2nd Workshop on Cloud Organization (WCO2)

Session

Deep convection and more

18 May 2022, 11:00

Public Library (Utrecht)

25. Evaluation of ECMWF lightning forecast over Indian subcontinent during 2020 premonsoon months

Dr Parthasarathi Mukhopadhyay (Indian Institute of Tropical Meteorology)

18/05/2022, 11:00

Talk

Convective cumulus clouds with vigorous updrafts and downdrafts form thunderstorms. Severe thunderstorms consist of multiple thunderclouds at different stages, and the storm itself has a longer lifetime than individual cells. As the convective clouds grow larger, the negative charge accumulates in their lower region, and the positive charge in the upper level forms a dipole. When the charge...

49. A cold pool perturbation scheme to improve convective initiation in convection-permitting models

Mirjam Hirt

18/05/2022, 11:15

Talk

Cold pools are essential for organizing and initiating convection. In a recent investigation, we identified several sensitivities of cold pool driven convective initiation to model resolution within hectometer simulations. In particular, a causal graph analysis has revealed that the dominant impact of model resolution on convective initiation is a direct consequence of weak...

39. Dependency of precipitation and cloud radiative feedback on subgrid scale clouds structure; a machine learning approach

Sara Shamekh (Columbia University)

18/05/2022, 11:30

Talk

The organization of convective clouds has been argued to have a significant impact on the atmospheric humidity and circulation, as well as precipitation and cloud radiative feedback, yet global models do not include a parameterization of unresolved subgrid cloud structure. In this study, we investigate the necessity of including subgrid scale cloud structure in the model and whether it...

48. Reassessing the Cohen and Craig (2006) theory: Fluctuations in an equilibrium convective cloud ensemble at horizontal resolutions ranging from 2 km to 125 m

Dr Julien Savre (Ludwig-Maximilians-Universität Munich)

18/05/2022, 11:45

Talk

About 15 years ago, Cohen and Craig (2006, CC06) proposed a general theory describing the fluctuations of the properties characterising a convective cloud ensemble developing under fixed external forcing. This theory later served as the basis of the Plant-Craig stochastic convection scheme which has been in particular implemented in the ICON model operated by the German weather service....

30. Moisture transports and rain cell statistics in organised convection and their potential role in super Clausius-Clapeyron scaling

Geert Lenderink (KNMI)

18/05/2022, 12:00

Talk

In observations of (sub)hourly precipitation, it is often found that the extremes display a dependency on (dew point) temperature exceeding the Clausius-Clapeyron (CC) relation. Such super CC behaviour is commonly explained by dynamical feedback mechanisms in convective clouds whereby enhanced latent heating (and cooling due to evaporation) could produce more vigorous, or more organised...

15. Parametrising cold-pool effects in the Met Office Unified Model

Gabriel Rooney (Met Office UK)

18/05/2022, 12:15

Talk

Cold pools formed by convective downdraughts can feed back onto the organisation and diurnal cycle of convection. This presentation describes a parametrisation of cold pools, C-POOL, recently developed within the Met Office Unified Model (UM). The parametrisation includes forcing by downdraughts, dissipation, and various pathways for influencing parametrised convection in the UM. It also...