Distinct Weather Conditions Research Articles

Growth response of oaks to insect defoliation: Immediate and intermediate perspectives

In this study, we investigate the immediate and short-term consequences of defoliation by the spongy moth Lymantria dispar on secondary growth of oaks (Quercus robur L. and Quercus petraea (Matt.) Liebl.), including the interplay between defoliation and water availability during the defoliation period within a large-scale field experiment in south-eastern Germany. Furthermore, the impact of defoliation on oak secondary growth is explored retrospectively based on tree core measurements.Within the large-scale filed experiment, secondary growth of 880 oaks in 44 oak-dominated stands was monitored using permanent girth tapes over a three-year period following a spongy moth outbreak. Insecticide treatments were applied to half of the plots to obtain trees without defoliation, and canopy cover dynamics were subsequently monitored ground based and from satellites in all plots.We found that moth defoliation significantly reduced oak secondary growth by 10–60% during the outbreak year, with the impact on secondary growth being directly proportional to defoliation intensity. The negative impact of defoliation on secondary growth was aggravated by increased water availability during the outbreak year.In the post-outbreak year, secondary growth of oaks that had endured mild defoliation was no longer different from that of non-defoliated oaks. In contrast, oaks that had experienced substantial defoliation still exhibited a significant 10–30% reduction in secondary growth. Regardless of defoliation intensity, no further reduction in secondary growth was detected two years after the event compared to control trees. Our complementary retrospective analysis, utilizing core samples from oaks previously subjected to a defoliation event under distinct weather conditions, disclosed a strikingly analogous recovery of secondary growth from defoliation instigated by the spongy moth. Thus, validating that our experimental findings possess broad temporal transferability.

Balancing heat saving and supply in local energy planning: Insights from 1970-1989 buildings in three European countries

This study investigates the cost balance between heat energy savings through building envelope retrofits and supply from low-carbon decentralised and centralised technologies in a generic urban district, composed of residential and non-residential buildings from the 1970–1989 construction period. For generalisability, the district is analysed in three European countries (Bulgaria, Germany, Finland), each with distinct weather conditions and price levels. Using bottom-up energy modelling and adopting a societal perspective that includes external costs, the study finds the cost-effectiveness of retrofits to be context-specific. In Bulgaria, retrofits prove largely cost-effective, whereas in Germany and Finland, high labour and material costs pose challenges. Heat pumps, whether decentralised in buildings or centralised in district heating systems, emerge as key options for heat supply, even in cold climates. The study underscores the importance of integrated energy planning in line with the ‘energy efficiency first’ principle and corresponding incentive structures to promote sustainable urban energy systems.

Design and investigation of hybrid PON‐FSO system employing modified NZCC code under distinct weather conditions

AbstractIn this paper, a hybrid time and wavelength division multiplexing passive optical network (TWDM‐PON) and wavelength division multiplexing optical code division multiple access (WDM‐OCDMA) with free space optics (FSO) for bidirectional 160/40 Gbps transmission has been proposed. Also, to offer the information to 64 users over 60 km fiber and 600 m FSO channels under diverse climate conditions have been presented. Also, to resist the fiber impairments, interference, noise and losses under the effect of unfavorable climate conditions in hybrid fiber‐FSO link, a modified new zero‐cross correlation (NZCC) code is effectively used in the system to enhance the system ability to access shared bandwidth with users' security. The performance of the designed PON system has been analysed and investigated for diverse FSO (10–600 m) and fiber distance (0–60 km) under distinct climate conditions. Based on mathematical and simulation analysis, the designed system using modified NZCC code is shown to provide better performance than other OCDMA codes. The designed system with hybrid fiber‐FSO link improves the performance of the system in terms of high received optical power of 3 dBm and support 110 users simultaneously at acceptable BER of 10−9, under fiber impairments, climate conditions and turbulences. Additionally, on comparing the designed system's performance with the prior latest work in literature reveals its superiority than others in codes and system design.

