DCMEX -- Deep Convective Microphysics EXperiment

The goal of the DCMEX project is to ultimately reduce the uncertainty in equilibrium climate sensi-
tivity by improving the representation of microphysical processes in global models. It is the anvils
produced by tropical systems in particular that contribute significantly to cloud feedbacks. The anvil
radiative properties, lifetimes and areal extent are the key parameters. DCMEX will determine the
extent to which these are influenced, or even controlled by the cloud microphysics including the
habits, concentrations and sizes of the ice particles that make up the anvils, which in turn depend
on the microphysical processes in the mixed-phase region of the cloud as well as those occurring in
the anvil itself.

There has been a rapid advancement in the sophistication of global climate models in recent
years. Yet some of the equations used to represent microphysics processes are based on a poorer
physical understanding than desired. Gettelman and Sherwood (2016), for example pointed out
that there is significant spread in determining cloud feedbacks across different global models due
to uncertainties in microphysical processes, such as the treatment of ice processes. Ceppi et al.
(2017) also concluded that accurately representing clouds and their radiative effects in global models
remains challenging partly due to the difficulty in representing the cloud microphysics, as well as the
interactions between microphysics and dynamics. The microphysical and radiative processes and dynamics that control the opacity and areal coverage of tropical anvil clouds are not well represented in global climate models.

DCMEX will make novel measurements of cloud microphysics in a real-world laboratory convective cloud system - both the mixed-phase region and anvil - as well as improve and test models
and then apply them globally to tropical deep convective systems. We propose to deploy the FAAM
aircraft along with two dual-polarisation, Doppler radars and airborne and ground-based...