Bienvenue sur la page d'accueil ChArMEx - The Chemistry-Aerosol Mediterranean Experiment Fri, 09 Sep 2016 12:47:13 +0000 Joomla! 1.5 - Open Source Content Management en-gb 5th ChArMEx International Workshop - Larnaca October 17-21


]]> (ehamonou) frontpage Thu, 23 Jun 2016 15:38:14 +0000
ChArMEx Student awarded at the 7th International PTR-MS Conference 2016 Congrats to Nora Zannoni, a former ChArMEx Student now POSTDOC at LSCE, who was awarded BEST POSTER at the 7th International PTR-MS Conference 2016!

Nora Zannoni presented a poster on her work on OH reactivity in the frame of ChArMEx. Total OH reactivity is the total loss of the hydroxyl radical OH due to atmospheric reactive gases. Measurements of total OH reactivity help to quantify the total loading of reactants in ambient air.

She was able to show that about 45% of OH destruction (during daytime) was due to reactants emitted by the Mediterranean vegetation! Indeed, under intense sunlight, high temperatures and soil dryness, the vegetation becomes an important emitter of organic gases (Volatile Organic Compounds) that react with OH. 

More astonishingly, she reports that 50% of OH loss remained unexplained showing that some reactive chemical species present in the Mediterranean atmosphere are still unknown and need to be identified!

7th International PTR-MS Conference Official Award (left) and Nora Zannoni's poster (right).



OH reactivity at a Mediterranean coastal site
Nora Zannoni1, Valerie Gros1, Roland Sarda1, Bernard Bonsang1, Cerise Kalogridis1, Sebastien Dusanter2,3,4, Vincent Michoud2,3, Nadine Locoge2,3, Stephane Sauvage2,3, Aurelie Colomb5, Sophie Szopa1.
1 LSCE, (CNRS-CEA-UVSQ), Gif sur Yvette, France.
2 SAGE, MINES DOUAI, Douai, France
3University Lille, Villeneuve d'Ascq, France
4 School of Public and Environmental Affairs, Indiana University, Bloomington, IN, USA
5 LAMP (CNRS), Clermont Ferrand, France


]]> (Hamonou) frontpage Wed, 10 Jun 2015 12:55:29 +0000
ChArMEx Student awarded at EGU 2015 Congrats to Pierre Nabat, a former ChArMEx/HyMEX PhD Student now researcher at CNRM, who was awarded OUTSTANDING STUDENT POSTER at the EGU 2015 General Assembly!

First study of its kind in the Mediterranean

Pierre Nabat presented a poster on his work on the impact of aerosols on the mediterranean climate. He was able to show the importance of this impact thanks to a new original approach consisting of a full coupling of the atmospheric and ocean models.  

EGU Official Award (left) and Pierre Nabat's poster (right).


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ChArMEx Student awarded at SOLAS International Conference Congrats to Camille Richon, a ChArMEx/MerMex PhD Student, who was awarded BEST POSTER at the SOLAS Open Science Conference 2015!

SOLAS (Surface Ocean Lower Atmosphere Study) is an international and interdisciplinary research project on biogeochemical-physical air-sea interactions and processes. Its last International Conference was held in September in Kiel (Germany) and gathered about 260 scientists from 35 countries.

Camille Richon presented a poster on her work which concerns the modelisation of the impact of dust deposition on the biogeochemical processes and the primary production of the Mediterranean sea.

SOLAS Official Award (left) and Camille Richon's poster (right).


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ChArMEx Science - Atmospheric Conveyor belt dumps Indian Pollution in the Mediterranean

Two International teams one led by researchers from Météo France/CNRM/GAME ( and the other one led by researchers from the UPEC/CNRS/LISA ( have identified new proofs of the existence of an atmospheric conveyor belt dumping Indian produced pollution into the Eastern Mediterranean basin!

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Methane mixing ratio (left) and ozone concentration (right) derived from IASI spaceborne instrument showing a clear west-east gradient with higher levels of pollutants over the Eastern Mediterranean

Teams have been looking at time-series of satellite measurements of greenhouse gases (ozone and methane) and found systematic maximum of summer concentrations over the Eastern Mediterranean. Something was adding greenhouse gases creating a steep west-east gradient of concentrations.To find out what was this mechanism state-of-art computer models capable of simulating both the atmospheric circulation and the chemical transport as well as meteorological analyses have been used. It turned out that these simulations pointed at the Asian Monsoon!


How a typical Asian Monsoon Meteorological results in conveying Indian Pollution to the Mediterranean

The Asian Monsoon traps and uplifts high amounts of methane and ozone that are then transported towards North Africa and Middle East by the Asian Monsoon Anticyclone to finally reach and descent in the Eastern Mediterranean basin.

