Number Of Sunshine Hours Research Articles

Vitamin D Status and Analysis of Specific Correlates in Preschool Children: A Cross-Sectional Study in Southern Croatia.

Vitamin D deficiency is a globally important problem, particularly in children, but there is a lack of information regarding this deficiency in preschool children from southeastern Europe. This study aimed to establish the levels of 25-hydroxyvitamin D (25(OH)D) and associations of gender, time spent outdoors, physical activity (PA), and body mass index (as predictors) with the 25(OH)D level (outcome) in healthy preschool children. The participants were preschoolers (all 5–6 years of age) from southern Croatia. All the participants were tested during their mandatory medical examination 6–7 months prior to school enrollment. The PA was obtained using the preschool-age physical activity questionnaire (Pre-PAQ), which categorizes PA into five levels (from sedentary to vigorous PA). The prevalence of 25(OH)D deficiency was high: 58% of the children had 25(OH)D levels of <50 nmol/L (deficiency), and an additional 29% had an insufficient level of 25(OH)D (50–75 nmol/L). Boys had higher levels of 25(OH)D than girls. A multinomial regression using 25(OH)D categories as the outcome and a sufficient level (>75 nmol/L) as the reference value identified gender as the only significant predictor of 25(OH)D status, with boys being at lower risk for 25(OH)D deficiency than girls. These results showed a high prevalence of 25(OH)D deficiency in preschoolers from the southern part of Croatia, which is additionally alarming based on the geographical position of the studied region (42° N) and its high number of sunshine hours (>2600 h per year). Future studies examining other potential correlates of 25(OH)D in the region are warranted.

Evaluation of sunshine duration and temporal–spatial distribution based on geostatistical methods in Iran

The present study made use of daily and monthly sunshine duration hours per day data from Islamic Republic of Iran Meteorological Organization from 1974 to 2005. Various methods have used geostatistical interpolation. With the cross-validation method and analysis of validation criteria, the empirical Bayesian kriging with is future to have better performance for the temporal–spatial distribution. The results indicate there is enough sunshine duration, i.e., 5 h per day during the cold period of the year, and in the warm period, the figure increases to more than 10 h. While sunshine duration has an upward trend, cloudiness shows a downward trend in Iran. The spatial distribution of sunshine duration is strongly influenced by local conditions. On the coast of the Caspian Sea, which has a high latitude and the longest days, the least sunshine duration occurs in all seasons. Even in south coast, which has a lower latitude, a reduction in the sunshine duration hours takes place in warm months because of the cloudiness along the coastal regions. Desert regions with the arid climatic in the center, south and east of Iran enjoy the maximum sunshine duration hours. In the western half of the country due to unevenness density, the number of sunshine hours is less than the eastern half. Eastern, central and southeastern regions in Iran have the most optimal sunshine duration. In general, the sunshine duration increases from north to south.

Spatiotemporal Assessment of Drought Related to Soybean Production and Sensitivity Analysis in Northeast China

AbstractDrought is a typical disaster in the main soybean production area of northeast China. The spatiotemporal variations of drought related to soybean production based on a crop water deficit index (CWDI) and sensitivity to meteorological variables were investigated in northeast China using daily meteorological data from 87 weather stations from 1981 to 2010. Statistical analysis revealed that precipitation could not meet the water demands of soybeans during the seedling–branching, filling, and maturing stages, and excessive drought occurred more often in northeast China. The Mann–Kendall test indicated that the soybean CWDI significantly increased during the filling stage. Kriging spatial analysis showed that the most drought-prone area was located in the west of northeast China. Explanations for the spatiotemporal variations of the drought for soybean production were explored in terms of meteorological variables. Statistical analysis showed that the crop evapotranspiration, air temperature, wind speed, and number of sunshine hours were significantly higher and the precipitation and relative humidity were significantly lower in the drought-prone area than in the dry area less prone to droughts. An explored method of sensitive analysis quantitatively revealed that precipitation and humidity negatively affected the CWDI, whereas temperature, wind speed, and number of sunshine hours positively affected the CWDI. The CWDI was most sensitive to precipitation. These results not only provide valuable information for soybean planning and management but also produce important background and physical evidence for the influence of climate on the drought related to soybean production in northeast China.

