Towards the Remote Sensing of Electric Fields in the Atmosphere

In this presentation we describe a proof-of-concept study on the possibility of detecting high electric fields in the atmosphere  e.g. around thunderstorms, using remote sensing techniques.  Current methods to measure electric field profiles through the atmosphere rely on radiosondes or aircraft operating in conditions where the instrument is prone to damage or give unreliable results.   We are investigating the feasibility of an alternative approach, which exploits the sensitivity of certain molecules to their electrical environment through the so-called Stark effect, whereby certain spectral lines are shifted in response to an external electric field.   This has the potential for the measurement of high electric fields above thunderstorms, although it does present a number of challenges .   In our study, we have been using radiative transfer models to simulate the effect of electric fields (such as are typically found around thunderstorm clouds)  on atmospheric spectra, looking in particular at THz wavelengths and focusing on selected candidate spectral lines of HDO.    Here, we will present our latest results.