I am a PhD student in the Centre for Atmospheric Science, using high resolution mass spectrometry (MS) to analyse the molecular composition of organic aerosol. My research involves using a novel, online, soft ionisation technique known as Extractive Electrospray Ionisation (EESI-MS) to measure aerosol ageing in real time and also using ultra-high resolution mass spectrometry (UHR-MS) to investigate the detailed molecular composition of rainwater and organic compounds in aerosol collected during a field campaign.