ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-11-2015-2011 VOCALS-CUpEx: the Chilean Upwelling Experiment Garreaud R. D. 1 Rutllant J. A. 1 2 Muñoz R. C. 1 Rahn D. A. 1 Ramos M. 2 3 Figueroa D. 4 Department of Geophysics, Universidad de Chile, Santiago, Chile Center for Advanced Studies in Arid Zones (CEAZA), La Serena, Chile Facultad de Ciencias del Mar, Universidad Católica del Norte, Coquimbo, Chile Department of Geophysics, Universidad de Concepción, Concepción – Chile 04 03 2011 11 5 2015 2029 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/11/2015/2011/acp-11-2015-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/2015/2011/acp-11-2015-2011.pdf

The VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) was a major field experiment conducted in spring of 2008 off southern Peru and northern Chile, aimed at better understanding the coupled climate systems of the southeast Pacific. Because of logistical constrains, the coastal area around 30° S was not sampled during VOCALS-REx. This area not only marks the poleward edge of the subtropical stratocumulus cloud regime (thus acting as a source of transient disturbances) but is also one of the most active upwelling centers and source of surface ocean kinetic energy along the Chilean coast. To fill such an observational gap, a small, brief, but highly focused field experiment was conducted in late spring 2009 in the near-shore region around 30° S. The Chilean Upwelling Experiment (CUpEx) was endorsed by VOCALS as a regional component. <br><br> CUpEx included long-term monitoring, an intensive two-week field campaign and off-shore research flights. Our goal was to obtain an atmospheric/oceanic dataset with enough temporal and spatial coverage to be able to document (a) the mean diurnal cycles of the lower-troposphere and upper-ocean in a region of complex topography and coastline geometry, and (b) the ocean-atmosphere response to the rapid changes in coastal winds from strong, upwelling-favorable equatorward flow (southerly winds) to downwelling-favorable poleward flow (northerly winds). In this paper we describe the measurement platforms and sampling strategy, and provide an observational overview, highlighting some key mean-state and transient features.

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