Our lack of knowledge of how clouds will respond to a changing climate represent one of the largest sources of uncertainty in our projections of future climate (Tan et al., 2016). A major source of this uncertainty is related to special aerosol particles, known as ice-nucleating particles (INPs) which are needed to trigger ice formation in clouds. Once ice crystals form a cascade of processes triggers precipitation and leads to dramatic changes in cloud coverage and cloud reflectivity. However, the sources, characteristics and distribution around the globe of atmospheric ice nucleating particles is extremely poorly understood. In part, this is due to our lack of instrumentation capable of making the necessary measurements of INP and our ability to identify the aerosol particle types which nucleate ice.
To tackle this problem we have developed a microfluidic system which generates 100s of droplets a second in a channel and flows them over a cold plate and counts the fraction that freeze. In a further development we can now separate frozen from unfrozen droplets for off chip analysis which in principle allows us to analyse the composition and properties of ice nucleating particles. This system offers high throughput with extremely low levels of contamination with the possibility of automation. This will take us to a new level of automation, statistics and coverage of the parameter space.
The overarching goal of this project is to make use of and further develop our recently constructed microfluidics platform for quantifying atmospheric ice nucleating particle concentrations.
The overarching goal of this project is to make use of and further develop our recently constructed microfluidics platform for quantifying atmospheric ice nucleating particle concentrations. This will involve:
1. Learning to use our existing systems for quantifying ice nucleation in atmospheric samples.
2. Use our aerosol sampling equipment at the new Leeds Atmospheric Observatory to collect samples for analysis with the microfluidics system
3. Develop analytical tools to characterise the particles in frozen droplets, relative to unfrozen droplets, which will be separated with our new sorting device.
4. Develop a technique to sample aerosol into liquid water which is then fed directly into the microfluidic device. This would be a powerful micro total analysis system.
If you would like to learn more, contact Prof. Benjamin Murray ([email protected]
About the Centre for Doctoral training in Aerosol Science:
Aerosol science is crucial to disciplines as broad ranging as drug delivery to the lungs, transmission of disease, climate change, energy and combustion science, novel materials, and consumer and agricultural products.
An aerosol is any collection of particles dispersed in a gas. The CDT brings together a multi-disciplinary team of 80 post-graduate students and academics from 7 UK universities spanning the physical, environmental and health sciences, and engineering. Our aim is to tackle the global challenges in which aerosol science is key.
Further details are available from our website: https://www.aerosol-cdt.ac.uk/
Doctoral Training in Aerosol Science:
During your doctorate, you will learn to research in diverse multidisciplinary teams, gain an advanced understanding of the core physical science of aerosols, and collaborate with industrial and public sector partners, equipping you to undertake ground-breaking research in aerosol science.
During the first 7 months of your PhD, you will join the CDT cohort based at the University of Bristol. Core training in aerosol science, research methods, professionalism and translation will be delivered by Team Based Learning.
You will then undertake a short research project at your home or partner institution before starting your PhD research. You will gain experience outside academia in a placement with an industrial/public sector partner in Year 2 or 3.
How to Apply:
Candidates who aspire to work in a multidisciplinary field, and hold or will achieve a minimum of an upper second-class undergraduate degree in any of these areas are encouraged to apply: chemistry, physics, biological sciences, life and medical sciences, mathematics and computer science, chemical and mechanical engineering, pharmaceutical and environmental sciences.
Apply via our website: https://www.aerosol-cdt.ac.uk/
Apply by 3rd February 2020– Applicants with a suitable academic background will be invited to attend a recruitment and assessment day in Bristol on February 10th. Applications after this date will be subject to remaining availability of studentships.
Hope, C.: The $10 trillion value of better information about the transient climate response, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 373, 20140429, doi:10.1098/rsta.2014.0429, 2015.
Murray, B. J., O'Sullivan, D., Atkinson, J. D., and Webb, M. E.: Ice nucleation by particles immersed in supercooled cloud droplets, Chem. Soc. Rev., 41, 6519-6554, 10.1039/c2cs35200a, 2012.
Tan, I., Storelvmo, T., and Zelinka, M. D.: Observational constraints on mixed-phase clouds imply higher climate sensitivity, Science, 352, 224-227, 10.1126/science.aad5300, 2016.
Tarn, M. D., Sikora, S. N. F., Porter, G. C. E., O’Sullivan, D., Adams, M., Whale, T. F., Harrison, A. D., Vergara-Temprado, J., Wilson, T. W., Shim, J.-u., and Murray, B. J.: The study of atmospheric ice-nucleating particles via microfluidically generated droplets, Microfluid. Nanofluid., 22, 52, 10.1007/s10404-018-2069-x, 2018.