Sunshine duration data in San Fernando (South of Spain) during 1880s: The impact of Krakatoa volcanic eruption

The evaporation losses are very high in warm-arid regions and their accurate evaluation is vital for the sustainable management of water resources. The assessment of such losses involves extremely difficult and original tasks because of the scarcity of data in countries with an arid climate. The main objective of this paper is to develop models for the simulation of pan-evaporation with the help of Penman and Hamon’s equations, Artificial Neural Networks (ANNs), and the Artificial Neuro Fuzzy Inference System (ANFIS). The results from five types of ANN models with different training functions were compared to find the best possible training function. The impact of using various input variables was investigated as an original contribution of this research. The average temperature and mean wind speed were found to be the most influential parameters. The estimation of parameters for Penman and Hamon’s equations was quite a daunting task. These parameters were estimated using a state of the art optimization algorithm, namely General Reduced Gradient Technique. The results of the Penman and Hamon’s equations, ANN, and ANFIS were compared. Thirty-eight years (from 1980 to 2018) of manually recorded pan-evaporation data regarding mean daily values of a month, including the relative humidity, wind speed, sunshine duration, and temperature, were collected from three gauging stations situated in Al Qassim, Saudi Arabia. The Nash and Sutcliffe Efficiency (NSE) and Mean Square Error (MSE) evaluated the performance of pan-evaporation modeling techniques. The study shows that the ANFIS simulation results were better than those of ANN and Penman and Hamon’s equations. The findings of the present research will help managers, engineers, and decision makers to sustainability manage natural water resources in warm-arid regions.

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Testing the spatial applicability of the Johnson–Woodward method for estimating solar radiation from sunshine duration data

Agricultural and Forest Meteorology ◽

10.1016/j.agrformet.2007.10.008 ◽

2008 ◽

Vol 148 (3) ◽

pp. 466-480 ◽

Cited By ~ 14

Author(s):

D.G. Miller ◽

M. Rivington ◽

K.B. Matthews ◽

K. Buchan ◽

G. Bellocchi

Keyword(s):

Solar Radiation ◽

Sunshine Duration ◽

Duration Data

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Heterogeneity in norovirus shedding duration affects community risk

Epidemiology and Infection ◽

10.1017/s0950268813000496 ◽

2013 ◽

Vol 141 (8) ◽

pp. 1572-1584 ◽

Cited By ~ 23

Author(s):

M. O. MILBRATH ◽

I. H. SPICKNALL ◽

J. L. ZELNER ◽

C. L. MOE ◽

J. N. S. EISENBERG

Keyword(s):

Attack Rate ◽

Transmission Model ◽

Reproductive Number ◽

Risk Models ◽

Common Cause ◽

Viral Shedding ◽

Duration Data ◽

Community Risk ◽

Community Transmission ◽

The Impact

SUMMARYNorovirus is a common cause of gastroenteritis in all ages. Typical infections cause viral shedding periods of days to weeks, but some individuals can shed for months or years. Most norovirus risk models do not include these long-shedding individuals, and may therefore underestimate risk. We reviewed the literature for norovirus-shedding duration data and stratified these data into two distributions: regular shedding (mean 14–16 days) and long shedding (mean 105–136 days). These distributions were used to inform a norovirus transmission model that predicts the impact of long shedders. Our transmission model predicts that this subpopulation increases the outbreak potential (measured by the reproductive number) by 50–80%, the probability of an outbreak by 33%, the severity of transmission (measured by the attack rate) by 20%, and transmission duration by 100%. Characterizing and understanding shedding duration heterogeneity can provide insights into community transmission that can be useful in mitigating norovirus risk.

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Volcanic impact on the tropical hydrological cycle

10.5194/egusphere-egu21-15234 ◽

2021 ◽

Author(s):

Roberta D'Agostino ◽

Claudia Timmreck

Keyword(s):

