Mesoscale organisation of tropical convection

Introduction

Recent research has shown that the spatial organisation of convection (and hence clouds) at the mesoscale (20-200 km) dramatically affects the Earth's energy balance and hydrological cycle. This raises the question as to how the organisation of convection will change with warming, and how it will influence the climate.

Challenges in Understanding Convection

A poor understanding of the physical drivers of the mesoscale organisation of convection, compounded by an inability to simulate and observe such processes, has hampered our ability to articulate this challenging question, let alone answer it.

Objectives of MAESTRO

In MAESTRO, I propose to develop observational approaches and analysis frameworks specifically designed to test mechanisms hypothesized to control the mesoscale organisation of both shallow and deep convective clouds.

Methodology

Advances in airborne remote sensing will be exploited to:

• Map the spatial structures of clouds and water vapor.
• Interpret their coupling through the analysis of coherent structures within the clear-air environment around clouds.
• Understand their dependence on environmental conditions.

Expected Outcomes

This will help to understand:

• Why and how convective clouds organise at the mesoscale.
• Why the organisation co-varies with water vapor, clouds, and radiation locally and remotely.
• Why it co-varies with climate conditions.

Integration of Observations

By connecting observations from the airborne measurements to satellite observations and meteorological analyses, the generality of the insights from the field measurements will be tested and tempered.

Assessment of Climate Models

Finally, observational insights will be used to assess the new and emerging generation of climate models whose resolution is fine enough to represent the mesoscale organisation of convection and its interaction with climate.

Conclusion

MAESTRO will lead to:

• New experimental techniques for studying atmospheric processes.
• An improved conceptualization of the interplay between convective organisation and climate.
• A critical assessment of the new generation of climate models for climate change studies.