Atmospheric concentrations of selected allergenic fungal spores in relation to some meteorological factors, in Timişoara (Romania)

Present investigation was undertaken to study the dynamics of relationships between atmospheric fungal spores and meteorological factors in western Romania. The airborne spore sampling was carried out by employing volumetric sampling. A total of nine meteorological parameters were selected for this investigation. During 2008–2010, it was found the same pattern of behaviour in the atmosphere for selected spore types (Alternaria, Cladosporium, Pithomyces, Epicoccum and Torula). The spores occurred in the air throughout the whole year, but maximum concentrations were reached in summer. Cladosporium and Alternaria peak levels were observed in June. Epicoccum peak value was found in September. The relationships between airborne spore concentrations and environmental factors were assessed using the analysis of Spearman’s rank correlations and multiple linear regressions. Spearman’s rank correlation analysis revealed that maximum, minimum and mean temperature, and number of sunshine hours were strongly (p < 0.01) and directly proportional to the concentration of all analysed fungal spores. Negative and significant correlations were with daily mean relative humidity. The variance explained percentage by regression analyses varied between 30.6 and 39.6 % for Alternaria and Cladosporium airborne spores. Statistical methods used in this study are complementary and confirmed stable dependence of Alternaria and Cladosporium spore concentrations on meteorological factors. The climate change parameters either increased temperatures, changed precipitation regimes or a combination of both affected allergenic fungal spore concentrations in western Romania. This study demonstrates the need for investigations throughout the year, from month to month, regarding the correct interpretation of airborne spore relationships with meteorological parameters.

Analysis of interannual variability of sunshine hours and precipitation over Peninsular Spain

Solar energy is one of the more abundant sources of renewable energy. It would be desirable that it is more stable over time than other energies with high interannual variability like hydropower. In this study we analyse the interannual variability of sunshine hours and precipitation over Spain, with the aim of comparing the reliability of solar energy to hydropower. An analysis in this respect has not been done before. We have used data from almost 100 stations in the WMO–AEMET (Spanish State Agency for Meteorology) network, and have applied two indices, the coefficient of variability (CV) and the speed of convergence, defined as the number of years of data needed to fully characterize a site. The main result is that the interannual variability for sunshine hours is several times lower than for precipitation over most of Spain, with the exception of the northern coast. The southwestern peninsular area stands out in this respect. This area is characterized at the same time by the highest number of sunshine hours, high speed of convergence and a low maximum departure of annual sunshine hours from the long-term mean. All this make this area optimal and very reliable for placing solar power plants.

The annual growth cycle of grapevines in Southern Finland

The aim of this study was to investigate whether grape growing is possible in the southernmost areas of Finland, in the Helsinki-Vantaa area (Tuusula parish, lat. 60°24ʹ10ʹʹN, long. 25°25ʹ45ʹʹE). The annual growing cycle of grapevines, with some climate parameters, was monitored over ten years (2002-2011). The growth cycle of grapevines from bud break to harvest was 138 (± 9) days, the growing season 198(±18) days, the temperature sum 1608 (± 131) °C days (GDD, basic + 5 °C) and 794 (± 121) °C days (basic +10 °C), the number of sunshine hours 1447 (± 117) h, and the solar energy 2904 (± 127) MJ/m². Dependence was calculated between some essential growth factors by statistical analyses. According to the results it can be concluded that, under existing weather conditions, grape growing is possible in southernmost Finland, although it will be necessary to find or further develop varieties adapted to the northern cool climate and to identify regions with an optimal microclimate for growing grapes.

