Finding the best proxies for the solar UV irradiance

TL;DR

This paper evaluates nine solar proxies to determine which best replicate solar UV spectral variability across different time scales, using a novel multiscale statistical approach on data from 2003-2008.

Contribution

It introduces a new multiscale statistical method to compare solar proxies' effectiveness at different spectral bands and time scales.

Findings

Identifies the most suitable proxies for specific spectral bands.

Reveals proxies' varying performance across time scales.

Provides a comprehensive comparison framework for solar UV proxies.

Abstract

Solar UV emission has a profound impact on the upper terrestrial atmosphere. Because of instrumental constraints, however, solar proxies often need to be used as substitutes for the solar spectral variability. Finding proxies that properly reproduce specific spectral bands or lines is an ongoing problem. Using daily observations from 2003 to 2008 and a multiscale statistical approach, we test the performances of 9 proxies for the UV solar flux. Their relevance is evaluated at different time-scales and a novel representation allows all quantities to be compared simultaneously. This representation reveals which proxies are most appropriate for different spectral bands and for different time scales.