The overarching goal of the Colorado State University Convective CLoud Outflows and UpDrafts Experiment (C3LOUD-Ex) was to enhance our understanding of deep convective storm processes and how they are represented in numerical models. Pivotal to the experiment was a novel “Flying Curtain” strategy.
This project will explore the characteristics of the linear systems -- size, orientation, propagation - that lead to the most extreme rainfall events.
The accumulation of rainfall over a given area depends on a range of things, including duration, intensity, and propagation speed. It is the characteristics of convection that ultimately determine these rainfall properties. The idea for this project is to use a simple method to characterise the properties of the most intense convective / rainfall bearing systems from radar data.
A new paper by Martin Jucker and colleagues reveals the choice of a particular convection-resolving model (CRM) has a much larger impact on the results than increasing resolution. It also suggests the behaviour of CRMs is tied to model internals instead of the phenomena they are trying to reproduce.
To better assess the degree of organisation in radar observations CLEX researchers developed the Radar Organisation Metric (ROME). ROME's statistical properties suggest it is able to distinguish between the degree of convective organisation, and it also captures different regimes of the monsoon in Northern Australia.
This study found in CMIP5 models that are able to simulate both types of events, that convective extremes do not always coincide with warm extremes. The disassociation becomes more distinct under greenhouse warming with higher occurrences of convective extremes than warm extremes.
This paper investigates the annual cycle in cloud and rainfall measurements over the western equatorial Indian Ocean. While there is a single period of strong rainfall over the region during December-January each year, there are two periods of increased high-top clouds associated with convection.
This project analyzes satellite images and other observational data to study two-way interactions between convection and tropospheric waves. In particular, it investigates how these interactions influence patterns of convection and clouds. Numerical experiments in the form of high-resolution simulations are designed to support the results.
John Allen (Central Michigan University). Global Perspectives on Severe Convective Storms
This observational study of radiative convective equilibrium finds that this equilibrium breaks down in areas of a few thousands kilometres on a side. This has implications cloud model simulations in climate models.