Contact: (Methane study) (Ozone study)

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]]> (Hamonou) frontpage Thu, 30 Jul 2015 15:31:41 +0000
ChArMEx Science - Aerosols decrease rain and increase heat waves intensity ChArMEx and HyMeX show that aerosols over the Mediterranean dry its atmosphere and increase the intensity of heat waves

A team from CNRM (Toulouse, France), LA (Toulouse, France), ICTP (Trieste, Italy)  and the ETH Zurich (Switzerland) has recently published ( the results of regional climate simulations with an atmosphere-ocean coupled model accounting for radiative effects of aerosols on solar and thermal infrared radiation, showing that aerosols over the Mediterranean basin tend to reduce precipitation and strengthen the intensity of heat waves.


Rain intensity difference with aerosols (AER) or without (NO) in forced mode (F) (left) and coupled mode (C) (right) (Nabat et al., 2014)


The Mediterranean atmosphere is heavily loaded with aerosols especially during spring and summer. Because aerosol particles scatter incident solar radiation, part of it will never reach the surface. In addition, some aerosols (especially soot carbon and Saharan dust) absorb solar radiation and heat the atmospheric layers where they are present. Thus, aerosols have a tendency to significantly reduce the amount of energy that reaches the surface, reducing surface temperature and water evaporation, and to increase the air temperature of turbid layers, reducing the cloud cover. On an annual average the reduction in precipitation reaches 0.2 mm/day over the Mediterranean basin, which represents about 10% of the annual average. Besides, because of induced changes on atmospheric dynamics, it was found that African dust aerosol increased by 0.5°C (~15%) a heat wave observed in July 2006. These aerosol impacts are attenuated in atmospheric only climate models that use a prescribed sea-surface temperature

The first author of this study, Pierre Nabat from CNRM, has been awarded the André Prudhomme 2015 prize by the Société Météorologique de France for his outstanding PhD performed in the framework of HyMeX and ChArMEx and that includes this study.


]]> (Hamonou) frontpage Thu, 04 Jun 2015 13:08:43 +0000
ChArMEx Science - Less aerosols bring more light and more heat to Europe! ChArMEx and HyMEx show that less sulfate aerosols over Europe has brought more light and more heat to the Europeans.

A team from CNRM, LA, the University of Girona (Spain) and the ETH Zurich (Switzerland) has recently published ( the results of a new kind of modelisation showing that sulfate aerosols reduction over Europe since 1980ies mostly explains the brightening of Europe surface that has been measured since then.

Sulfate aerosols standing in mid-air act has sunshades that reflects sunlight to the outer space. The reduction of the number of such sunshades since the 1980ies due to the set-up of emission control policies in Europe has thus had 2 sides effects: it has brought more light to the Europeans and brought more heat!



Model vs Measurements (colored circles) for (left) the surface solar radiation trend (W/m2/decade) for 1980-2007, and (right) the temperature trend (°C/decade) at 2 m for 1980-2007



]]> (Hamonou) frontpage Fri, 22 May 2015 09:08:27 +0000
MISTRALS International Conference, Marseille (France), Oct. 20-22 2015) mistrals

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ChArMEx Science - Improving Air Quality simulations ChArMEx shows how LIDAR measurements can improve air quality simulations

A team from LSCE and CEREA has recently published ( the results of a new experiment showing how a network of ground-based LIDARS can improve the forecasting of the concentration levels of fine particles (PM2.5 and PM10). Results show that the LIDAR data assimilation has improved PM10 concentration forecast by up to almost 10% for PM10 in France and Spain.


 LIDAR network

Their approach is based on the so-called data assimilation method which is commonly used for improving weather forecasting models. LIDAR observations are assimilated in the course of data production in order to improve air quality forecast. Using LIDAR measurement enables models to take into account the pollution that is transported at altitude as well as pollution locally emitted. It thus gives a more suitable constraint for improving the forecast.      

dust event assimil

The method has been tested during a major dust event (see image above) that occured during the ChArMEx/TRAQA campaign in July 2012. This was the first time ever that data assimilation was implemented in air quality model. The model was fed by the vertical distribution of aerosols obtained thanks to a network of 10 LIDARS (from the ACTRIS/EARLINET network and from CORSiCA) spread all over southern Europe.  

This work is part of the PhD thesis of Yiguo Wang who got a grant from CEA and EDF and was co-chaired by Patrick Chazette from LSCE and Karine Sartelet from  CEREA (EDF R&D et Ecole des Ponts Paris Tech).

Contact :

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