Search Results

You are looking at 1 - 4 of 4 items for :

  • Author or Editor: Jean-Pierre Chaboureau x
  • Bulletin of the American Meteorological Society x
  • Refine by Access: All Content x
Clear All Modify Search
Noëlle A. Scott
,
Alain Chédin
,
Raymond Armante
,
Jennifer Francis
,
Claudia Stubenrauch
,
Jean-Pierre Chaboureau
,
Frederic Chevallier
,
Chantal Claud
, and
Frédérique Cheruy

From 1979 to present, sensors aboard the NOAA series of polar meteorological satellites have provided continuous measurements of the earth's surface and atmosphere. One of these sensors, the TIROS-N Operational Vertical Sounder (TOVS), observes earth-emitted radiation in 27 wavelength bands within the infrared and microwave portions of the spectrum, thereby creating a valuable resource for studying the climate of our planet. The NOAA–NASA Pathfinder program was conceived to make these data more readily accessible to the community in the form of processed geophysical variables. The Atmospheric Radiation Analysis group at the Laboratoire de Météorologie Dynamique of the Centre National de la Recherche Scientifique of France was selected to process TOVS data into climate products (Path-B). The Improved Initialization Inversion (3I) retrieval algorithm is used to compute these products from the satellite-observed radiances. The processing technique ensures internal coherence and minimizes both observational and computational biases. Products are at a 1° × 1° latitude–longitude grid and include atmospheric temperature profiles (up to 10 hPa); total precipitable water vapor and content above four levels up to 300 hPa; surface skin temperature; and cloud properties (amount, type, and cloud-top pressure and temperature). The information is archived as 1-day, 5-day, and monthly means on the entire globe; a.m. and p.m. products for each satellite are stored separately. Eight years have been processed to date, and processing continues at the rate of approximately two satellite-months per day of computer time. Quality assessment studies are presented. They consist of comparisons to conventional meteorological data and to other remote sensing datasets.

Full access
Paola Formenti
,
Barbara D’Anna
,
Cyrille Flamant
,
Marc Mallet
,
Stuart John Piketh
,
Kerstin Schepanski
,
Fabien Waquet
,
Frédérique Auriol
,
Gerard Brogniez
,
Frédéric Burnet
,
Jean-Pierre Chaboureau
,
Aurélien Chauvigné
,
Patrick Chazette
,
Cyrielle Denjean
,
Karine Desboeufs
,
Jean-François Doussin
,
Nellie Elguindi
,
Stefanie Feuerstein
,
Marco Gaetani
,
Chiara Giorio
,
Danitza Klopper
,
Marc Daniel Mallet
,
Pierre Nabat
,
Anne Monod
,
Fabien Solmon
,
Andreas Namwoonde
,
Chibo Chikwililwa
,
Roland Mushi
,
Ellsworth Judd Welton
, and
Brent Holben

Abstract

The Aerosol, Radiation and Clouds in southern Africa (AEROCLO-sA) project investigates the role of aerosols on the regional climate of southern Africa. This is a unique environment where natural and anthropogenic aerosols and a semipermanent and widespread stratocumulus (Sc) cloud deck are found. The project aims to understand the dynamical, chemical, and radiative processes involved in aerosol–cloud–radiation interactions over land and ocean and under various meteorological conditions. The AEROCLO-sA field campaign was conducted in August and September of 2017 over Namibia. An aircraft equipped with active and passive remote sensors and aerosol in situ probes performed a total of 30 research flight hours. In parallel, a ground-based mobile station with state-of-the-art in situ aerosol probes and remote sensing instrumentation was implemented over coastal Namibia, and complemented by ground-based and balloonborne observations of the dynamical, thermodynamical, and physical properties of the lower troposphere. The focus laid on mineral dust emitted from salty pans and ephemeral riverbeds in northern Namibia, the advection of biomass-burning aerosol plumes from Angola subsequently transported over the Atlantic Ocean, and aerosols in the marine boundary layer at the ocean–atmosphere interface. This article presents an overview of the AEROCLO-sA field campaign with results from the airborne and surface measurements. These observations provide new knowledge of the interactions of aerosols and radiation in cloudy and clear skies in connection with the atmospheric dynamics over southern Africa. They will foster new advanced climate simulations and enhance the capability of spaceborne sensors, ultimately allowing a better prediction of future climate and weather in southern Africa.

