Designer ice nuclei for geoengineering of clouds

The collective international failure to curb rises in greenhouse gas emissions means we need to consider back up plans to avoid the worst potential impacts of climate change. A number of geoengineering schemes have been put forward and one of these involves modifying cirrus ice clouds. Thin cirrus clouds have a net warming effect on the planet, but by seeding them with efficient ice nuclei their global coverage could be reduced thus resulting in a cooling of the planet. Research is urgently needed into the basic science that will underpin schemes such as this. We propose a laboratory experimental study to identify materials which could be used to efficiently, safely and cost effectively nucleate ice (ice nuclei) in any future cloud geoengineering projects. Our strategy is to build on the experience and expertise at Asymptote Ltd who are experts in ice nucleation in the field of cryopreservation of biological samples. We already have an established working relationship with Asymptote and have published with them on freezing of water in jet fuel (see Murray's supervisor section for details). Our goal is to develop a fundamental understanding of ice nucleation by porous materials and use this to design ice nuclei which would be ideal for a range of applications. The primary focus of the student will be to identify ice nuclei for geoengineering purposes with potential benefits for society, whereas Asymptote Ltd will apply the same fundamental information to the commercial area of cryopreservation. We will therefore achieve both societal and economic impact with this work. Asymptote Ltd were recently awarded funds from the Technology Strategy Board to identifying ice nuclei which might be used in cryopreservation. This same experimental set up at Asymptote's laboratories will be used by the CASE student to screen a range of porous materials for their ice nucleating ability guided by a new theory of ice nucleation. We will then bring those same samples back to Leeds where we can quantify their ice nucleation efficiency under atmospherically relevant conditions. As well as working in a university research environment the CASE student will also spent a total of 6 months working at Asymptote Ltd. This will provide an opportunity to experience a commercial research environment and will learn skills that the School of Earth and Environment cannot offer such as management of intellectual property and the importance of commercial confidentiality. This combined with training in the fundamentals of nucleation and crystallisation as well as the transferrable skills training all Leeds students receive will give this individual a very competitive portfolio.