Linkage between mangrove wetland dynamics and wave attenuation during a storm–a case study of the Nanliu Delta, China

Frequently, large-scale typhoon-induced casualties and financial losses in global mega-delta cities can be buffered to a large extent by the presence of mangrove wetlands occurring in tropical coastal zones. However, there is little information about how mangrove wetland dynamics induce wave energy damping. Here, a series of biomorphodynamic field data was acquired during a storm period induced by Typhoon Sinlaku over a mangrove wetland in the Nanliu Delta, the largest delta of the northern Beibu Gulf in China; these data revealed the wave attenuation process of native Aegiceras corniculatum (AC). The results indicated that the wave damping coefficient of AC was higher during the storm period than during normal weather conditions. Sapling and adult AC were densely distributed in the field and had a greater effect on reducing wave height than seedlings, which were sparsely distributed, even though seedlings might have a stronger damping ability. Moreover, wave height was linearly attenuated with landward wave propagation distance along a transect of AC plots of different ages. Our work further indicated that the slopes and intercepts of the linear fits between wave height and landward wave propagation distance under storm and normal conditions were closely related to incident wave height, the water level and submerged vegetation volume. These results highlight the role of AC trees of different ages and densities under distinct weather conditions in the wave attenuation process.

Assessment of a meteorological mesoscale model's capability to simulate intra-urban thermal variability in a tropical city

Model-based studies investigating the spatial and temporal variability of air temperature are commonly employed to assess heat mitigation strategies in cities. To generate reliable predictions, it is therefore important that models are capable to accurately predict air temperature variability across the city to account for the local climate context. The present study explores the sensitivity of the Weather Research and Forecasting (WRF) model coupled with a multi-layer urban scheme (BEP-BEM) to simulate intra-urban variations of 2-m air temperature during different synoptic conditions in the tropical city-state of Singapore. Two one-month long simulations are conducted during a relatively wet period during the Southwest monsoon and a very dry period during the Northeast monsoon. Model evaluation with micrometeorological data collected at an eddy covariance flux tower shows an overall good performance for turbulence parameters and surface energy balance components, in particular during dry conditions. Difficulties in predicting intermittent cloud cover result in slightly higher errors of modelled 2-m air temperature during the wet period (RMSE<2.3∘C) compared to the dry period (RMSE<1.6∘C) when using data from nine locations with different urban morphologies. The present research demonstrates the model's capability to predict the intra-urban variability across distinct urban morphologies under distinct weather conditions. However, the model fails to accurately capture the magnitude of the observed nocturnal temperature differences across all weather conditions investigated.

Distinct weather conditions and human mobility impacts on the SARS-CoV-2 outbreak in Colombia: Application of an artificial neural network approach.

The coronavirus disease 2019 (COVID-19) is still spreading fast in several tropical countries after more than one year of pandemic. In this scenario, the effects of weather conditions that can influence the spread of the virus are not clearly understood. This study aimed to analyse the influence of meteorological (temperature, wind speed, humidity and specific enthalpy) and human mobility variables in six cities (Barranquilla, Bogota, Cali, Cartagena, Leticia and Medellin) from different biomes in Colombia on the coronavirus dissemination from March 25, 2020, to January 15, 2021. Rank correlation tests and a neural network named self-organising map (SOM) were used to investigate similarities in the dynamics of the disease in the cities and check possible relationships among the variables. Two periods were analysed (quarantine and post-quarantine) for all cities together and individually. The data were classified in seven groups based on city, date and biome using SOM. The virus transmission was most affected by mobility variables, especially in the post-quarantine. The meteorological variables presented different behaviours on the virus transmission in different biogeographical regions. The wind speed was one of the factors connected with the highest contamination rate recorded in Leticia. The highest new daily cases were recorded in Bogota where cold/dry conditions (average temperature <14 °C and absolute humidity >9 g/m3) favoured the contagions. In contrast, Barranquilla, Cartagena and Leticia presented an opposite trend, especially with the absolute humidity >22 g/m3. The results support the implementation of better local control measures based on the particularities of tropical regions.

