GEWEX Process Evaluation Studies (GEWEX PROES) intend to provide observational based metrics for a better understanding of climate related physical processes and thus to advance their representation in research, weather and climate models.
Progress toward realistically simulating the energy and water cycle in weather and climate models has been slower than desirable. There are many reasons for this: Climate models participating in the CMIP5 project, while more comprehensive than their predecessors, have shown little to no improvement in simulating key features of the climate system. As a result, uncertainties in global climate sensitivity and in the simulation of the regional climates have not been reduced significantly. The community keenly awaits studies that underscore advances in CMIP6 over CMIP5.
This slow and in many ways unconvincing progress is in stark contrast to the significant advances that have occurred over the last decade or more in observing the energy and water cycles of the planet. The Obs4MIPs project (https://esgf-node.llnl.gov/projects/obs4mips/) attempted to bring the model and observational efforts together in order to exploit the observations in a more coherent way for model parameterization development and evaluation. At the Obs4MIPs –CMIP6 Planning meeting (April 2014), however, it was concluded that it is time to go beyond such an approach and take greater advantage of the opportunities that combinations of many of the existing data sets provide to i) better understand the mechanisms involved in energy and water exchanges on Earth; ii) diagnose the sources of major model shortcomings; and iii) implement the knowledge gained in new treatments of energy and water exchange processes in models.
GEWEX, through is decades of experience in producing global data sets, diagnosing model performance and executing comprehensive process studies has taken this challenge on. A new GEWEX-wide activity, the GEWEX Process Evaluation Studies (PROES), was created with the goal to advance process understanding and process representation in models through new efforts and in collaboration with already existing key groups. This initiative also builds a bridge between the GEWEX panels GDAP and GASS.
Three efforts have evolved while other efforts are developing:
PROES on Upper Tropospheric Clouds and Convection (UTCC PROES)
GEWEX Aerosol Precipitation process study
