest's summit

AirSeaFluxCode: Open-source software for calculating turbulent air-sea fluxes from meteorological parameters

The turbulent exchanges, or fluxes, of heat, moisture and momentum between the atmosphere and the ocean play a crucial role in the Earth’s climate system. Direct measurements of turbulent fluxes are very challenging and sparse, and do not span the full range of environmental conditions that exist over the ocean. This means that empirical “bulk formulae” parameterizations that relate direct flux observations to concurrent measurements of the mean meteorological and sea surface variables contain considerable uncertainty. In this paper, we present a Python 3.6 (or higher) open-source software package “AirSeaFluxCode” for the computation of the heat (latent and sensible) and momentum fluxes. Ten different parameterizations are included, each based on published descriptions or code and each derived from a different set of observations, or different assumptions about the turbulent exchange processes. They represent a range of current expert opinion on how the fluxes depend on mean properties and can be used to explore uncertainty in calculated fluxes. AirSeaFluxCode also allows the adjustment of the mean meteorological input parameters (air temperature, humidity and wind speed) from the height at which they are obtained to a user-defined output height. This height adjustment enables the comparison of measurements, or model-derived values, made at different heights above sea-level. The parameterizations calculate the fluxes using input parameters that are relatively easily to measure, or are available as model output: wind speed, air temperature, sea surface temperature, atmospheric pressure and humidity. Where original code is available we have compared its output with that of AirSeaFluxCode. Any changes made to increase consistency across algorithms by standardizing computational methods or calculation of meteorological variables, for example, are discussed and the impacts quantified: these are shown to be insignificant except for a few cases where conditions were extreme, and AirSeaFluxCode is shown to be robust. We also investigate the impact on the fluxes caused by different assumptions about the exchange processes, or the choices inherent in the implementation of the parameterizations. For example, sea surface temperature usually refers to data typically obtained at depths of between 1 and 10 m. However, since some parameterizations require a “skin” sea surface temperature, code that adjusts temperature at depth to skin temperature is included: this has a very significant impact on the fluxes. Selecting a parameterization that is appropriate for the available sea surface temperature will avoid the need to adjust the sea temperature data and the uncertainties associated with that adjustment, and will also avoid the biases due to use of the “wrong” measure of temperature. Significant differences also resulted from assumptions about the size of reduction in sea surface humidity to account for salinity effects: the uncertainty in the reduction factor needs to be quantified in future analyses. Fluxes in extreme conditions are particularly uncertain since the transfer coefficients in the different parameterizations vary most at very high and very low wind speeds. Low wind speeds are also challenging for numerical implementation since choices have to be made regarding: convergence criteria for the iterative calculation, inclusion of a parameterization for convective gustiness, or application of ad hoc limits to various parameters. All of these choices can significantly affect the flux estimates for light winds.

Effect of Indoor Condition with Cross Ventilation on Deposition of Airborne Droplets Emitted from Human Cough

Prediction of airborne transmission in different environmental condition remains as the research challenge in the field. This has motivated the present study to obtain the direct impact of flow field to the physical nature of transmission. ANSYS Fluent 2022 R1 software is utilised in this research to numerically investigate and visualize flow pattern in a closed environment with cross ventilation and its effect to the emitted droplets deposition. The effect of different indoor parameters towards airborne transmission are investigated, which include wind velocity, air relative humidity (RH), and exposure time after emission. Simulation result revealed increasing wind velocity according to Beaufort wind scale of 1.0 to 3.9 m/s, increases transmission rate due to enhanced convection effect. Surrounding air with higher RH leads to a larger mean diameter of particles due to hygroscopic growth effect, while evaporation effect dominates in lower air RH, leading to particle shrinkage. In a light wind breeze, droplet mass of 5.15 mg deposited on receiver body within 0.5 s of transmission when RH is 40%, while only 3.29 mg droplets reached receiver in RH of 99.5%. Droplet particles settle on the floor within 1.50 s revealed 0.66 mg deposited mass in higher RH, while 0.26 mg of droplets deposited in lower RH. Deposition at transmitter body is possible due to recirculation effect of incoming wind generated between transmitter and receiver, leading to 3.7 times higher deposited mass in lower RH as compared to in higher RH. This research highlights application of Euler-Lagrange model to represent the trajectory of cough droplets influenced by indoor condition with horizontal wind, in the effort to strengthen safety and health judgement in the event of a pandemic.