Seasonal variation in sowing and its effect on ethanol and biomass yield of sweet sorghum

ABSTRACT This paper compares and assesses various sweet sorghum genotypes in terms of their biological yield, juice yield and computed ethanol at four different sowing dates. Twenty-three genotypes and one hybrid were examined and the study reveals that RSSH-50 recorded higher values for plant height, stem girth, photosynthetically active radiation, juice yield, computed ethanol yield, fresh biomass yield and harvest index during the rainy season. In contrast, CSV-19SS showed significantly higher green cane yield and computed ethanol yield followed by RSSV-454, RSSV-446 and RSSV-545 during the summer. The variations in different seasons were due to the distinct weather and climatic conditions. Thus, crops that are sown in late rainy, timely summer and late summer take longer to attain physiological maturity and have reduced biological yield than crop sown in the timely rainy season. Among all genotypes, RSSV-260, SPV-2057, RSSV-540, CSV-19SS and hybrid RSSH-50 during the rainy season and CSV-19SS, RSSV-453 and RSSV-545 during the summer showed balanced performances in terms of ethanol and biomass yield.

Tailored Algorithms for Anomaly Detection in Photovoltaic Systems

The fastest-growing renewable source of energy is solar photovoltaic (PV) energy, which is likely to become the largest electricity source in the world by 2050. In order to be a viable alternative energy source, PV systems should maximise their efficiency and operate flawlessly. However, in practice, many PV systems do not operate at their full capacity due to several types of anomalies. We propose tailored algorithms for the detection of different PV system anomalies, including suboptimal orientation, daytime and sunrise/sunset shading, brief and sustained daytime zero-production, and low maximum production. Furthermore, we establish simple metrics to assess the severity of suboptimal orientation and daytime shading. The proposed detection algorithms were applied to a set of time-series of electricity production in Portugal, which are based on two periods with distinct weather conditions. Under favourable weather conditions, the algorithms successfully detected most of the time-series labelled with either daytime or sunrise/sunset shading, and with either sustained or brief daytime zero-production. There was a relatively low percentage of false positives, such that most of the anomaly detections were correct. As expected, the algorithms tend to be more robust under favourable rather than under adverse weather conditions. The proposed algorithms may prove to be useful not only to research specialists, but also to energy utilities and owners of small- and medium-sized PV systems, who may thereby effortlessly monitor their operation and performance.

Identification of Dengue Serotypes using a Single Serum Specimen Algorithm in a Tertiary Care Hospital, Alappuzha, Kerala, India

Introduction: The geographic location of Alappuzha, a district in the South Indian state of Kerala, the distinct weather conditions and frequent natural calamities present a unique ecology that contributes to the prevalence of vector-borne diseases like dengue. Early dengue virus infection can be detected by using a combination of tests on a single serum specimen. Aim: To identify the dengue virus serotypes among hospitalised patients in a South Indian teaching hospital in Alappuzha, Kerala, India. Materials and Methods: Patient samples that tested positive for dengue non-structural protein-1 (NS1) antigen by ELISA were further evaluated for dengue virus RNA by real-time, multiplex reverse transcriptase Polymerase Chain Reaction (PCR) and the serotype was determined. Anonymised patient data was collected using a questionnaire as a data collection tool. The data was analysed for statistical significance. Results: Among 422 non-duplicate patient serum samples received in the Department of Microbiology, in the year 2019, 30 were positive for dengue NS1 antigen by ELISA. Dengue viral RNA was detected in 50% of the samples (15/30). DENV-3 serotype was the most prevalent (nine) followed by DENV-1 (five) and DENV-2 (one). Common presentations of the patients were fever, headache, and myalgia. No statistically significant association was found between a PCR positive result and the presence of warning signs and thrombocytopenia. Conclusion: DENV-3 was the most common serotype in the study population. Early dengue virus infection is associated with varied symptoms.

Statistička obrada podataka o vremenskim neprilikama u svrhu određivanja mjesečnog intervala s matematički očekivanim danima zastoja pri radu gradilišta na području grada Rijeke

