ROMUALD1, the new weather radar at the Guiana Space Centre (CSG), Europe’s spaceport, will be
unveiled to the press at the Montagne des Pres on Monday 22 October 2001 by Philippe Courtier,
Assistant Director General of METEO-FRANCE (the French national weather service), and Pierre
Moskwa, CNES/CSG Director, accompanied by Fernando Doblas, representing the European Space
Agency in French Guiana. It will then be inaugurated at the Rochambeau weather centre.

A joint CNES/METEO-FRANCE project

ROMUALD, which will replace the RODIN radar currently in service, is designed to meet the CSG
launch base’s increasingly exacting needs. It will provide METEO-FRANCE with essential data to
enhance its weather forecasting capability in French Guiana, under a ten-year partnership
agreement with CNES. ROMUALD will form part of a network2 of nine radars that by 2004 will cover
the Greater Caribbean and enable more accurate prediction of heavy rainfall and cyclones.

This vital project for operations at the CSG weather office was co-funded to the tune of Û1.67
million by the European Space Agency (ESA) and CNES, including an equipment subsidy of
Û410,000 from METEO-FRANCE. CNES’s DLA/SDS3 sub-directorate was prime contractor in charge of
the operation, responsible for site assessment, specifications and installation. CNES/CSG will
operate and maintain the radar, assisted by METEO-FRANCE.

ROMUALD – a precious ally

Due to its proximity to the Equator, French Guiana is subjected during the rainy season4 to intense
precipitation that can cause extensive damage. During the dry season5, which is the cyclone
season along the Antilles island arc, atmospheric instabilities bring storms accompanied by heavy
showers all over the country. For example, heavy rain in April 2000 led to flooding and on 19 April
to a landslide on Mont Cabassou that claimed ten lives.

Located atop the Montagne des Pres some 60 kilometres from Cayenne, the new radar will cover
populated coastal areas from Saint Laurent to the Brazilian border, including the CSG and Saint
Georges. It will provide forecasters at the METEO-FRANCE centre based at Cayenne-Rochambeau
airport with precipitation data every five minutes. Such data are essential for atmospheric
observation and very-short-term weather forecasting. The new radar will also be able to detect
intense precipitation events earlier and thus give populations one to two hours’ more warning. It
will have the capability to detect dangerous phenomena within a radius of 150 to 200 kilometres
and to measure precipitation within a radius of 100 to 120 kilometres.

Data from the new radar will help the CNES/CSG weather office to establish weather forecasts for
Ariane launches and all other high-risk operations at the launch base. Weather officers in launch
operations teams study and estimate weather parameters for each launch, concentrating

their attention mainly on ground and air lightning, and wind force and direction on the ground at
various points. They also need to forecast and track precipitation and wind (direction,
instantaneous velocity and mean velocity over 10 minutes) close to launch base sites where
dangerous operations are to be performed. The CSG’s processing system also includes a
decision-support tool called GSF able to estimate the speed and direction of movement of the main
cloud masses and to extrapolate their position over the next one or two hours.

Lastly, METEO-FRANCE will use the radar data to assist water resource managers. Meteorological
data concerning precipitation duration and intensity are vital to municipal engineering departments
and specialist firms in charge of managing water resources and networks, i.e., storm water
treatment networks, river flood control works, surface runoff and dams. METEO-FRANCE has
developed a system called ASPIC able to track precipitation and storms over two hours for
monitoring catchment basins and urban areas.

The new ROMUALD radar at the Grand Leblond site atop the Montagne des Pres will be operated
round the clock by CNES/CSG weather office teams, who will relay data to the METEO-FRANCE
Rochambeau centre.



Dominique Dago / Jean-Pierre Lemarchand TŽl : 05

94 28 21 53 / TŽl : 05 96 63 99 63

Marie-Pierre Joseph-Alberton / Mireille Clabault
TŽl : 05
94 33 57 95 / TŽl : 05 94 33 32 67