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  • Author or Editor: K. Laursen x
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The development of the High-Performance Instrumented Airborne Platform for Environmental Research (HIAPER) will make possible a wealth of new geophysical research opportunities in the areas of atmospheric chemistry, climate forcing, weather system structure and evolution, the carbon and water vapor cycles, and ecosystem processes. In this paper, we present a brief background on the history of the HIAPER project and discuss the modifications made to the basic aircraft [a Gulfstream V (GV) business jet] and the infrastructure systems installed to transform it into an environmental research platform. General aircraft performance capabilities that make the GV uniquely suited for high-altitude, long-range studies of geophysical phenomena are also discussed. The conduct of research with HIAPER will require that suitable instrumentation payloads are available for use on the aircraft, and the processes followed by the National Science Foundation (NSF) and the National Center for Atmospheric Research (NCAR) for the development of an initial platform instrumentation suite to meet critical measurements needs are described. HIAPERs unique configuration and capabilities will make it an effective tool for the conduct of weather and water cycle research, the study of atmospheric chemistry and climate forcing, and the monitoring of biosphere structure and productivity, as we shall discuss. We conclude with an overview of the objectives of the initial HIAPER flight-testing program and the process whereby this new research platform will be made available to members of the scientific community for the support of environmental research.

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Bjorn Stevens, Donald H. Lenschow, Gabor Vali, Hermann Gerber, A. Bandy, B. Blomquist, J. -L. Brenguier, C. S. Bretherton, F. Burnet, T. Campos, S. Chai, I. Faloona, D. Friesen, S. Haimov, K. Laursen, D. K. Lilly, S. M. Loehrer, Szymon P. Malinowski, B. Morley, M. D. Petters, D. C. Rogers, L. Russell, V. Savic-Jovcic, J. R. Snider, D. Straub, Marcin J. Szumowski, H. Takagi, D. C. Thornton, M. Tschudi, C. Twohy, M. Wetzel, and M. C. van Zanten

The second Dynamics and Chemistry of Marine Stratocumulus (DYCOMS-II) field study is described. The field program consisted of nine flights in marine stratocumulus west-southwest of San Diego, California. The objective of the program was to better understand the physics a n d dynamics of marine stratocumulus. Toward this end special flight strategies, including predominantly nocturnal flights, were employed to optimize estimates of entrainment velocities at cloud-top, large-scale divergence within the boundary layer, drizzle processes in the cloud, cloud microstructure, and aerosol–cloud interactions. Cloud conditions during DYCOMS-II were excellent with almost every flight having uniformly overcast clouds topping a well-mixed boundary layer. Although the emphasis of the manuscript is on the goals and methodologies of DYCOMS-II, some preliminary findings are also presented—the most significant being that the cloud layers appear to entrain less and drizzle more than previous theoretical work led investigators to expect.

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