Full access
Cyrille Flamant
,
Jean-Pierre Chaboureau
,
Julien Delanoë
,
Marco Gaetani
,
Cédric Jamet
,
Christophe Lavaysse
,
Olivier Bock
,
Maurus Borne
,
Quitterie Cazenave
,
Pierre Coutris
,
Juan Cuesta
,
Laurent Menut
,
Clémantyne Aubry
,
Angela Benedetti
,
Pierre Bosser
,
Sophie Bounissou
,
Christophe Caudoux
,
Hélène Collomb
,
Thomas Donal
,
Guy Febvre
,
Thorsten Fehr
,
Andreas H. Fink
,
Paola Formenti
,
Nicolau Gomes Araujo
,
Peter Knippertz
,
Eric Lecuyer
,
Mateus Neves Andrade
,
Cédric Gacial Ngoungué Langué
,
Tanguy Jonville
,
Alfons Schwarzenboeck
, and
Azusa Takeishi

Abstract

During the boreal summer, mesoscale convective systems generated over West Africa propagate westward and interact with African easterly waves, and dust plumes transported from the Sahel and Sahara by the African easterly jet. Once off West Africa, the vortices in the wake of these mesoscale convective systems evolve in a complex environment sometimes leading to the development of tropical storms and hurricanes, especially in September when sea surface temperatures are high. Numerical weather predictions of cyclogenesis downstream of West Africa remains a key challenge due to the incomplete understanding of the clouds–atmospheric dynamics–dust interactions that limit predictability. The primary objective of the Clouds–Atmospheric Dynamics–Dust Interactions in West Africa (CADDIWA) project is to improve our understanding of the relative contributions of the direct, semidirect, and indirect radiative effects of dust on the dynamics of tropical waves as well as the intensification of vortices in the wake of offshore mesoscale convective systems and their evolution into tropical storms over the North Atlantic. Airborne observations relevant to the assessment of such interactions (active remote sensing, in situ microphysics probes, among others) were made from 8 to 21 September 2021 in the tropical environment of Sal Island, Cape Verde. The environments of several tropical cyclones, including Tropical Storm Rose, were monitored and probed. The airborne measurements also serve the purpose of regional model evaluation and the validation of spaceborne wind, aerosol and cloud products pertaining to satellite missions of the European Space Agency and EUMETSAT (including the Aeolus, EarthCARE, and IASI missions).

Open access
Luiz A. T. Machado
,
Maria A. F. Silva Dias
,
Carlos Morales
,
Gilberto Fisch
,
Daniel Vila
,
Rachel Albrecht
,
Steven J. Goodman
,
Alan J. P. Calheiros
,
Thiago Biscaro
,
Christian Kummerow
,
Julia Cohen
,
David Fitzjarrald
,
Ernani L. Nascimento
,
Meiry S. Sakamoto
,
Christopher Cunningham
,
Jean-Pierre Chaboureau
,
Walter A. Petersen
,
David K. Adams
,
Luca Baldini
,
Carlos F. Angelis
,
Luiz F. Sapucci
,
Paola Salio
,
Henrique M. J. Barbosa
,
Eduardo Landulfo
,
Rodrigo A. F. Souza
,
Richard J. Blakeslee
,
Jeffrey Bailey
,
Saulo Freitas
,
Wagner F. A. Lima
, and
Ali Tokay

CHUVA, meaning “rain” in Portuguese, is the acronym for the Cloud Processes of the Main Precipitation Systems in Brazil: A Contribution to Cloud-Resolving Modeling and to the Global Precipitation Measurement (GPM). The CHUVA project has conducted five field campaigns; the sixth and last campaign will be held in Manaus in 2014. The primary scientific objective of CHUVA is to contribute to the understanding of cloud processes, which represent one of the least understood components of the weather and climate system. The five CHUVA campaigns were designed to investigate specific tropical weather regimes. The first two experiments, in Alcantara and Fortaleza in northeastern Brazil, focused on warm clouds. The third campaign, which was conducted in Belém, was dedicated to tropical squall lines that often form along the sea-breeze front. The fourth campaign was in the Vale do Paraiba of southeastern Brazil, which is a region with intense lightning activity. In addition to contributing to the understanding of cloud process evolution from storms to thunderstorms, this fourth campaign also provided a high-fidelity total lightning proxy dataset for the NOAA Geostationary Operational Environmental Satellite (GOES)-R program. The fifth campaign was carried out in Santa Maria, in southern Brazil, a region of intense hailstorms associated with frequent mesoscale convective complexes. This campaign employed a multimodel high-resolution ensemble experiment. The data collected from contrasting precipitation regimes in tropical continental regions allow the various cloud processes in diverse environments to be compared. Some examples of these previous experiments are presented to illustrate the variability of convection across the tropics.

Full access