939 resultados para Weather
Resumo:
Prognostics concerning the day of the week on which kalendae ianuariae and Christmas Day fall, commonly known as the Revelatio Esdrae , purport to be a set of prophecies by the Biblical Esdras. They make predictions about the weather and other natural phenomena for the year to come, and they then extend their predictions to the field of human affairs. A remarkable number of copies of the Revelatio appear in English manuscripts from the tenth to the twelfth centuries. Some of these versions have been attributed to Bede and Abbo of Fleury as part of their computus works.
Both R. M. Liuzza and L. S. Chardonnens point out the frequent occurrence of the Revelatio in religious and scientific manuscripts and therefore reject the label of folklore, stressing instead the probable monastic origin of this prognostication. This study will provide the first complete collation and analysis of the surviving exemplars, to give as full an idea as possible of their circumstances of composition, their transmission, and their relationship to one another. It will consider how the Revelatio Esdrae was copied and used in Anglo-Saxon England, the audience to which it was addressed, and whether any conclusion can be drawn from its appearance in particular manuscripts, alongside certain other texts.
The regular occurrence of the Revelatio along with computistical material supports the case for its monastic origin and learned nature. Such a text would have been a helpful handbook to be used by monks and priests, and was among the standard holdings of continental and Anglo-Saxon monasteries and scriptoria, giving further proof of the monks’ intellectual eclecticism and their knowledge of the kinds of continental literature from which this text derives.
Resumo:
Recent cold winters and prolonged periods of low wind speeds have prompted concerns about the increasing penetration of wind generation in the Irish and other northern European power systems. On the combined Republic of Ireland and Northern Ireland system there was in excess of 1.5 GW of installed wind power in January 2010. As the penetration of these variable, non-dispatchable generators increases, power systems are becoming more sensitive to weather events on the supply side as well as on the demand side. In the temperate climate of Ireland, sensitivity of supply to weather is mainly due to wind variability while demand sensitivity is driven by space heating or cooling loads. The interplay of these two weather-driven effects is of particular concern if demand spikes driven by low temperatures coincide with periods of low winds. In December 2009 and January 2010 Ireland experienced a prolonged spell of unusually cold conditions. During much of this time, wind generation output was low due to low wind speeds. The impacts of this event are presented as a case study of the effects of weather extremes on power systems with high penetrations of variable renewable generation.
Resumo:
Seasonal and day-to-day variations in travel behaviour and performance of private passenger vehicles can be partially explained by changes in weather conditions. Likewise, in the electricity sector, weather affects energy demand. The impact of weather conditions on private passenger vehicle performance, usership statistics and travel behaviour has been studied for conventional, internal combustion engine, vehicles. Similarly, weather-driven variability in electricity demand and generation has been investigated widely. The aim of these analyses in both sectors is to improve energy efficiency, reduce consumption in peak hours and reduce greenhouse gas emissions. However, the potential effects of seasonal weather variations on electric vehicle usage have not yet been investigated. In Ireland the government has set a target requiring 10% of all vehicles in the transport fleet to be powered by electricity by 2020 to meet part of its European Union obligations to reduce greenhouse gas emissions and increase energy efficiency. This paper fills this knowledge gap by compiling some of the published information available for internal combustion engine vehicles and applying the lessons learned and results to electric vehicles with an analysis of historical weather data in Ireland and electricity market data in a number of what-if scenarios. Areas particularly impacted by weather conditions are battery performance, energy consumption and choice of transportation mode by private individuals.
Resumo:
Recent epidemics of acute asthma have caused speculation that, if their causes were known, early warnings might be feasible. In particular, some epidemics seemed to be associated with thunderstorms. We wondered what risk factors predicting epidemics could be identified. Daily asthma admissions counts during 1987-1994, for two age groups (0-14 yrs and > or = 15 yrs), were measured using the Hospital Episodes System (HES). Epidemics were defined as combinations of date, age group and English Regional Health Authority (RHA) with exceptionally high asthma admission counts compared to the predictions of a log-linear autoregression model. They were compared with control days 1 week before and afterwards, regarding seven meteorological variables and 5 day average pollen counts for four species. Fifty six asthma epidemics were identified. The mean density of sferics (lightning flashes), temperature and rainfall on epidemic days were greater than those on control days. High sferics densities were overrepresented in epidemics. Simultaneously high sferics and grass pollen further increased the probability of an epidemic, but only to 15% (95% confidence interval 2-45%). Two thirds of epidemics were not preceded by thunderstorms. Thunderstorms and high grass pollen levels precede asthma epidemics more often than expected by chance. However, most epidemics are not associated with thunderstorms or unusual weather conditions, and most thunderstorms, even following high grass pollen levels, do not precede epidemics. An early warning system based on the indicators examined here would, therefore, detect few epidemics and generate an unacceptably high rate of false alarms.
Resumo:
The impact of climate change on fungal growth and spore production is less well documented than for allergenic pollen grains, although similar implications for respiratory tract diseases in humans occur. Fungal spores are commonly described as either “dry” or “wet” according to the type of weather associated with their occurrence in the air. This study examined the distribution of selected fungal spores (Alternaria spp., Cladosporium spp., Didymella spp., Epicoccum spp., Leptosphaeria spp. and rusts) occurring in the West Midlands of UK during 2 years of contrasting weather. Spore specimens were collected using a 7-day volumetric air sampler and then analysed with the aid of light microscopy. Distributions of spores were then studied using normality tests and Mann–Whitney U test, while relationships with meteorological parameters were investigated using Spearman’s rank test and angular-linear correlation for wind direction analysis. Our results showed that so-called wet spores were more sensitive to the weather changes showing statistically significant differences between the 2 years of study, in contrast to “dry” spores. We predict that in following years we will observe accelerated levels in allergenic fungal spore production as well as changes in species diversity. This study could be a starting point to revise the grouping system of fungal spores as either “dry” or “wet” types and their response to climate change
Resumo:
This paper examines to what extent individual measures of well-being are correlated with daily weather patterns in the United Kingdom. Merging daily weather data with data from the British Household Panel Survey (BHPS) allows us to test whether measures of well-being are correlated with temperature, sunshine, rainfall and wind speed. We are able to make a strong case for causality due to ‘randomness’ of weather in addition to using regression methods that eliminate time-invariant individual level heterogeneity. Results suggest that some weather parameters (such as sunshine) are correlated with some measures of well-being (job satisfaction); however, in general the effect of weather on subjective measures of well-being is very small.