Relationship between sunshine duration and air temperature and contemporary global warming

The purpose of this paper is to describe the variability of sunshine duration and air temperature and to assess the relationship between these variables. The paper is based on daily means of air temperature and daily sunshine duration totals from the 1884–2012 period. The variability analyses of these variables for the whole period is supplemented by additional trend analyses for two separate time periods described in the literature as dimming (1958–1985) and brightening (1985–2012). All the data come from the Jagiellonian University Research Station in Krakow. In Krakow, there is a decrease in the number of sunshine hours in the 1950s to 1980s period followed by an increase in the last two decades of the 20th century. The long-term course of air temperature in Krakow confirms the results obtained in other places in the world and exhibits increasing warming of the climate. The temperature increase is visible in each month but is highest in winter (exceeding 1.5 °C per 100 years). Therefore, it may be assumed that the increase in air temperature, which has been particularly strong since the 1980s, showed the full effect of global warming in the brightening period that was previously masked by global dimming as shown in the sunshine duration records. The time course of air temperature for the whole study period (1884–2012) shows a statistically significant positive linear trend. The present warming is influenced probably by the air-quality improvement (brightening period) and an increase in sunshine duration in the years 1980–2012.

Field dissipation of trifloxystrobin and its metabolite trifloxystrobin acid in soil and apples.

The dissipation of trifloxystrobin and its metabolite trifloxystrobin acid in apples and soil was studied, and the half-life (DT₅₀) was estimated in a field study carried out at three different locations for apples and four different locations for soil. Trifloxystrobin was sprayed on apples at 127 g a.i./ha for the dissipation study. Samples of apple and soil for the dissipation experiment were collected at time intervals of 0, 1, 3, 7, 14, 21, 30, and 45 days after treatment. The quantification of residues was done by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The DT₅₀ of trifloxystrobin ranged from 0.54 to 8.8 and 4.8 to 9.5 days in soil and apples at different latitude sites. Photolysis may be the main dissipation pathway for trifloxystrobin, and the number of sunshine hours may be the main factor affecting the trifloxystrobin dissipation rate in the field. For trifloxystrobin acid residues in soil and apples, it first increased and then began decreasing. It was indicated that the risk of trifloxystrobin application in shorter sunshine hour area should be considered.

Solar power potential mapping in India using remote sensing inputs and environmental parameters

The present paper maps the district-wise potential for concentrating solar power (CSP) and centralized solar photovoltaic (SPV) technology based power plants in India. The evaluation is based on remotely-sensed annual average global horizontal irradiance (GHI) and direct normal irradiance (DNI) provided by National Aeronautics and Space Administration (NASA) surface meteorology and solar energy program. The solar irradiation data (GHI and DNI), land-use data and Digital Elevation Model (DEM) were used in GIS environment while employing land-use criteria and topography to exclude unsuitable sites for harnessing solar energy. Furthermore, land-cover factor, number of sunshine hours and conversion efficiencies were taken into account to calculate technical potential in suitable land areas for solar power development. The result shows potential sites for installation of CSP and centralized large scale SPV plants in India.

Evaluation Seed-born Fungi of Rice [Oryza sativa L.] and that Effect on Seed Quality

Poor seedling establishment in rice is one of the problems in Guilan province as the second most important rice-growing locations in Iran. The aim of this study was to evaluate the contamination occurrence of rice seed in five locations of Guilan province to seed-borne fungi and their effects on germination characteristics. Five seed sample of Hashemi variety obtained from leading farmers from each location, and their germination characteristics and the rate of contamination to Fusarium moniliforme, Bipolaris oryzae, Aspergillus niger, A. flavus, Penicillium sp., Alternaria padwickii was evaluated using the PDA and standard blotter methods. The assessment results showed that among the seed-borne fungi, two species A. niger and A. flavus exhibited the highest severity in both methods. Samples from Rasht and Zeybaknar locations showed the most contamination to A. flavus and A. niger. A positive and significant linear relationship was observed between daily precipitation and relative humidity with severity of A. flavus and A. niger fungus. A. niger, A. padwickii, daily precipitation and average minimum temperature had the most influence on germination characteristics. Among the studied factors, A. niger had high negative impact compared to other factors on all rice seed germination characteristics. Among the study locations, quality of seeds in Rostam- Abad in terms of germination percentage, germination rate, germination uniformity and electrical conductivity had the best state. The results of this study showed that the low precipitation and low daily average humidity along with higher number of sunshine hours in the Rostam-Abad caused reduction in activity and abundance of fungi, led to improve the quality of produced seed.

