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Photo of Dr Ruth Geen

Dr Ruth Geen

Research Fellow


Telephone: 01392 723612

Extension: (Streatham) 3612

I’m a Research Fellow in the Exeter Climate Systems group. I am working with Hugo Lambert and Geoff Vallis on the Climate Science for Service Partnership: China project, which aims to improve climate services over China. Having arrived in Exeter in January 2016, I am currently researching the large-scale dynamics involved in the East Asian monsoon. By running simulations where land-surface characteristics and topography are varied, I hope to improve understanding of the key controls on the monsoon, and how this high impact system may change in the future.


Other work and interests

  • Latent heat feedbacks onto climate 

Before coming to Exeter, I studied for my PhD in the Space and Atmospheric Physics group at Imperial College London, supervised by Arnaud Czaja and Joanna Haigh. My work there investigated the effects of latent heat release by water vapour on the climate system in aquaplanet models, in particular the effects on heat transport by midlatitude storms. My PhD thesis can be found here. 

  • Simple radiation scheme

As part of my PhD work, I developed a simple three band radiation scheme for the MITgcm. This accounts for water vapour and carbon dioxide, and separates the spectrum into shortwave, longwave window, and longwave non-window components, providing a more realistic alternative to using fixed optical depths, while still being fast to run. During a visit to MIT, working with John Marshall, in November 2015 I helped to incorporate this into the model source code repository, and it is available here.



Ruth Geen, 2020: Forecasting South China Sea Monsoon Onset Using Insight from Theory. Submitted to Geophysical Research Letters.

Ruth Geen, F. H. Lambert and G. K. Vallis, 2020: The Asian Monsoons as a Unified System. Submitted to Geophysical Research Letters.

Ruth Geen, S. Bordoni, D. S. Battisti and K. L. Hui, 2020: Monsoons, ITCZs and the Concept of the Global Monsoon. Reviews of Geophysics (in press).

Ruth Geen, F. H. Lambert and G. K. Vallis, 2019: Processes and Timescales in Onset and Withdrawal of 'Aquaplanet Monsoons'J. Atmos. Sci., 76:2357-2373

Ruth Geen, F. H. Lambert and G. K. Vallis, 2018: Regime change behaviour during Asian monsoon onset. J. Clim., 31:3327-3348

Geoffrey K. Vallis, Greg Colyer, Ruth Geen, Ed Gerber, Martin Jucker, Penelope Maher, Alex Paterson, Marianne Pietschnig, James Penn, and Stephen Thomson, 2018: Isca, v.1.0: a framework for the global modelling of the atmospheres of Earth and other planets at varying levels of complexity. Geosci. Model Dev., 11:843-859

Gabriele Messori, Ruth Geen and Arnaud Czaja, 2017: On the spatial and temporal variability of atmospheric heat transport in a hierarchy of models. J. Atmos. Sci., 74:2163-2189

Ruth Geen, Arnaud Czaja and Joanna D. Haigh, 2016: The effects of increasing humidity on heat transport by extratropical waves. Geophysical Research Letters, 43:8314-8321