(SHIVA - Stratospheric Ozone: Halogen Impacts in a Varying Atmosphere; EU-project)
- cruise management Dr. Birgit Quack (RD2: Marine biogeochemics, chemical oceanography)
- ship proposal Dr. Birgit Quack and http://typoserv.ifm-geomar.de/index.php?id=kkrueger&L=1Dr. Kirstin Krüger (RD1: Ocean circulation and climate dynamics, marine meteorology)
It is now well known that certain ozone depleting substances (ODSs) are broken down by solar radiation in the stratosphere, releasing the halogen elements: chlorine, bromine and iodine. The halogens are highly efficient at destroying ozone in the stratosphere, and rising concentrations from human activities has led to depletion of global stratospheric ozone over the last three decades, and formation of the Antarctic “ozone hole”. It is also known that ODSs enter the stratosphere principally in the tropics, where ascending warm air carries them aloft. SHIVA aims to reduce uncertainties in the amount of halogen-containing ODSs reaching the stratosphere, and the resulting ozone depletion, in a climate that is changing now, and which will change in the future. Climate feedbacks between the emissions and transport of ODSs exist, particularly in the tropics where even short-lived ODSs of natural origin (e.g. emitted by the oceans, and by marine and terrestrial organisms) can enter the stratosphere in powerful deep convective systems. By combining measurements from land, ship, aircraft, and space-based platforms, with sophisticated numerical models, SHIVA aims to better predict the rate, timing and climate-sensitivity of ozone-layer recovery, and identify potential risks to that recovery.