The moisture cycle in cyclones

Mid-latitude weather systems play a key role in cycling moisture in the atmosphere: they transport moisture from the sub-tropics (where it is evaporated from over the warm ocean surface) towards the poles. They also act to transport near-surface moisture to higher altitudes. Much, but not all, of the cycled moisture is rained out of the atmosphere by these weather systems. In some recent research we have used a series of idealised numerical simulations to unravel how this cycling works.

We now intend to examine how moisture cycling by mid-latitude weather system works in real-world systems, primarily by analysing simulations of fully realistic systems from high-resolution numerical models. We believe that our previous idealised studies are very valuable in providing a robust qualitative description of the moisture transports and their main sensitivities, but real-world processes omitted in idealized simulations may have important roles to play.

Some links for this work:

Publications:

1. PhD thesis by David McNamara on boundary layer ventilation
2. A paper on moisture transport by mid-latitude cyclones
3. PhD thesis by Ian Boutle on boundary-layer processes in mid-latitude cyclones
4. A paper on the boundary-layer structure in moist baroclinic waves

Talks:

1. A talk, with accompanying audio recording, presented by Stephen Belcher at the AMS 19th Symposium on Boundary Layers and Turbulence, Keystone in August 2010.
2. A seminar, and accompanying animation, presented at the University of East Anglia.
3. A talk presented by Ian Boutle as a departmental seminar. (Also as a seminar at the University of Exeter.)
4. A talk presented by Stephen Belcher on boundary layer ventilation at a symposium on air pollution.
5. A talk presented by Ian Boutle on moisture transport in baroclinic waves, at the 2009 EGU conference in Vienna. (Also available as a powerpoint, with animations included.)

Posters:

1. A case study of moisture ventilation, presented by David McNamara at a Met Office poster conference in February 2012.
2. A poster on moisture transport in baroclinic waves, presented by Ian Boutle at the Royal Met Soc 2009 Conference in June 2009.