Meteorološki i klimatski uvjeti mogu uvelike utjecati na kontinuirani i zadovoljavajući tijek izvođenja radova na gradilištu. Posebno je važno, ali nedovoljno primijenjeno u praksi, prilikom izrade vremenskog plana i definiranja roka za građenje uzeti u obzir i moguće zastoje pri radu gradilišta zbog nepovoljnih vremenskih uvjeta. Meteorološki i klimatski uvjeti imaju različit utjecaj ovisno o lokaciji gradilišta. Iz tog razloga, kako bi se statistički obradio utjecaj vremenskih neprilika na području grada Rijeke, s pripadajućom umjereno toplom, vlažnom klimom i vrućim ljetima (Cfa - Köppen-ova klasifikacija klime), od Državnog hidrometeorološkog zavoda (DHMZ) zatraženi su meteorološki podaci o vremenskim neprilikama za vremensko razdoblje od 25 godina, izmjerenih i zabilježenih u glavnoj meteorološkoj postaji u gradu Rijeci. Vremenske neprilike za koje su zatraženi podaci, a koje su karakteristične za klimatsko područje grada Rijeke, su Oborine (≥ 10 mm), Olujni vjetar, Hladni dani (Tmin &amp;lt; 0 °C) i Vrući dani (Tmax ≥ 30 °C). Zatraženi meteorološki podaci su u obliku ukupnog broja dana u mjesecu sa zabilježenim djelovanjem pojedine vremenske neprilike. Ciljevi ovog rada su, primjenom odgovarajućih statističkih testova, testiranje različitosti na razini značajnosti od 5 %, među skupinama vremenskih neprilika (Kruskal-Wallis test, Mann-Whitney test) te, zatim, određivanje 95 % pouzdanog intervala s matematički očekivanim danima zastoja pri radu gradilišta za svaki mjesec pojedinačno (intervalna procjena očekivanja u skupini s normalnom distribucijom podataka). Mjesečni intervali dobiveni statističkom obradom s matematički očekivanim danima zastoja, zbog vremenskih neprilika predstavljaju vrijedan ulazni parametar u svrhu preciznije izrade vremenskog plana i definiranja roka za građenje na području grada Rijeke.

Effects of alternate wetting and drying technique on greenhouse gas emissions from irrigated rice paddy in Central Luzon, Philippines

ABSTRACTAlternate wetting and drying (AWD) technique has been widely reported to reduce methane (CH4) emission from irrigated rice paddies. However, little is known about its feasibility in an environment that has distinct weather conditions involving tropical wet season (WS). To investigate the AWD’s feasibility in terms of reducing greenhouse gas (GHG) emissions both in dry season (DS) and WS, 3-year field experiments were conducted in Central Luzon, Philippines. Three treatments of water management were continuous flooding (CF), flooding when surface water level naturally declines to 15 cm below the soil surface (AWD), and site-specific AWD that modified the criteria of soil drying (AWDS). Methane and nitrous oxide (N2O) fluxes were measured using a closed chamber method, and the global warming potential (GWP) of the two GHGs was calculated. Rice grain yield did not significantly differ among treatments. In accordance with the previous findings, the seasonal total CH4 emission was significantly greater in WS than in DS. The effect of treatment was significant, but the reduction rate by AWD was just 1.7% compared to CF. The seasonal total N2O emission was significantly affected by cropping season and treatment. The AWD increased the N2O emission by 97%, especially in DS. The resultant GWP did not significantly differ among three treatments. The results indicate that the AWD and AWDS with the current settings were insufficient to reduce the annual GHG emissions in this site. However, fragmentary results obtained in the last DS suggest that an earlier rice residue incorporation and keeping dry soil conditions in the preceding fallow season is effective in reducing CH4 emission in combination with an earlier implementation of AWD.

Field Permeability Tests Using Organic Liquids in Compacted Brazilian Soils

This paper presents results of field and laboratory permeability tests aimed at evaluating the performance of mineral barriers for the containment of organic liquids (Non Aqueous Phase Liquids, NAPL). Experimental landfills were constructed following optimal ranges of variation of soil index properties proposed previously and the performance of the landfills was evaluated under two distinct weather conditions (rainy and dry periods). A primary test campaign was performed during the rainy period (March to August). Then a second testing campaign was performed from November 2013 to January 2014 (months of low rainfall). The obtained results corroborate several results published in the technical literature: fluids with a low dielectric constant (non polar) tend to present higher intrinsic permeability (K) than polar fluids and the presence of water, the most wettable fluid, reduces the NAPL permeability. Soils with a higher plasticity index, IP, presented higher Kw/KNAPL, (ratio water/NAPL intrinsic permeability) showing that the values of K are dependent on the interactions between solid particles and interstitial fluid. Based on laboratory and field results, optimal ranges of variation of soil index properties are proposed for the construction of mineral barriers for organic liquid containment.

