The physical processes inside clouds are one of the most unknown components of weather and climate systems. A description of cloud processes through the use of standard meteorological parameters in numerical models has to be strongly improved to accurately describe the characteristics of hydrometeors, latent heating profiles, radiative balance, air entrainment and cloud updrafts and downdrafts. Numerical models have been improved to run at higher spatial resolutions where it is necessary to describe explicit these cloud processes. For instance, to analyze the effects of global warming in a given region it is necessary to perform simulations taking into account all of these cloud processes described above. Another important application which requires this knowledge is satellite precipitation estimation.
The Brazilian space program is planning to launch, in 2014 a satellite to measure precipitation, which will be part of the GPM (Global Precipitation Measurement) constellation program. Warm clouds are responsible for a large amount of the precipitation in the tropics, especially in coastal regions. This cloud type is little studied and is not considered in satellite rainfall retrievals. This project will carry out field experiments at seven sites to investigate the different precipitation regimes in Brazil. To study these precipitation regimes, the field campaigns will make use of dual polarization radar, lidar, microwave radiometers, disdrometer, radiosonde and various other instruments.
The analysis will be performed focusing on the microphysical evolution and cloud life cycle, different precipitation estimation algorithms, the development of thunderstorms and lightning formation, processes in the boundary layer and cloud microphysical modeling. This project intends to extend the knowledge of these cloud processes to reduce the uncertainties in precipitation estimation, mainly from warm clouds and, consequently, improving the knowledge of the water and energy budget and cloud microphysics. This research project will carry out studies on climate and physical processes by way of conventional and special observations in order to create a database that can describe the cloud processes of the main precipitating system in Brazil. Accordingly, this proposal aims at the development of a database that can be carried out to improve remote sensed precipitation estimation, thus validating and improving cloud microphysical parameterization in cloud models. This project will especially focus on the warm cloud precipitation produced by different types of convection.