Volcanic Eruption ◽

Hydrological Cycle ◽

Wide Spectrum ◽

Volcanic Eruptions ◽

Internal Variability ◽

Net Energy ◽

Max Planck ◽

Monsoon Area ◽

Volcanic Forcing ◽

The Impact

The impact of volcanic forcing on tropical precipitation is investigated in a new set of sensitivity experiments within Max Planck Institute Grand Ensemble framework. Five ensembles are created, each containing 100 realizations for an idealized tropical volcanic eruption located at the equator, analogous the Mt. Pinatubo eruption, with emissions covering a range of 2.5 - 40 Tg S. The ensembles provide an excellent database to disentangle the influence of volcanic forcing on regional monsoons and tropical hydroclimate over the wide spectrum of the climate internal variability. Monsoons are generally weaker during the two years after volcanic eruptions and their weakening is a function of emissions: the strongest the volcanic eruption, the weakest are the land monsoons. The extent of rain belt is also affected: the monsoon area is overall narrower than the unperturbed control simulation. While the position of main ascents does not change, the idealised tropical volcanic eruption supports the shrinking of Hadley Cell's ascent and the narrowing of the ITCZ. We investigate this behavior by analysing the changes in Hadley/Walker circulation, net energy input and energy budget to find analogies/differences with global warming.

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A Comparative Analysis of Sunshine Duration Effects in terms of Renewable Energy Production Rates on The LEED BD + C Projects in Turkey

Energies ◽

10.3390/en12061116 ◽

2019 ◽

Vol 12 (6) ◽

pp. 1116 ◽

Cited By ~ 1

Author(s):

Aynur Kazaz ◽

Seyda Adiguzel Istil

Keyword(s):

Global Warming ◽

Renewable Energy ◽

Construction Projects ◽

Energy Production ◽

Sunshine Duration ◽

Electricity Consumption ◽

Production Rates ◽

Certification System ◽

Renewable Energy Production ◽

The Impact

Global warming has been on the agenda over the past few years. Solutions to global warming and energy efficiency problems have brought with them the need for green building market. Leadership in Energy and Environmental Design (LEED) is a certification system regulating the compliance of green buildings to certain standards and is essential for construction projects focusing on sustainability and innovation. This study investigates the effects of sunshine duration on construction projects reducing annual electricity consumption and increasing renewable energy production. In this study, the effects of sunshine duration times on construction projects are located in different cities in Turkey which has gained point from LEED BD+C (NC) (LEED, Building Design + Construction: New Construction) certificate were analyzed with the help of getting the impact of annual electricity consumption and renewable energy production rates. It was our aim that the results will be used for construction projects in compliance with the “Energy and Atmosphere” category of the LEED BD+C certification system.

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Lag Variables in Nitrogen Oxide Concentration Modelling: A Case Study in Wrocław, Poland

Atmosphere ◽

10.3390/atmos11121293 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1293

Author(s):

Joanna A. Kamińska ◽

Fernando Jiménez ◽

Estrella Lucena-Sánchez ◽

Guido Sciavicco ◽

Tomasz Turek

Keyword(s):

Air Quality ◽

Wind Speed ◽

Traffic Flow ◽

Sunshine Duration ◽

Delayed Effect ◽

Hourly Data ◽

Random Forest Models ◽

Flow Intensity ◽

Lag Variables ◽

The Impact

Due to the unwavering interest of both residents and authorities in the air quality of urban agglomerations, we pose the following question in this paper: What impact do current and past meteorological factors and traffic flow intensity have on air quality? What is the impact of lagged variables on the fit of an explanation model, and how do they affect its ability to predict? We focused on NO2 and NOx concentrations, and conducted this research using hourly data from the city of Wrocław (western Poland) from 2015 to 2017; we used multi-objective optimization to determine the optimal delays. It turned out that for both NO2 and NOx, the past values for traffic flow, wind speed, and sunshine duration are more important than the current ones. We built random forest models on each of the pollutants for both the current and past values and discovered that including a lagged variable increases the resulting R2 from 0.51 to 0.56 for NO2 and from 0.46 to 0.52 for NOx. We also analyzed the feature importance in each model, and found that for NO2, a wind speed delay of more than three hours causes a significant decrease, while the importance of relative humidity increases with a seven-hour delay; likewise, wind speed increases the importance for NOx prediction with a two-hour delay. We concluded that, in pollutant concentration modeling, the possibility of a delayed effect of the independent variables should always be considered, because it can significantly increase the performance of the model and suggest unexpected relationships or dependencies.

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Siberian tree-ring and stable isotope proxies as indicators of temperature and moisture changes after major stratospheric volcanic eruptions

Climate of the Past ◽

10.5194/cp-15-685-2019 ◽

2019 ◽

Vol 15 (2) ◽

pp. 685-700 ◽

Cited By ~ 7

Author(s):

Olga V. Churakova (Sidorova) ◽

Marina V. Fonti ◽

Matthias Saurer ◽

Sébastien Guillet ◽

Christophe Corona ◽

...