Estimation of Monthly Mean Daily Global Solar Radiation over Bangkok, Thailand Using Artificial Neural Networks

Thailand is located in an equatorial belt that receives abundant solar energy. In order to achieve the optimum utilization of solar energy available, it is necessary to evaluate the incident solar radiation over the region of interest. Solar radiation can be assessed by means of measurements or mathematical modeling. Accurate measurements, using sophisticated and costly equipment, is available and has indeed been used extensively to assess solar radiation. This paper concentrates on an alternative approach to assess global solar radiation (GSR) by using Artificial Neural Networks (ANNs) together with classical observed meteorological data. The model is applied to the region of Bangkok, Thailand, using meteorological data, along with solar radiation measurements, for the period 2001-2010 from the Thai Meteorological Department (TMD). More precisely, three combinations of observed monthly mean meteorological data, i.e. maximum, minimum, and mean temperatures; relative humidity; rainfall amount; and sunshine hours were used with 3, 5 and 6 parameters as the model input for the ANN training to predict the solar radiation over the territory. A feed-forward back-propagation ANNs were trained based on three algorithms, i.e. the Quasi-Newton, the conjugate gradient with Polak-Ribiére updates and the Bayesian regularization. The root mean square error (RMSE) and the mean bias error (MBE) between the observed and the predicted solar radiations in 2011-2012 were computed in order to investigate the performance of the ANNs. Results showed that, for monthly mean number of sunshine hours in the range of 3.58 to 9.55 hr/day, the monthly mean GSR above the atmosphere of Bangkok was in the range of 5.64 to 22.53MJ/m2/day. The RMSE and the MBE were 0.0031 - 0.3632 and -0.0203 - 0.003, respectively, thus indicating that the ANN modeling has sufficient performance to predict the monthly mean GSR over an area where classical meteorological data are measured.

Stable carbon isotopes of glucose received from pine tree-rings as bioindicators of local industrial emission of CO2 in Niepołomice Forest (1950–2000)

The mass spectrometric investigations of carbon isotope composition of glucose received from α-cellulose samples derived from Scots pine (Pinus sylvestris L.) growing in Niepołomice Forest were the main aim of this study. The annual rings covered the time span from 1950 to 2000. α-Cellulose samples were extracted from increment cores of four representative trees, and then acid hydrolysis was performed. The number of sunshine hours, thermal and pluvial conditions of the growing season and in the preceding months had a significant effect on pine. Also non-climatic factors, most likely by industrial pollution signal, have been recorded in the isotopic composition of glucose. The relationship between climatic conditions, carbon dioxide emission and annual tree-rings carbon isotopic composition was analysed, using methods of correlation and response function, and multiple regression function.

Estimation of horizontal diffuse solar radiation from common meteorological parameters: a case study for Jeddah, Saudi Arabia

The measured data of global and diffuse solar radiation on a horizontal surface, number of sunshine hours, mean daily ambient temperature, maximum and minimum ambient temperatures, relative humidity and amount of cloud cover, for Jeddah (latitude 21° 42′ 37″ N, longitude 39° 11′ 12″ E), Saudi Arabia for the period (1996–2006) are analysed. The data are employed to develop empirical correlations between the monthly average daily diffuse fraction (H d /H) or diffuse transmittance (H d /H 0) and various meteorological parameters such as relative number of sunshine hours (s/s 0), ambient temperature T, relative humidity R h and amount of cloud cover c w. The derived correlations are evaluated by making comparisons between measured and calculated values of monthly average daily diffuse radiation H d. All the proposed correlations are found to be able to predict the monthly and annual averages daily diffuse radiation with excellent accuracy. It is also inferred that, if the data of the monthly average daily global radiation H and number of bright sunshine hours s are not available, the values of H d for the hot-humid zone of Saudi Arabia can be estimated with a reasonable accuracy from the correlations between H d /H 0 and the mean daily ambient temperature T.

