Basic Data Assimilation Concepts

Workshop, 11 September 2016, Trieste

Roland Potthast, DWD (Research and Development, Head Division Data Assimilation),


The workshop will provide an introduction to data assimilation concepts, methods and techniques for forecasters and meteorologists.

To calculate weather forecasts on short or longer temporal scales, measurement data need to be fused into a coherent estimate of the current state of the atmosphere. These techniques are also of growing importance for nowcasting, and they are an important ingredient for climate monitoring and to calibrate climate projections. When measurements are integrated into model states, we usually speak of data assimilation.

The workshop provides a basic introduction to the ideas, set-up, properties, techniques and results which are behind data assimilation and data fusion. Its goal is to enable forecasters and users to understand the role of measurements, the capabilities and limitations of assimilation, and to gain insight into the whole NWP system which consists of a data assimilation cycle and forecast runs. A particular focus will be placed on the determination of uncertainty and risk within the analysis and forecast, which is a key goal of modern ensemble data assimilation systems.


09:30 Welcome
09:30 – 10:15 Data assimilation – The big picture,
developing data assimilation from data streams to forecast visualization
10:15 – 11:00 The ideas behind data assimilation
Simple examples to explain how it all works.
11:00 – 11:15 Tea/coffee break
11:15 – 12:15 Global satellite data assimilation: infrared and microwave radiances
polar orbiting satellites, hyperspectral sounders, data features and IR/MW assimilation
12:15 – 13:15 Lunch break
13:15 – 14:00 Convective scale ensemble data assimilation and ensemble prediction
presentation of the Kilometre–Scale Ensemble Data Assimilation System KENDA
14:00 – 14:45 Radar data in data assimilation – from composites to 3D–volume–reflectivity
assimilation via latent heat nudging, radar–forward–operator, 3D–volume assimilation
14:45 – 15:00 Tea/coffee
15:00 – 15:45 Impact estimation: data–to–analysis and data–to–forecast
In what way does a measurement influence the forecast? How do you find out? What does it tell you?
15:45 – 16:30 Questions and answers discussion session – perspectives and applications
16:30 Closing
Target group: Anyone interested in the basic concepts of data assimilation.
Min number of participants: 20
Max number of participants: 25


The registration is closed. Registration fees include catering (coffee breaks and lunch), a copy of the course manual and use of the computer cluster to run the experiments.
Participation is by pre-registration only. The workshop may be cancelled in case of low registration numbers.

Registration deadline: 31 July 2016
Registration fee: Early bird registration (deadline 15 June 2016): 100
Standard registration (deadline 31 July 2016): 125