Keyword(s):

Tree Ring ◽

Global Climate ◽

Sunshine Duration ◽

Ring Width ◽

Volcanic Eruptions ◽

Climate Dynamics ◽

Global Climate Models ◽

Added Value ◽

Latewood Density ◽

The Impact

Abstract. Stratospheric volcanic eruptions have far-reaching impacts on global climate and society. Tree rings can provide valuable climatic information on these impacts across different spatial and temporal scales. To detect temperature and hydroclimatic changes after strong stratospheric Common Era (CE) volcanic eruptions for the last 1500 years (535 CE unknown, 540 CE unknown, 1257 CE Samalas, 1640 CE Parker, 1815 CE Tambora, and 1991 CE Pinatubo), we measured and analyzed tree-ring width (TRW), maximum latewood density (MXD), cell wall thickness (CWT), and δ13C and δ18O in tree-ring cellulose chronologies of climate-sensitive larch trees from three different Siberian regions (northeastern Yakutia – YAK, eastern Taimyr – TAY, and Russian Altai – ALT). All tree-ring proxies proved to encode a significant and specific climatic signal of the growing season. Our findings suggest that TRW, MXD, and CWT show strong negative summer air temperature anomalies in 536, 541–542, and 1258–1259 at all studied regions. Based on δ13C, 536 was extremely humid at YAK, as was 537–538 in TAY. No extreme hydroclimatic anomalies occurred in Siberia after the volcanic eruptions in 1640, 1815, and 1991, except for 1817 at ALT. The signal stored in δ18O indicated significantly lower summer sunshine duration in 542 and 1258–1259 at YAK and 536 at ALT. Our results show that trees growing at YAK and ALT mainly responded the first year after the eruptions, whereas at TAY, the growth response occurred after 2 years. The fact that differences exist in climate responses to volcanic eruptions – both in space and time – underlines the added value of a multiple tree-ring proxy assessment. As such, the various indicators used clearly help to provide a more realistic picture of the impact of volcanic eruption on past climate dynamics, which is fundamental for an improved understanding of climate dynamics, but also for the validation of global climate models.

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Risk Analysis of Air Pollution and Meteorological Factors Affecting the Incidence of Diabetes in the Elderly Population in Northern China

Journal of Diabetes Research ◽

10.1155/2020/3673980 ◽

2020 ◽

Vol 2020 ◽

pp. 1-20

Author(s):

Yao Lin ◽

Saijun Zhou ◽

Hongyan Liu ◽

Zhuang Cui ◽

Fang Hou ◽

...

Keyword(s):

Air Pollution ◽

Meteorological Factors ◽

Sunshine Duration ◽

Additive Model ◽

Northern China ◽

The Elderly ◽

The United States ◽

Diabetes Incidence ◽

Lag Effects ◽

The Impact

Background. Research investigating the effect of air pollution on diabetes incidence is mostly conducted in Europe and the United States and often produces conflicting results. The link between meteorological factors and diabetes incidence remains to be explored. We aimed to explore associations between air pollution and diabetes incidence and to estimate the nonlinear and lag effects of meteorological factors on diabetes incidence. Methods. Our study included 19,000 people aged ≥60 years from the Binhai New District without diabetes at baseline. The generalized additive model (GAM) and the distributed lag nonlinear model (DLNM) were used to explore the effect of air pollutants and meteorological factors on the incidence of diabetes. In the model combining the GAM and DLNM, the impact of each factor (delayed by 30 days) was first observed separately to select statistically significant factors, which were then incorporated into the final multivariate model. The association between air pollution and the incidence of diabetes was assessed in subgroups based on age, sex, and body mass index (BMI). Results. We found that cumulative RRs for diabetes incidence were 1.026 (1.011-1.040), 1.019 (1.012-1.026), and 1.051 (1.019-1.083) per 10 μg/m3 increase in PM2.5, PM10, and NO2, respectively, as well as 1.156 (1.058-1.264) per 1 mg/m3 increase in CO in a single-pollutant model. Increased temperature, excessive humidity or dryness, and shortened sunshine duration were positively correlated with the incidence of diabetes in single-factor models. After adjusting for temperature, humidity, and sunshine, the risk of diabetes increased by 9.2% (95% confidence interval (CI):2.1%-16.8%) per 10 μg/m3 increase in PM2.5. We also found that women, the elderly (≥75 years), and obese subjects were more susceptible to the effect of PM2.5. Conclusion. Our data suggest that PM2.5 is positively correlated with the incidence of diabetes in the elderly, and the relationship between various meteorological factors and diabetes in the elderly is nonlinear.