Sea breezes at Cotonou and their interaction with the West African monsoon

5-year 3-hourly wind speed and direction, air temperature over land and sea surface temperature data are analysed in order to characterize sea breezes at Cotonou (Republic of Benin, West Africa). A set of criteria based on the diurnal reversal of wind direction, the thermal gradient and the number of sunshine hours is used to identify sea breeze days. Statistics are presented that describe the occurrence, duration and strength of the sea breezes. It is found that the sea breeze occurs during all seasons in this region. Sea breeze occurrence is found to be strongly influenced by the West African monsoon. The frequency of occurrence shows clearly two regimes characterized by two maxima (December and May). Sea breezes occur about half of the days during non-monsoon season (winter). Land/sea breezes onset and cessation times show a pronounced seasonal variation. Sea breeze strength is greater during the West African monsoon season. A hodograph analysis reveals the existence of both clockwise and anticlockwise rotation. Average hodographs show clearly the onshore–offshore nature of the sea breeze circulation, but have indeterminate rotation. There is a significant seasonal effect of large-scale flows on sea breeze hodograph patterns.

Serum BDNF concentrations show strong seasonal variation and correlations with the amount of ambient sunlight.

Earlier findings show seasonality in processes and behaviors such as brain plasticity and depression that in part are regulated by Brain-Derived Neurotrophic Factor (BDNF). Based on this we investigated seasonal variation in serum BDNF concentrations in 2,851 persons who took part in the Netherlands Study of Depression and Anxiety (NESDA). Analyses by month of sampling (monthly n’s >196) showed pronounced seasonal variation in serum BDNF concentrations (P<.0001) with increasing concentrations in the spring-summer period (standardized regression weight (ß) = 0.19, P<.0001) and decreasing concentrations in the autumn-winter period (ß = −0.17, P<.0001). Effect sizes [Cohen’s d] ranged from 0.27 to 0.66 for monthly significant differences. We found similar seasonal variation for both sexes and for persons with a DSM-IV depression diagnosis and healthy control subjects. In explorative analyses we found that the number of sunshine hours (a major trigger to entrain seasonality) in the week of blood withdrawal and the 10 weeks prior to this event positively correlated with serum BDNF concentrations (Pearson’s correlation coefficients ranged: 0.05 – 0.18) and this could partly explain the observed monthly variation. These results provide strong evidence that serum BDNF concentrations systematically vary over the year. This finding is important for our understanding of those factors that regulate BDNF expression and may provide novel avenues to understand seasonal dependent changes in behavior and illness such as depression. Finally, the findings reported here should be taken into account when designing and interpreting studies on BDNF.

Analysis of cyanobacteria bloom in the Waihai part of Dianchi Lake, China

Blue-green algae (BGA) bloom is a typical phenomenon in eutrophied lakes. However, up to now, no environmental mechanism has been commonly accepted. Systematic and complete data sets of BGA blooms and environmental factors without any missing data are rare, which seriously affected previous studies. In this study, a bootstrapping based multiple imputation algorithm (EMB) was first applied to reconstruct a complete data set from the available data set with missing data, hence forming a basis for quantitatively relating BGA bloom to contributing factors. Then, the probability of BGA bloom outbreak was simulated using a binomial (or binary) logistic regression model, which is an effective tool for recognizing key contributing factors. The results suggest that 1) the outbreak frequency or probability of BGA bloom tends to first increase and then decrease with a turning point between June and September each year; 2) air temperature, relative humidity, and precipitation were significant positive factors correlated with outbreak frequency, whereas wind speed and the number of sunshine hours were negative factors; 3) water temperature had a strong positive effect on the probability of BGA bloom outbreak, whereas other water quality factors, such as concentrations of organics and nutrients, were not so significant. However, water quality factors, such as NO3–N, SD, pH, NH4–N, COD and DO, still need to be concerned, which had a potential to aggravate the outbreak of BGA bloom in Dianchi Lake, if they were out of control.

