As an example, ECMWF uses 4D - Variational data assimilation techniques to optimally combine an astounding amount of satellite and conventional data over a given window in time. (dotearth.blogs.nytimes.com)
Our proposed framework, together with Data Assimilation techniques, allows developing, testing, and optimizing measures and policies that can be implemented in practice for early detection of critical or extreme conditions that will lead to major risks to society and failure of supporting systems and infrastructure, and aid in the estimation of irreversible thresholds or regime - shifting tipping points [211,212,, 213]. (academic.oup.com)
He has been working on the predictability studies using radiosonde observations and data assimilation technique. (polarprediction.net)