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The weather radar |
WHY TO USE RADAR INFORMATION ?
Many human activities are subjected to pluviometric risks, and to forecast the rain evolution is sometimes essential for economic reasons or for security.
If weather forecasting indicates
with good reliability the weather that it will occur in a few days, tomorrow,
or in twelve hours, a monitoring of the rainfall in real time can be necessary,
as well as the monitoring of the risks of rain in a precise location. It is
the case, for example, for the management of a sewage network or a treatment
plant , a building site or a farm, or a tennis ground.
The weather radar is a privileged
tool to remotely detect and monitor rainy structures. Rainfall can be detected
for ranges exceeding 200 km, and it is possible to anticipate the evolution
of rain on a given point or on average on a basin or an entire region. It
is also possible to estimate rainfall in mm/h, although this estimation can
be affected by significant errors and must be carried out by taking into account
the principal sources of these errors.
Beyond the real time information,
archived radar images can also be of great interest to better understand a
rain event by analysing the rain field behaviour in space and time, and can
bring important information for the assessment of an historical event, or
an event having caused localised damage. Radar images also facilitate the
taking account of the space-time variability of precipitation in hydrological
studies.