History and state of solar engineering in Uzbekistan

The use of renewable energy sources (RES’s) is a topical problem for the Republic of Uzbekistan and stems from the need to guarantee the country’s energy security, as well as to improve the living and social con� ditions of its population. The main types of RES’s used in the country are solar (SE), hydraulic, wind, geothermal, and biomass energy. The country’s total technological potential in regard to the available RES’s is 179.4 million tons of oil equivalent (TOE), which is three times more than the annual national demand for energy resources [1]. The area of Uzbekistan is 447400 km 2 , and 70% of the land is occupied by deserts. The country is located in a region that is climatically favorable for using SE, i.e., 37°–45° north latitude and 56°–73° east longi� tude. The energy potential of SE is 98.5% of the total RES’s [1], and it is therefore considered to be a key factor that determines the extent of using RES’s in the general national power balance. The table below gives the results of processing long� term actinometric figures that indicate the annual influx of direct solar radiation Σq⊥ to the sunlight receptive surface in real weather conditions (i.e., cloudy days included) and actual annual number of sunshine hours n. These are the basic indicators of SE resources in the republic’s representative regions [2].

Cluster-based method for understanding the climactic diversity of Iran

The main purpose of this study is clustering Iran based on the components of the climate affecting the climate of Iran. For this study, 10 components of the climate: the mean temperature difference, the average minimum and maximum relative humidity, number of sunshine hours, monthly amounts of precipitation, days with precipitation higher than 5 and 10 mm, effective precipitation, average wind speed, frequency of occurrence of values ​​over 5 knots per second, number of frost days are used for a 26 year period from 1980 to 2005 and for 64 synoptic and climatological stations of the country. In the clustering process, the best clustering for Iran is introduction of Iran to four clusters into which appropriate weather stations in this clusters are distributed. Key words: Clustering, climatic variation, ward method, matrix, Iran.

Clustering the Iran climate based on climatic elements affecting potential evapotranspiration

The main purpose of this study is to cluster the Iran climate based on the components of the climate affecting evapotranspiration. For this study, eight components of the climate, the mean temperature difference, the average minimum and maximum relative humidity, number of sunshine hours, monthly amounts of precipitation, days with precipitation higher than 5 and 10 mm, effective precipitation, frequency of occurrence of values ​​over 5 knots per second are used for a 26-year period from 1980 to 2005 and for 64 synoptic and climatological stations of the country. In the clustering process, the best clustering for Iran has been six clusters into which weather stations are distributed appropriately. Key words: Iran, calibration, data, observations, potential evapotranspiration.

Effects of sunshine on suicide rates

ObjectivesSeasonal spring peaks of suicide are well described in epidemiological studies, but their origin is poorly understood. More recent evidence suggests that this peak may be associated with the increase in the duration of sunshine in spring. We investigated the effect of number of sunshine hours per month on suicide rates in Austria between 1996 and 2006. MethodsSuicide data, differentiated by month of suicide, sex, and method of suicide (violent vs nonviolent methods), were provided by Statistics Austria. Data on the average number of sunshine hours per month were calculated from 39 representative meteorological stations (provided by the Austrian Central Institute for Meteorology and Geodynamics). For statistical analysis, analysis of variance tests, Kruskal-Wallis tests, and Pearson correlation tests were used. ResultsA total of 16 673 suicides with a median of 126 ± 19.8 suicides per month occurred in the examined period. A clear seasonal pattern was observed, with suicide frequencies being highest between March and May and lowest between November and January (df = 11, F = 5.2, P < .0001) for men (df = 11, F = 4.9, P < .0001) and women (df = 11, F = 2.4, P = .008). The average number of sunshine hours per month was significantly correlated with the number of suicides among both sexes (r = .43, P < .0001), violent methods (r = .48, P < .0001) but not with nonviolent methods (r = .03, P = .707). ConclusionsThis study shows that seasonal changes in sunshine account for variations in the number of suicides and especially violent suicides. We propose that sunshine, via interactions with serotonin neurotransmission, may trigger increased impulsivity and promote suicidal acts. However, because of the hypothesis-generating design of this study, more research is needed to further clarify the role of sunshine in triggering neurobiologic changes, which might contribute to suicidal behavior.