Atmospheric Radiation Measurement Climate Research Facility US Department of Energy

Convective and Orographically-induced Precipitation Study (COPS)

2 April 2007 - 31 December 2007

Lead Scientist: Volker Wulfmeyer

Observatory: amf, fkb

The ARM Mobile Facility (AMF) was deployed and operated in the Black Forest area during the Convective and Orographically-induced Precipitation Study (COPS) in summer 2007. The COPS region can be characterized by significant orographic precipitation with most of the summertime precipitation being convective. Due to major problems in predicting this type of precipitation, the area was chosen as a natural laboratory for convection during the intensive observational period of the German priority program on Quantitative Precipitation Forecasting (PWP) funded for a six-year period by the German Research Foundation (DFG). The aim was to identify the reasons of deficiencies in QPF and to improve the skill of mesoscale model forecasts with respect to precipitation. During the COPS field campaign, large efforts were put on observing the four-dimensional state of the atmosphere from the pre-convective environment, to the initiation of convection to the formation of clouds, to the development and decay of precipitation. For this purpose, measurements from several super sites (similar to the AMF) within an area of about 100 x 100 km2 were combined with satellite and radar data. At the super sites, a number of new scanning remote sensing instruments (cloud radar, lidar, microwave radiometer) were deployed. To transfer the COPS results to a larger scale, a General Observations Period (GOP) of the PQP covered the area of central Europe and the full year 2007. Here, close cooperation with the CloudNET project (stations Cabauw, Chilbolton, and Lindenberg) took place to derive a set of cloud microphysical parameters using novel synergetic algorithms and to compare those with numerical modeling results. For an improved connection between COPS and the GOP, researchers performed continuous measurements of the AMF for nine months at a special observation site in the COPS area where initiation of convection and cloud formation can often be expected. As COPS and the GOP have an open data policy, these data are available for all collaborators. The following science questions were investigated by combining the AMF, COPS, GOP and CloudNET data:

  • What are the processes responsible for the formation and evolution of convective clouds in orographic terrain?
  • What are the microphysical properties of orographically induced clouds and how do these depend on dynamics, thermodynamics, and aerosol microphysics?
  • How can convective clouds in orographic terrain be represented in atmospheric models based on AMF, COPS, and GOP data?

To answer these science questions, the observations (ground-based, air- and satellite-borne) were strongly linked with atmospheric models ranging from detailed cloud microphysical models over state-of-the-art mesoscale models used in short-range weather prediction to general circulation models. Using this set of tools, researchers investigated how representative the observations were of an atmospheric column by the AMF and the other CloudNET stations for a model grid box (from about 2 to 200 km) in orographic terrain. The PQP program was coordinated with other international research programs such as the MAP Forest Demonstration Project (FDP) and THORPEX of the World Weather Research Program (WWRP). A strong collaboration between modelers, instrument principal investigators, weather services within international research programs and organizations were established. Consequently, the PQP community provided and studied unique data sets of observations and model results for addressing the science questions above.

The AMF helped scientists collect data about orographic precipitation, which is common in the Black Forest, particularly in the summertime.

The AMF helped scientists collect data about orographic precipitation, which is common in the Black Forest, particularly in the summertime.


  • Child Campaign


Zhang C and J Moore. 2023. "A Road Map to Success of International Field Campaigns in Atmospheric and Oceanic Sciences." Bulletin of the American Meteorological Society, 104(1), 10.1175/BAMS-D-22-0133.1.


Titos G, M Burgos, P Zieger, L Alados-Arboledas, U Baltensperger, A Jefferson, J Sherman, E Weingartner, B Henzing, K Luoma, C O'Dowd, A Wiedensohler, and E Andrews. 2021. "A global study of hygroscopicity-driven light-scattering enhancement in the context of other in situ aerosol optical properties." Atmospheric Chemistry and Physics, 21(17), 10.5194/acp-21-13031-2021.


Burgos M, E Andrews, G Titos, A Benedetti, H Bian, V Buchard, G Curci, Z Kipling, A Kirkevåg, H Kokkola, A Laakso, J Letertre-Danczak, M Lund, H Matsui, G Myhre, C Randles, M Schulz, T van Noije, K Zhang, L Alados-Arboledas, U Baltensperger, A Jefferson, J Sherman, J Sun, E Weingartner, and P Zieger. 2020. "A global model–measurement evaluation of particle light scattering coefficients at elevated relative humidity." Atmospheric Chemistry and Physics, 20(17), 10.5194/acp-20-10231-2020.

Muradyan P and R Coulter. 2020. Radar Wind Profiler (RWP) and Radio Acoustic Sounding System (RASS) Instrument Handbook. Ed. by Robert Stafford, U.S. Department of Energy. DOE/SC-ARM/TR-044. 10.2172/1020560.