Mathematical formulation and demonstration of a dynamic system-level ship thermal management tool

This paper presents the mathematical formulation and unique capability of a system-level ship thermal management tool, vemESRDC, developed to provide quick ship thermal responses in early design stages. The physical model combines principles of classical thermodynamics and heat transfer, along with appropriate empirical correlations to simplify the model and expedite the computations. As a result, the tool is capable of simulating dynamic thermal response of an entire ship, characterized by intricate thermal interactions within a complex ship structure, within an acceptable time frame. In this work, vemESRDC is demonstrated through three case studies in which transient thermal responses of an all-electric ship to different ship operation modes, weather conditions, and partial loss of cooling are investigated. The analysis examines particularly the following: (1) the required cooling capacities to maintain each ship component within its design limit; (2) equipment temperature variations with respect to partial cooling loss in battle mode; and (3) the assets of installing seawater heat exchangers to pre-cool deionized freshwater before chillers. For the notional all-electric ship conceived and assessed in this work, the results verify the capability of vemESRDC to capture dynamic thermal interactions between shipboard equipment and their respective surroundings and cooling systems, e.g., the tool provides practical insights into pulse load cooling strategy, and different solutions are obtained for distinct weather conditions. In addition to the case studies performed in this work, vemESRDC can be employed to conduct diverse studies based on which concrete ship thermal management strategies can be formulated in early design stages.

Influence of peat soils on runoff process: case study of Vydra River headwaters, Czechia

This paper summarizes findings from the hydrological research in the Vydra River headwaters, the Šumava Mts., s-w Czechia, dealing with the hydrological function of local peat soils and their effect on the outflow from the basin. This study represents a part of a long-term research carried out at the Faculty of Science, Charles University in Prague. The paper shows how important it is to study the groundwater level in peat soils and its area in a catchment as well as to predict the outflow in distinct weather conditions. There were chosen four small experimental catchments with different peat and waterlogged forest coverage. Rainfall events were selected in various periods within a year with a varying groundwater level (maximum and minimum) in the peat bog. Within these situations flood wave volumes were calculated and all of them were compared regarding the peat bog extension. The presented research also compares various sources of data about peat soils areas and areas of waterlogged forest.

A time series analysis of multiple ambient pollutants to investigate the underlying air pollution dynamics and interactions

Understanding the temporal dynamics and interactions of particulate matter (PM) concentration and composition is important for air quality control. This paper applied a dynamic factor analysis method (DFA) to reveal the underlying mechanisms of nonstationary variations in twelve ambient concentrations of aerosols and gaseous pollutants, and the associations with meteorological factors. This approach can consider the uncertainties and temporal dependences of time series data. The common trends of the yearlong and three selected diurnal variations were obtained to characterize the dominant processes occurring in general and specific scenarios in Taipei during 2009 (i.e., during Asian dust storm (ADS) events, rainfall, and under normal conditions). The results revealed the two distinct yearlong NOx transformation processes, and demonstrated that traffic emissions and photochemical reactions both critically influence diurnal variation, depending upon meteorological conditions. During an ADS event, transboundary transport and distinct weather conditions both influenced the temporal pattern of identified common trends. This study shows the DFA method can effectively extract meaningful latent processes of time series data and provide insights of the dominant associations and interactions in the complex air pollution processes.

Chronological Probability Model of Photovoltaic Generation

This paper proposes a chronological probability model of photovoltaic (PV) generation on the basis of conditional probability and nonparametric kernel density estimation. In addition to randomness of PV power, the correlation of PV powers between adjacent time points and the uncertainty of start and end moments of PV output can be represented. The proposed model can be employed to produce random PV power time series curve using a stochastic sampling method. The power data of three PV generators in different regions with distinct weather conditions and 34-node distribution network are used to demonstrate the correctness, effectiveness, and adaptability of the presented model.

Field Behavior on Polymer-Covered Overhead Conductors Submitted to Natural Aging on Diverse Weather and Geographic Conditions in Brazil

This work presents the mechanical and electrical field behavior results of polymer-covered overhead conductors submitted to natural aging. Experimental spacer cable lines were exposed to distinct weather conditions and environmental stresses in Northern and Southern Brazil. The main goal of these experimental lines was the development of a field laboratory for long-term evaluation of electrical equipment used in spacer cable lines submitted to natural aging and under normal operational conditions. Polymer-covered overhead conductors were evaluated by scanning electron microscopy, surface resistivity measurements, dielectric strength, tracking resistance and abrasion resistance tests. It was observed that environmental stresses such as sunlight radiation, relative humidity and other variables have strong influence upon long-term performance on polymer-covered overhead conductors.