The Influence of Regional Meteorology on Carbon Emissions from California Wildfires

Abstract This paper examines the relationship between daily carbon emissions for California’s savanna and forest wildfires and regional meteorology over the past 18 years. For each fuel type, the associated weather [daily maximum wind, daily vapor pressure deficit (VPD), and 30-day-prior VPD] is determined for all fire days, the first day of each fire, and the day of maximum emissions of each fire at each fire location. Carbon emissions, used as a marker of wildfire existence and growth, for both savanna and forest wildfires are found to vary greatly with regional meteorology, with the relationship between emissions and meteorology varying with the amount of emissions, fire location, and fuel type. Weak emissions are associated with climatologically typical dryness and wind. For moderate emissions, increasing emissions are associated with higher VPD from increased warming and only display a weak relationship with wind speed. High emissions, which encompass ∼85% of the total emissions but only ∼4% of the fire days, are associated with strong winds and large VPDs. Using spatial meteorological composites for California subregions, we find that weak-to-moderate emissions are associated with modestly warmer-than-normal temperatures and light winds across the domain. In contrast, high emissions are associated with strong winds and substantial temperature anomalies, with colder-than-normal temperatures east of the Sierra Nevada and warmer-than-normal conditions over the coastal zone and the interior of California. Significance Statement The purpose of this work is to better understand the influence of spatially and temporally variable meteorology and spatially variable surface fuels on California’s fires. This is important because much research has focused on large climatic scales that may dilute the true influence of weather (here, high winds and dryness) on fire growth. We use a satellite-recorded fire emissions dataset to quantify daily wildfire existence and growth and to determine the relationship between regional meteorology and wildfires across varying emissions in varying fuels. The result is a novel view of the relationship between California wildfires and rapidly variable, regional meteorology.

An evaluation of meteorological data prediction over Washington, D.C.: Comparison of DCNet observations and NAM model outputs

This study presents an example of how outputs of operational and readily-available mesoscale numerical models can be adapted to initialize dispersion calculations within the urban surface roughness layer. Three years of urban meteorological observations from central Washington, DC, are compared against forecast outputs of the North American Mesoscale (NAM) model. NAM wind speed predictions underestimate the observations in light winds and overestimate the measurements in high winds. Average wind directions are consistent. However, an adjustment of the predicted direction of the plume by −20° is needed. The uncertainty associated with this adjustment is large in light NAM wind speed with no evident variation by season. The values of the standard deviation of the wind direction, σθ derived from NAM model outputs underestimate the observations by a small amount (about −1.5 to −2.5°). The results presented here indicate that mesoscale numerical model outputs can provide information adequate for dispersion calculations. However, levels of uncertainty associated with implementation of the suggested procedures increase with decreasing wind speed, causing considerable uncertainty in the implementation of adjustments as low wind speed conditions are approached. Results and recommendations reported here should not be extended to other numerical models or other cities without further testing.

Recent Advancement in Savonius Wind Turbine- A Review

In the steps to save our earth from global warming every nation focused on their own way to promote green energy among which the Savonius vertical axis wind turbine is one of the excellent viable solutions for scavenging wind energy in a downtown background, due to distinctive characteristics such as compactness, self-starting ability at light wind, minimum noise level, with relatively reasonable price and simple assembly. However, the traditional Savonius Wind Turbines with semicircular blades has a proportionately low power coefficient together with a high negative torque produced by the returning blade is a crucial disadvantage of this rotor. This work focuses on reviewing and giving an overview on the form of the wings of Savonius Vertical Axis Wind Turbine. This paper also aims to give a run through of the several augmentation approaches used in Savonius rotor over the last four decades. In this paper, a brief on all possible segments and parts of the machine is given after a brief analysis and research on each topic.

The Silent Turn in Onutė Narbutaitė’s Creative Work: A Longing for the Existentialist Era

Onutė Narbutaitė’s recent works exemplify her exceptional propensity for existentialist literature. Combined with views of the epoch, these works were inspired by the Thomas Mann Festival in Nida and revealed the composer’s inner world of suggestions, contexts, and colours. The placing of context in music became the new existentialist space in the composer’s work. Her style is formed, respectively, from the dramaturgical vaults of minimalism (Interludium, 1983) to the vibrating spectral soundscapes that purify fragility and penetration and link the sound of wind and a tense string with non-existence. Among such works is the trilogy that had evolved at the concert of Narbutaitė’s music at St Catherine’s Church on 17 November 2018. In her comments, Narbutaitė emphasises the unifying depth of these works: the fragility of the relationship between sound and silence, darkness and light, and the visual context breaking into the musical space. Primarily, it is an existential aspect of tension of stringed instruments in Was There a Butterfly? for chamber orchestra (2013), Just Strings and Light Wind above Them for string quartet (2017), and the trilogy of the author’s concert: Labyrinth for soprano and flute (2017), In the Emptiness for piano (2016), and Heliography for female voice, viola, cello, and Persian drums (2015). Being together with the authors of texts – Ingeborg Bachmann, Jorge Luis Borges (Labyrinth), Edmundas Gedgaudas, Vaidotas Daunys – is also very significant for the composer, because she herself is a poet longing for poetic expressionism. They add the touch of sound and silence with the meaning of the diary experience currently permeating Narbutaitė’s creative work and shaping her musical style with the semantic codes of expression of existentialist philosophy: tense strings, vibrating spaces, the soundscape prevailing at the edge of harmony and destruction – the glow of the European sunset.