Special Issue Features 22 Articles on Large European Field Experiment


This month’s Quarterly Journal of the Royal Meteorological Society Special Issue gives an overview of the scientific results of the Convective and Orographically-induced Precipitation Study (COPS). The ARM Mobile Facility participated in the large, international COPS experiment that was conducted from June to August 2007 in a low-mountain area in southwestern Germany and eastern France covering the Vosges Mountains, the Rhine Valley and the Black Forest Mountains. An unprecedented combination of in situ instruments and remote-sensing systems constituted the largest combination of multi-wavelength passive and active remote-sensing systems deployed during a field campaign to date. The objective of COPS was to improve the skill of quantitative precipitation forecasting (QPF) in the models, one of the major challenges of atmospheric science. The focus of COPS was on analyses and model representations of the physical and chemical processes responsible for the deficiencies in QPF over low-mountain regions. Some of the most severe deficiencies in QPF have been identified in regions of orographic terrain, which are prone to flash-flood events, a major driver of COPS. One of the ARM-specific pagers examined the daytime cloud radiative effect (CRE) (i.e., the difference of cloudy and clear-sky net fluxes) for the period of the mobile facility deployment. The analysis shows that CRD uncertainty for overcast, single-layer water clouds is determined by uncertainties in liquid water content and effective radius.


Wulfmeyer, V., C. Flamant, A. Behrendt, A. Blyth, A. Brown, M. Dorninger, A. Illingworth, P. Mascart, A. Montani, and T. Weckwerth. 2011. “Advances in the Understanding of Convective Processes and Precipitation over Low-Mountain Regions Through the Convective and Orographically-Induced Precipitation Study (COPS),” Quarterly Journal of the Royal Meteorological Society, available online February 23, 2011, DOI: 10.1002/qj.799.