Solar cycles reflected in the English climate

We show that patternsof variationsin the central England temperature since 1660 asw ell asrainfall in England and Waless ince 1726 contain dominant oscillations and switching sequences at the periods of some sunspot cycles. These particular sunspot cycles are: the 80–90 year sunspot cycle, the 22-year sunspot cycle, and the 11-year sunspot cycle. In particular, the variation patterns are switched from one form into another form at a switching period of 80–90 years. Solar cycles of relatively larger periodicities are also dominantly reflected in southeast Scotland temperature recordss ince 1125 A.D. and in California temperature recordss ince 3431 B.C. We also show that some large and rapid changes in central England and California temperature variations are associated with solar activity

A generalized theory of sun-climate/weather link and climatic change

SIGLEITItal

Distortions in the output signals of conventional spectrum anlyzers

SIGLEITItal

The physical and theoretical basis of solar-terrestrial relationships. 1. Equatorial locations

SIGLEITItal

The physical and theoretical basis of solar-terrestrial relationships. 2. Non-equatorial locations

SIGLEITItal

Distortions caused by the signal processing in analog AM modulators

SIGLEITItal

Development and evaluation of neural network models to estimate daily solar radiation at Córdoba, Argentina Desenvolvimento e avaliação de modelos de redes neurais para estimação da irradiação solar diária em Córdoba, Argentina

The objective of this work was to develop neural network models of backpropagation type to estimate solar radiation based on extraterrestrial radiation data, daily temperature range, precipitation, cloudiness and relative sunshine duration. Data from Córdoba, Argentina, were used for development and validation. The behaviour and adjustment between values observed and estimates obtained by neural networks for different combinations of input were assessed. These estimations showed root mean square error between 3.15 and 3.88 MJ m-2 d-1 . The latter corresponds to the model that calculates radiation using only precipitation and daily temperature range. In all models, results show good adjustment to seasonal solar radiation. These results allow inferring the adequate performance and pertinence of this methodology to estimate complex phenomena, such as solar radiation.<br>O objetivo deste trabalho foi desenvolver modelos de redes neuronais, do tipo retropropagação, para a estimação da irradiação solar, a partir de dados de irradiação solar extraterrestre, amplitude térmica, precipitação, nebulosidade e razão de insolação. O treinamento e a validação foram realizados com dados correspondentes a Córdoba, Argentina. O comportamento e ajuste entre os valores observados e os estimados pelas redes foram avaliados para diferentes combinações das variáveis de entrada, que apresentaram valores do erro quadrático médio entre 3,15 e 3,88 MJ m-2 d-1 . Este último valor corresponde ao modelo que calcula a irradiação somente utilizando precipitação e amplitude térmica diária. Os resultados exibem em todos os modelos um ajuste apropriado ao comportamento sazonal da irradiação solar e permitem concluir a pertinência e o adequado desempenho desse método para estimar fenômenos complexos como a irradiação solar