Graham Lee

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Graham Lee

Postdoctoral Researcher - Bernoulli Fellow

For an updated list of published papers search: orcid:0000-0002-3052-7116 in NASA/ADS.

I am a postdoctoral researcher working in the exoplanet planetary dynamics and climate group at AOPP. I also have significant links to the Center for Space and Habitability (CSH) group in Bern, Switzerland through the Bernoulli fellowship:
http://www.csh.unibe.ch/index_eng.html

I research the formation of cloud structures in exoplanet and Brown Dwarf atmospheres, in particular:
- What are the chemical mechanisms for cloud formation in exoplanet atmospheres?
- What are the microphysical processes responsible for shaping the local and global distribution of global cloud structures?
- What are the key cloud condensation nuclei (CCN) species for exoplanet cloud formation?
- How does radiation propagate in cloudy atmospheres, and what are the 3D effects on the observable properties of exoplanets due to cloud?

I make use of Global Circulation Models (GCMs) of exoplanet atmospheres, coupled with cloud formation models to explore the global cloud structures these worlds may exhibit.
To explore cloudy questions, I maintain a time dependent microphysical cloud formation code, DIHRT, suitable for GCM (and other hydrodynamic) models of hot Jupiters and Brown dwarfs.

I have also developed a 1D spectral/bin microphysical model, DMC, which attempts to resolve the size distribution of the cloud particles.
With a few modifications, DMC can also be made 3D able.

I am also interested in the 3D radiative-transfer effects of cloud particles and the 3D radiative environment of exoplanet atmospheres. I am maintaining a 3D Monte Carlo radiative-transfer code, Cloudy Monte Carlo Radiative Transfer (CMCRT), which aims to model photon processes with high accuracy, from post-processing transmission/emission spectra to photo-chemical haze and photo-ionisation modelling. The attached gif shows an RGB approximation of one of my cloudy GCM models, processed using the Mote Carlo code.

If you are interested in using any of my codes, please contact me, i'm happy to collaborate on your cloudy problems!
They will be made public at some point, but are a bit tricky to use out of the box currently!