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Impact of the 536/540 CE double volcanic eruption event on the 6th-7th century climate using model and proxy data

10.5194/egusphere-egu2020-19943 ◽

2020 ◽

Author(s):

Evelien van Dijk ◽

Claudia Timmreck ◽

Johann Jungclaus ◽

Stephan Lorenz ◽

Manon Bajard ◽

...

Keyword(s):

Tree Ring ◽

Volcanic Eruption ◽

Detailed Comparison ◽

Arctic Sea Ice ◽

Special Focus ◽

Decadal Climate Variability ◽

Proxy Data ◽

Tree Ring Data ◽

Volcanic Forcing ◽

The Impact

The mid of the 6th century is an outstanding period and started with an unusual cold period that lasted several years to decades, due to the 536/540 CE double eruption event, with the strongest decadal volcanic forcing in the last 2000 years. Evidence from multiple tree ring records from the Alps to the Altai Mountains in Russia identified a centennial cooling lasting from 536 up to 660 CE. A previous Earth System Model (ESM) study with reconstructed volcanic forcing covering 535-550 CE like conditions already found that the double eruption led to a global decrease in temperature and an increase in Arctic sea-ice for at least a decade. However, the simulations were too short to fully investigate the multi-decadal cooling event and the atmospheric forcing from this double volcanic eruption alone may not be enough to sustain such a prolonged cooling. To better understand forced versus internal decadal climate variability in the first millennium we have performed mid 6th century ensemble simulations with the MPI-ESM1.2 for the 520-680 CE period. The ensemble consists of 10 realizations, which were branched of the MPI-ESM1.2 PMIP4 Past2k run, including the evolv2k volcanic forcing.Here, we present results of this new set of the 6th-7th century MPI-ESM simulations in comparison to paleo-proxies. Summer surface temperatures are analyzed and compared with available tree-ring data, which fits very well for the entire 160 year period. As part of the VIKINGS project, special focus is placed on the impact of the 536/540 CE double volcanic eruption event on the surface climate in the Northern Hemisphere, in particular Scandinavia, Northern Europe and Siberia. The goal is to also compare the model data with new tree-ring and lake sediment proxies from southeastern Norway. Detailed comparison with proxy data will allow us to better understand the regional and seasonal climate variations of the 6th-7th century. Duration, strength and the possible mechanism for a long lasting volcanic induced cooling will be discussed.

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Global Atmospheric Evaporative Demand over Land from 1973 to 2008

Journal of Climate ◽

10.1175/jcli-d-11-00492.1 ◽

2012 ◽

Vol 25 (23) ◽

pp. 8353-8361 ◽

Cited By ~ 56

Author(s):

Kaicun Wang ◽

Robert E. Dickinson ◽

Shunlin Liang

Keyword(s):

Sunshine Duration ◽

Water Vapor Pressure ◽

Evaporative Demand ◽

Term Trend ◽

Direct Measurements ◽

Arid And Semiarid Areas ◽

Water Vapor Pressure Deficit ◽

The Impact ◽

Long Term Trend

Abstract Pan evaporation (EP), an index of atmospheric evaporative demand, has been widely reported to have weakened in the past decades. However, its interpretation remains controversial because EP observations are not globally available and observations of one of its key controls, surface incident solar radiation Rs, are even less available. Using global-distributed Rs from both direct measurements (available through the Global Energy Balance Archive) and derived from sunshine duration, the authors calculated the potential evaporation from 1982 to 2008 from approximately 1300 stations. The findings herein show that the contribution of water vapor pressure deficit (VPD) to monthly variability of EP is much larger than that of other controlling factors, of Rs, wind speed (WS), and air temperature Ta. The trend of the aerodynamic component of EP, which includes contributions of VPD, WS, and Ta, accounted for 86% of the long-term trend of EP. The aerodynamic component was then calculated from 4250 globally distributed stations and showed a negligible averaged trend from 1973 to 2008 because the reduction in WS canceled out the impact of the elevated VPD. The long-term trend of WS dominates the long-term trend of the aerodynamic component of EP at the 4250 stations. Atmospheric evaporative demand increased in most arid and semiarid areas, indicating a decrease in water availability in those areas.

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