Our lack of knowledge of how clouds will respond to a changing climate represents one of the largest sources of uncertainty in our projections of future climate (Murray et al., 2020). 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. However, the sources, characteristics and distribution around the globe of INPs is extremely poorly understood. In part, this is due to our lack of instrumentation capable of making the necessary measurements of INPs and our ability to identify the aerosol particle types which nucleate ice.
A particularly poorly understood class of ice-nucleating particles are those derived from biological sources. Certain types of bacteria, fungus, pollen and sub-components of these materials are some of the most active ice-nucleating materials we know of. But their concentration, seasonal cycles and atmospheric distribution are largely unknown.
In Leeds, we have developed a microfluidic tool to address these problems: LOC-NIPI. This device cools 100 µm sized droplets in a flowing system and counts the fraction that freeze (Tarn et al. 2020) and then sorts frozen and unfrozen droplets (Porter et al., 2020).
Objectives:
The overarching goal of this project is to quantify and identify atmospheric biological ice-nucleating particles. This will involve:
- Learning to use our existing microfluidic systems (LOC-NIPI) for quantifying ice nucleation in atmospheric samples.
- Use an electrostatic precipitation system to collect atmospheric particles onto a glass slide and then collect these into a small volume of liquid for subsequent analysis using LOC-NIPI.
- Use a combination of our standard aerosol samplers and the University of Hertfordshire’s electrostatic precipitator to collect aerosol at the University of Leeds Research Farm and also the Rothamsted Research site, with our partner Jon West, to collect samples for analysis with the microfluidic system from fields containing defined crops and also from a wind tunnel in which we can place specific samples of interest.
- Culture biological ice-nucleating bacteria or fungus for subsequent identification and/or use PCR (polymerase chain reaction) techniques to amplify the DNA from single particles recovered from individual frozen droplets separated in our droplet sorting system.
- Work towards a micro total analysis system for ice-nucleating particles where aerosol are collected and then autonomously transferred to the microfluidic device.
If you would like to learn more, contact Prof. Benjamin Murray ([Email Address Removed])
About the Centre for Doctoral training in Aerosol Science (https://www.aerosol-cdt.ac.uk/)
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.
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.
Applications:
Apply by 9am on Monday 25th January 2021. Eligible applicants with a suitable academic background will be invited to attend an online recruitment and assessment day on 1st February 2021. Applications after this date will be subject to remaining availability of studentships.
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.
Continue with Facebook
