Infra-red effects of atmospheric cluster-ions
Cluster-ions, tiny electrically charged particles, are continuously generated in the atmosphere by natural radioactivity (from rocks beneath porous surface materials), and cosmic rays (from space). The nanometre-sized cluster-ions consist of a few molecules hydrogen-bonded to a charged central atom. Bending and stretching of the hydrogen bonds means that these cluster-ions absorb infra-red radiation. Infra-red effects of atmospheric cluster-ions have already been observed both in the laboratory and in an atmospheric experiment. The infra-red absorption of cluster ions could potentially have both global and continuous effects on weather and climate, motivating the need to better quantify the effects for inclusion in meteorological and radiative transfer models. This project will involve investigation of the atmospheric effects of the cluster ions.
This will be an experimental project, with the techniques developed first in a laboratory, before atmospheric measurements take place. The methodology will involve artificially enhancing the natural background cluster-ion concentration with, for example, a corona ion source, and measuring both the ionisation and the infra-red absorption. Electric fields can be applied to remove the cluster-ions, to evaluate the change in infra-red absorption between their presence and absence. Natural fluctuations in atmospheric ionisation due to space weather events and radioactivity will also be exploited. The aim of the project is to determine how the infra-red absorption varies with cluster-ion concentration across a range of atmospheric conditions, a currently neglected effect in atmospheric and climate models.
- Featured Supervisors and available topics
- Improving fire emission estimates
- Stability and resilience of tropical vegetation transitions
- The role of pollinators in plant species diversification in the Greater Cape Floristic Region, South Africa
- Improving yield and nutritional quality of legumes through managing soil biodiversity and pollination services – sustainable and nutritious legumes in India
- Does increased diversity cause increased predation pressure?
- Are niches smaller when there are more species? A quantitative investigation of niche partitioning over the Phanerozoic
- Disentangling the dynamics of diversification in deep time
- Infra-red effects of atmospheric cluster-ions
- Toward a mechanistic understanding of glacial-interglacial cycles in atmospheric CO2
- Plankton Speciation and Adaptation in the Open Ocean
- Quantifying ocean heat and anthropogenic carbon uptake
- Constraining the Cycle of Natural and Anthropogenic Lead in the Ocean
- Observing the Origins of Tropical Cyclones
- Deciphering the role of drought and fire in tropical ecosystems