Burgos M, E Andrews, G Titos, L Alados-Arboledas, U Baltensperger, D Day, A Jefferson, N Kalivitis, N Mihalopoulos, J Sherman, J Sun, E Weingartner, and P Zieger. 2019. "A global view on the effect of water uptake on aerosol particle light scattering." Scientific Data, 6(1), 10.1038/s41597-019-0158-7.

Tang S, S Xie, Y Zhang, and DR Cook. 2019. The QCECOR Value-Added Product: Quality-Controlled Eddy Correlation Flux Measurements. Ed. by Robert Stafford, ARM user facility. DOE/SC-ARM-TR-223. 10.2172/1557426.

Wood R, G Zhang, N Hickmon, M Jensen, S Klein, R Leung, D Mechem, and P Zuidema. 2019. Atmospheric Radiation Measurement (ARM) User Facility ARM Mobile Facility Workshop Report. Ed. by Rolanda Jundt, Robert Stafford, U.S. Department of Energy Office of Science. DOE/SC-0197. 10.2172/1510259.

Lammert A, A Hansen, F Ament, S Crewell, G Dick, V Grützun, H Klein-Baltink, V Lehmann, A Macke, B Pospichal, W Schubotz, P Seifert, E Stamnas, and B Stevens. 2019. "A Standardized Atmospheric Measurement Data (SAMD) Archive for distributed cloud and precipitation process-oriented observations in Central Europe." Bulletin of the American Meteorological Society, 100(7), 10.1175/BAMS-D-18-0174.1.


Miller MA, K Nitschke, TP Ackerman, WR Ferrell, N Hickmon, and M Ivey. 2016. The ARM Mobile Facilities. In Meteorological Monographs vol.57, pp. 1-15. Washington, D.C.: American Meteorological Society.

Berg L and P Lamb. 2016. "Surface Properties and Interactions: Coupling the Land and Atmosphere within the ARM Program." Meteorological Monographs, 57, 10.1175/AMSMONOGRAPHS-D-15-0044.1.

View All Related Publications

FKB Data Sources

Name Full Name Browse Data
AERI Atmospheric Emitted Radiance Interferometer Browse Data
AERINF AERI Noise Filtered Browse Data
AIP Aerosol Intensive Properties Browse Data
AOD-MFRSR Aerosol Optical Depth (AOD) derived from MFRSR measurements Browse Data
AOS Aerosol Observing System Browse Data
CAMSITE camera that monitors a site area Browse Data
CCN Cloud Condensation Nuclei Particle Counter Browse Data
CEIL Ceilometer Browse Data
CSPHOT Sunphotometer Browse Data
ECMWFDIAG European Centre for Medium Range Weather Forecasts Diagnostic Analyses Browse Data
ECOR Eddy Correlation Flux Measurement System Browse Data
GNDRAD Ground Radiometers on Stand for Upwelling Radiation Browse Data
MERGESONDE Merged Sounding Browse Data
MET Surface Meteorological Instrumentation Browse Data
MFRSR Multifilter Rotating Shadowband Radiometer Browse Data
MFRSRCLDOD Cloud Optical Properties from MFRSR Using Min Algorithm Browse Data
MPL Micropulse Lidar Browse Data
MPLAVG MPL: data averaged to fixed 30 second interval, e.g. for polarized data Browse Data
MPLCMASK Cloud mask from Micropulse Lidar Browse Data
MWR Microwave Radiometer Browse Data
MWRHF Microwave Radiometer - High Frequency Browse Data
MWRP Microwave Radiometer Profiler Browse Data
MWRRET MWR Retrievals Browse Data
NCEPGFS National Centers for Environment Prediction Global Forecast System Browse Data
NFOV Narrow Field of View Zenith Radiometer Browse Data
PBLHT Planetary Boundary Layer Height Browse Data
QCECOR Quality Controlled Eddy Correlation Flux Measurement Browse Data
QCRAD Data Quality Assessment for ARM Radiation Data Browse Data
RADFLUXANAL Radiative Flux Analysis Browse Data
RWP Radar Wind Profiler Browse Data
SKYRAD Sky Radiometers on Stand for Downwelling Radiation Browse Data
SONDE Balloon-Borne Sounding System Browse Data
SONDEADJUST Sonde Adjust Browse Data
TSI Total Sky Imager Browse Data
VISST Minnis Cloud Products Using Visst Algorithm Browse Data
WACR W-Band (95 GHz) ARM Cloud Radar Browse Data
WACRARSCL W-band Cloud Radar Active Remote Sensing of Cloud Browse Data