School of Chemistry

Scientific cruise

Researchers in Chemistry have recently returned from South East Asia having participated in an international field project called SHIVA (Stratospheric ozone: Halogen Impacts in a Varying Atmosphere) which aims to understand the influence of emissions of halogen molecules from the oceans on the chemistry of the atmosphere.

Dr. Trevor Ingham (NCAS Fellow) and Hannah Bunyan (3rd year PhD student), who are both members of Professor Dwayne Heard's group, lived and worked aboard the RV Sonne, a German research vessel, for two weeks during a scientific cruise from Singapore to Manila. Training in the event of a pirate attack was mandatory, but fortunately was not required!

Trevor and Hannah made measurements of short lived iodine species (for example the iodine oxide radical) using laser-based instrumentation that was housed in a container at the very front of the ship. SHIVA is an EU funded project, coordinated by the University of Heidelberg, and involved partners from the UK, Malaysia, Germany, France, Norway and Belgium. Funding also came from the National Centre for Atmospheric Science, a NERC facility which is coordinated in Leeds. Professor Martyn Chipperfield and Ryan Hossaini, from the School of Earth and Environment at Leeds, are also involved in SHIVA and are performing a number of modeling studies.

This part of the world was chosen as emissions from the ocean surface can be rapidly uplifted (for example by convective storms) to very high altitudes and enter the stratosphere. Other partners made measurements of a range of molecules from a research aircraft in the same region. The data recorded from the cruise will help us to understand the chemical mechanisms which release iodinated species from the very upper layers of the ocean, or from aerosols generated by ocean waves, which are currently not well understood. Once in the atmosphere, these species can be broken down by sunlight, generating radicals which can react with ozone (an important greenhouse gas) in the immediate vicinity, and on a wider scale via vertical transport of longer-lived halogen species which can enter the stratosphere, and impact stratospheric ozone, which protects us from ultraviolet radiation. The project involved a lot of logistical planning, with the equipment still en route back from Manila. Further information about the SHIVA project can be found at: http://shiva.iup.uni-heidelberg.de/