ACP Atmospheric Chemistry and Physics ACP Atmos. Chem. Phys. 1680-7324 Copernicus Publications Göttingen, Germany 10.5194/acp-11-627-2011 The VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx): goals, platforms, and field operations Wood R. 1 Mechoso C. R. 2 Bretherton C. S. 1 Weller R. A. 3 Huebert B. 4 Straneo F. 3 Albrecht B. A. 5 Coe H. 6 Allen G. 6 Vaughan G. 6 Daum P. 7 Fairall C. 8 Chand D. 1 24 Gallardo Klenner L. 9 Garreaud R. 9 Grados C. 10 Covert D. S. 1 Bates T. S. 11 Krejci R. 12 Russell L. M. 13 de Szoeke S. 14 Brewer A. 8 Yuter S. E. 15 Springston S. R. 7 Chaigneau A. 17 Toniazzo T. 16 Minnis P. 18 Palikonda R. 23 Abel S. J. 19 Brown W. O. J. 20 Williams S. 20 Fochesatto J. 21 Brioude J. 8 22 Bower K. N. 6 Department of Atmospheric Sciences, University of Washington, Seattle, USA UCLA, Los Angeles, USA Woods Hole Oceanographic Institution, USA University of Hawai'i, Honolulu, USA Rosenstiel School of Marine and Atmospheric Science, University of Miami, USA School of Earth, Atmospheric and Environmental Sciences, University of Manchester, UK Brookhaven National Laboratory, Upton, USA NOAA Earth System Research Laboratory, Boulder, USA Departamento de Geofisica, Universidad de Chile, Chile Instituto del Mar del Perú, Perú NOAA Pacific Marine Environmental Laboratory, Seattle, USA Dept. of Applied Environmental Science (ITM), Stockholm University, Sweden Scripps Institution of Oceanography, University of California, San Diego, USA Oregon State University, Corvallis, USA North Carolina State University, Raleigh, USA Department of Meteorology, University of Reading, UK L'Institut de Recherche pour le Développement, Marseille, France NASA Langley Research Center, Hampton, USA The Met Office, Exeter, UK National Center for Atmospheric Research, Boulder, USA University of Alaska, Fairbanks, USA Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA Science Systems and Applications, Inc., Hampton, USA currently at: Pacific Northwest National Laboratory, Richland, USA 21 01 2011 11 2 627 654 Copyright: © 2011 R. Wood et al. 2011 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://acp.copernicus.org/articles/11/627/2011/acp-11-627-2011.html The full text article is available as a PDF file from https://acp.copernicus.org/articles/11/627/2011/acp-11-627-2011.pdf

The VAMOS<sup>1</sup> Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) was an international field program designed to make observations of poorly understood but critical components of the coupled climate system of the southeast Pacific. This region is characterized by strong coastal upwelling, the coolest SSTs in the tropical belt, and is home to the largest subtropical stratocumulus deck on Earth. The field intensive phase of VOCALS-REx took place during October and November 2008 and constitutes a critical part of a broader CLIVAR program (VOCALS) designed to develop and promote scientific activities leading to improved understanding, model simulations, and predictions of the southeastern Pacific (SEP) coupled ocean-atmosphere-land system, on diurnal to interannual timescales. The other major components of VOCALS are a modeling program with a model hierarchy ranging from the local to global scales, and a suite of extended observations from regular research cruises, instrumented moorings, and satellites. The two central themes of VOCALS-REx focus upon (a) links between aerosols, clouds and precipitation and their impacts on marine stratocumulus radiative properties, and (b) physical and chemical couplings between the upper ocean and the lower atmosphere, including the role that mesoscale ocean eddies play. A set of hypotheses designed to be tested with the combined field, monitoring and modeling work in VOCALS is presented here. A further goal of VOCALS-REx is to provide datasets for the evaluation and improvement of large-scale numerical models. VOCALS-REx involved five research aircraft, two ships and two surface sites in northern Chile. We describe the instrument payloads and key mission strategies for these platforms and give a summary of the missions conducted. <br><br> <sup>1</sup> Variability of the American Monsoon Systems, an international CLIVAR program.

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