Intercomparison between aerosol optical properties by a PREDE skyradiometer and CIMEL sunphotometer over Beijing, China

Abstract. This study compares the aerosol optical and physical properties simultaneously measured by a SKYNET PREDE skyradiometer and AERONET/PHOTONS CIMEL sunphotometer at a location in Beijing, China. Aerosol optical properties (AOP) including the Aerosol Optical Depth (AOD), Angstrom exponent (α), volume size distribution, single scattering albedo (ω) and the complex refractive index were compared. The difference between the two types of instruments was less than 1.3% for the AOD and less than 4% for the single scattering albedo below the wavelength of 670 nm. There is a difference between the volume size distribution patterns derived from two instruments, which is probably due to difference of measurement protocols and inversion algorithms for the respective instruments. AOP under three distinct weather conditions (background, haze, and dust days) over Beijing were compared by using the retrieved skyradiometer and sunphotometer data combined with MODIS satellite results, pyranometer measurements, PM10 measurements, and backtrajectory analysis. The results show that the significant difference of AOP under background, haze, and dust days over Beijing is probably due to different aerosol components under distinct weather conditions.

Prevalence, Awareness, Treatment, and Control of Hypertension in Rural Adults from Liaoning Province, Northeast China

Liaoning Province is located in northeast China, which has distinct weather conditions, geographic characteristics and lifestyles compared with other regions of the country; the lifestyle differences are especially pronounced in the rural parts of this region, where there is a dearth of financial and other resources. However, information on the prevalence, awareness, treatment, and control of hypertension in these impoverished areas is very scarce. We therefore performed multistage cluster random sampling of a group of 29,970 adult residents (>or=5 years of residency; >or=35 years of age) of the rural portions of Liaoning Province from 2005 to 2006. The sampling included a survey on blood pressure and associated risk factors. The overall prevalence of hypertension in the community was 36.2%, and 73.0% of hypertensives were unaware of their condition. Among the total group of hypertensives, only 19.8% were taking prescribed medication to lower their BP, and 0.9% had controlled hypertension. Of all subjects, 46.4% did not think that high blood pressure would endanger their lives. As to the reasons given by hypertensives who were aware of their hypertension for not taking antihypertensive medication, 47.4% reported that they lacked knowledge about the mortality of hypertension. The average salt intake in hypertensives was 16.6+/-9.9 g/day, and the percentages of smoking (44.3%), drinking (31.7%) and salt intake>6 g/day (86.8%) in hypertensives were high. Logistic regression analysis indicated that the relative risks (95% confidence interval [CI]) of overweight, obesity, smoking, drinking, increased salt intake and family history of hypertension for hypertension were 1.95 (range, 1.82-2.08), 2.92 (2.40-3.55), 1.19 (1.12-1.27), 1.16 (1.08-1.25), 1.26 (1.20-1.33) and 2.85 (2.66-3.05), respectively. A higher education level was found to be a protective factor. In conclusion, the prevalence of hypertension in adults living in the rural parts of Liaoning Province was high, and the rates of awareness, treatment, and control were unacceptably low, which may have been due to unique geographical characteristics, unwholesome lifestyles, greater sodium intake, lower education levels, and genetic risk factors.

A Probabilistic Approach for Secondary Arc Risk Assessment

A probabilistic methodology for secondary arc extinction time calculations is presented. The proposed approach permits the calculation of the probability of secondary arc extinction as a function of time and represents an extension of the well-known deterministic model proposed in , where the extinction time is obtained from EMTP-type simulations and groups of secondary arc reignition voltage curves. Instead of using only one pessimistic characteristic, a probability distribution is evaluated to randomly select the reignition voltage curve to use for each calculation. As opposed to the deterministic methods, the proposed probabilistic approach allows the assessment of the risk undertaken by a power system under different single-pole reclosing time schemes and distinct weather conditions alike.