Variation of incoming solar radiation flux during a partial eclipse episode: an improved model simulation

TL;DR

This paper presents an improved model to simulate the variation of solar radiation flux during a partial eclipse, enhancing accuracy with a simple approach based on celestial geometry.

Contribution

It introduces a novel, simplified method for estimating solar irradiance during partial eclipses using geometric parameters, extending previous models for total eclipses.

Findings

Estimated UV irradiance trend within ±5% of observations

Model effectively captures irradiance variation during the 2006 eclipse

Approach simplifies calculations while maintaining accuracy

Abstract

Model simulations of solar irradiance reaching the Earth's surface during a solar eclipse constitute a useful tool for studying the impact of this phenomenon on the radiance propagation through the atmosphere. A simple approach to extend the use of an algorithm already adopted for evaluating the variations in the extraterrestrial solar radiation during a total eclipse is proposed for a partial eclipse case. The application is based on the assessment of the distance between the apparent solar and lunar disk centers on the celestial hemisphere, using the local circumstances and the ratio between the Sun and Moon radii as input parameters. It was found that during the eclipse of March 29, 2006, the present approach led to an estimate of the surface UV solar irradiance trend differing by no more than \pm5% from the corresponding trend observed at Bologna (Italy).