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There are several groups all working within the Numerical Weather
Prediction area of the Met Office, all with the ultimate aim of
improving the numerical model that is used to forecast the weather;
this in turn increases the accuracy of the forecasts that are issued.
The model may be improved by better numerical techniques and representation
of the atmosphere, by making better use of existing observations
or by developing new observation types. |
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Numerical modelling is the representation of the atmosphere by a computer
model. By improving the model, more accurate weather forecasts can be
produced. Within this area you may learn more about the numerical model,
how physical processes are represented and how we produce operational
weather forecasts.
More about numerical
modelling
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| How observations are used |
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Observations are crucial to weather forecasting. Many thousand are received
each day and these are processed, quality controlled and monitored.
Within this area you may learn more about different observation types,
the daily coverage and the processing that is performed before they
are used. Another aspect is rerunning forecasts to determine what effect
particular observations had.
More about how observations
are used
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| Data analysis and assimilation |
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After observations have been processed and quality controlled they then
need to be incorporated, or assimilated, into the numerical model. In
doing this very important process, we get a representation of the current
state of the atmosphere, i.e. an analysis, from which a forecast is
obtained.
More about data analysis
and assimilation
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Perhaps one of the greatest developments in weather forecasting over
the past 40 years has been the development of weather satellites. A
satellite image of current cloud conditions is a familiar sight on TV
weather forecasts but there is far more to satellite data than simply
producing photographs. Here you will learn about the many ways that
satellite data are used from an ever-growing range of instrumentation.
More about satellite
applications
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| Observational based research |
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The observational based research is based on data from two facilities;
an aircraft and a large range of surface-based instrumentation
including a tethered kite balloon. Both the aircraft and the balloon
are heavily equipped with instrumentation for determining standard
meteorological parameters and more-specialised instrumentation
for measuring turbulence, cloud, aerosol, radiation and chemistry.
More about observational based research
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| Atmospheric processes and parametrizations |
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Many of the physical processes that occur within the atmosphere are
at a scale too small to be directly resolved by weather forecasting
or climate models. Therefore, numerical representations of significant
effects of these processes must be developed: we call these representations
'parametrizations'. In order to parametrize the processes we need
to understand them. We do this by undertaking research using observations
and very-high-resolution numerical models.
More about atmospheric
processes and parametrizations
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Typically, a numerical weather prediction model is only run once from
a given set of initial conditions to produce a single forecast. However,
despite the vast improvements in NWP models over the years, large
errors may still occur even over relatively short forecast ranges.
This is due to the chaotic nature of the atmosphere which means that
a small error in the initial conditions may lead to a large error
in the subsequent forecast, the so called 'butterfly effect'. Because
we can never know the exact truth of the initial conditions, there
will always be a degree of uncertainty in the resulting forecast.
To combat this, an ensemble suite of forecasts may be run with each
forecast having slightly different initial conditions to reflect the
uncertainty. The resulting forecasts may be studied and the possible
range of different scenarios evaluated. This may be used to calculate
a probability for a particular forecast sequence.
More about ensemble forecasts
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Some of the work performed is in conjunction with other meteorological
services or other research institutions. Occasionally, the Met Office
hosts international conferences or workshops.
More about external
collaboration
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Much of the work is written up in technical notes and some is published
in various journals. A quarterly newsletter NWP Gazette is also
produced and an annual Scientific and Technical Review is published
alongside the Met Office Annual Report and Accounts.
More about publications
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