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Ramon Campos Braga
and
Daniel Alejandro Vila

Abstract

This study focuses on the possible relationship between ice water path (IWP) retrievals using high-frequency channels (89 and 150 GHz) from the Advanced Microwave Sounding Unit-B and Moisture Humidity Sounder sensors (NOAA-16NOAA-19) and the life cycle stage of convective clouds. In the first part of this study, the relationship between IWP and the cloud area expansion rate is analyzed using the 235-K isotherm from Geostationary Operational Environmental Satellite-12 (GOES-12) thermal infrared images (10.7 μm). Next, the relationships between cloud convective fraction, rain rates (from ground radar), and cloud life cycle are analyzed. The selected area and time period coincide with the research activities of the Cloud Processes of the Main Precipitation Systems in Brazil: A Contribution to Cloud Resolving Modeling and to the Global Precipitation Measurement (CHUVA)–Geostationary Lightning Mapper (GLM) project at São José dos Campos, Brazil. The results show that 84% of precipitating clouds contain ice, according to the Microwave Surface and Precipitation Products System (MSPPS) algorithm. Convective systems in the intensifying stage (when the area is expanding and the minimum temperature is decreasing) tend to have larger IWPs than systems in the dissipating stage. Larger rain rates and convective fractions are also observed from radar retrievals in the early stage of convection compared with mature systems. Hydrometeor retrieval data from polarimetric X-band radar suggest that particle effective diameter D e and IWP patterns inferred with the MSPPS algorithm could be used to determine the life cycle stage of a given convective system. Using this information, a new set of equations is evaluated for rainfall retrievals using D e and IWP from the current retrieval algorithm. This new approach outperforms the current algorithm in the studied region.

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Manfred Wendisch
,
Ulrich Pöschl
,
Meinrat O. Andreae
,
Luiz A. T. Machado
,
Rachel Albrecht
,
Hans Schlager
,
Daniel Rosenfeld
,
Scot T. Martin
,
Ahmed Abdelmonem
,
Armin Afchine
,
Alessandro C. Araùjo
,
Paulo Artaxo
,
Heinfried Aufmhoff
,
Henrique M. J. Barbosa
,
Stephan Borrmann
,
Ramon Braga
,
Bernhard Buchholz
,
Micael Amore Cecchini
,
Anja Costa
,
Joachim Curtius
,
Maximilian Dollner
,
Marcel Dorf
,
Volker Dreiling
,
Volker Ebert
,
André Ehrlich
,
Florian Ewald
,
Gilberto Fisch
,
Andreas Fix
,
Fabian Frank
,
Daniel Fütterer
,
Christopher Heckl
,
Fabian Heidelberg
,
Tilman Hüneke
,
Evelyn Jäkel
,
Emma Järvinen
,
Tina Jurkat
,
Sandra Kanter
,
Udo Kästner
,
Mareike Kenntner
,
Jürgen Kesselmeier
,
Thomas Klimach
,
Matthias Knecht
,
Rebecca Kohl
,
Tobias Kölling
,
Martina Krämer
,
Mira Krüger
,
Trismono Candra Krisna
,
Jost V. Lavric
,
Karla Longo
,
Christoph Mahnke
,
Antonio O. Manzi
,
Bernhard Mayer
,
Stephan Mertes
,
Andreas Minikin
,
Sergej Molleker
,
Steffen Münch
,
Björn Nillius
,
Klaus Pfeilsticker
,
Christopher Pöhlker
,
Anke Roiger
,
Diana Rose
,
Dagmar Rosenow
,
Daniel Sauer
,
Martin Schnaiter
,
Johannes Schneider
,
Christiane Schulz
,
Rodrigo A. F. de Souza
,
Antonio Spanu
,
Paul Stock
,
Daniel Vila
,
Christiane Voigt
,
Adrian Walser
,
David Walter
,
Ralf Weigel
,
Bernadett Weinzierl
,
Frank Werner
,
Marcia A. Yamasoe
,
Helmut Ziereis
,
Tobias Zinner
, and
Martin Zöger

Abstract

Between 1 September and 4 October 2014, a combined airborne and ground-based measurement campaign was conducted to study tropical deep convective clouds over the Brazilian Amazon rain forest. The new German research aircraft, High Altitude and Long Range Research Aircraft (HALO), a modified Gulfstream G550, and extensive ground-based instrumentation were deployed in and near Manaus (State of Amazonas). The campaign was part of the German–Brazilian Aerosol, Cloud, Precipitation, and Radiation Interactions and Dynamics of Convective Cloud Systems–Cloud Processes of the Main Precipitation Systems in Brazil: A Contribution to Cloud Resolving Modeling and to the GPM (Global Precipitation Measurement) (ACRIDICON– CHUVA) venture to quantify aerosol–cloud–precipitation interactions and their thermodynamic, dynamic, and radiative effects by in situ and remote sensing measurements over Amazonia. The ACRIDICON–CHUVA field observations were carried out in cooperation with the second intensive operating period of Green Ocean Amazon 2014/15 (GoAmazon2014/5). In this paper we focus on the airborne data measured on HALO, which was equipped with about 30 in situ and remote sensing instruments for meteorological, trace gas, aerosol, cloud, precipitation, and spectral solar radiation measurements. Fourteen research flights with a total duration of 96 flight hours were performed. Five scientific topics were pursued: 1) cloud vertical evolution and life cycle (cloud profiling), 2) cloud processing of aerosol particles and trace gases (inflow and outflow), 3) satellite and radar validation (cloud products), 4) vertical transport and mixing (tracer experiment), and 5) cloud formation over forested/deforested areas. Data were collected in near-pristine atmospheric conditions and in environments polluted by biomass burning and urban emissions. The paper presents a general introduction of the ACRIDICON– CHUVA campaign (motivation and addressed research topics) and of HALO with its extensive instrument package, as well as a presentation of a few selected measurement results acquired during the flights for some selected scientific topics.

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