An alternative formulation of the Langley plot relating observed solar irradiance, extraterrestrial solar irradiance, and air mass has been suggested to potentially improve radiometer calibration accuracy. In this study, results from the traditional and alternative plotting methods are compared using both simulated and measured data. The simulations indicate that their relative accuracies depen...

The performance data of a PV module are derived from the current-voltage characteristic measured under standard test conditions (STC). For this purpose, test laboratories as well as module production plants employ solar simulators which, depending on type and module size, display a more or less pronounced non-uniform distribution of irradiance in the test plane. In view of the quality assurance...

Reconstructions of total solar irradiance (TSI) rely mainly on linear relations between TSI variation and indices of facular area. When these are extrapolated to the prolonged 15th–17th century Spörer and Maunder solar activity minima, the estimated solar dimming is insufficient to explain the mid-millennial climate cooling of the Little Ice Age. We draw attention here to evidence that the rela...

The total solar irradiance (TSI) climate data record includes overlapping measurements from 10 spaceborne radiometers. The continuity of this climate data record is essential for detecting potential long-term solar fluctuations, as offsets between different instruments generally exceed the stated instrument uncertainties. The risk of loss of continuity in this nearly 30-year record drives the n...

Context. The solar irradiance in the UV is a key ingredient in space weather applications; however, because of the lack of continuous and long-term observations, various indices are still used today as surrogates for the solar spectral irradiance. Aims. As an alternative to current spectrometers we use a few radiometers with properly chosen passbands and reconstruct the solar spectral irradianc...

The variation of the solar irradiance over the solar cycle has a strong wavelength dependence, being larger at shorter wavelengths. Here we present simple models of the spectral dependence of irradiance variations between solar activity maximum and minimum. We find that the observations (which concentrate on the UV) cannot be reproduced by a change in effective temperature of the Sun (or of par...

Estimation method of aerosol parameter by means of solar direct and diffuse irradiance measurements with the proposed instrument of fiber-ball radiometer without sun tracking mechanics is proposed. Sky-radiometer and aureolemeter is well known instrument which allows measurements of solar direct and diffuse irradiance for estimation of aerosol parameter. The proposed fiber-ball radiometer also ...

This research describes the development and evaluation of the accuracy and precision of an Android app specifically designed, written and installed on a smartphone for detecting and quantifying incident solar UVA radiation and subsequently, aerosol optical depth at 340 and 380 nm. Earlier studies demonstrated that a smartphone image sensor can detect UVA radiation and the responsivity can be ca...