In 2007, the ARM Mobile Facility participated in one of the most ambitious field studies ever conducted in Europe—the Convective and Orographically Induced Precipitation Study (COPS). Now, 21 papers published in a special issue of the Quarterly Journal of the Royal Meteorological Society demonstrate that the data collected during COPS are providing new insight into:

• the key chemical and physical processes leading to convection initiation and to the modification of precipitation by orography;
• the improvement of quantitative precipitation forecasting by the assimilation of new observations; and
• the performance of ensembles of convection-permitting models in complex terrain.

Between June and August 2007, COPS took place in the low-mountain area of southwestern Germany and eastern France. Researchers obtained data using in situ sensors on 10 aircraft and remote sensing instruments in a 10,000-station network of new and existing ground measurement and GPS sites covering the Vosges Mountains, the Rhine Valley, and the Black Forest Mountains.

As one of five supersites established for the campaign, the ARM Mobile Facility operated for nine months near the village of Heselbach in the Murg Valley of the Black Forest. It is described in the issue’s editorial as a “unique backbone” for the COPS measurements. Subscribers to the QJRMS can view all papers in the special issue, Volume 137, Issue S1, published January 2011.