Four-dimensional variational assimilation

{
  "id": "MLC-T-MET-005737",
  "term": "Four-dimensional variational assimilation",
  "field": "Meteorology and atmospheric science",
  "definition": "An advanced data assimilation technique that minimizes a cost function representing the misfit between a numerical model forecast and observations over a time interval, typically 6 to 24 hours. It uses the adjoint of the forecast model to efficiently calculate the gradient of the cost function with respect to the initial state. This method provides a dynamically consistent analysis of the atmospheric state.",
  "url": "https://mlchart.com/terminology/meteorology/four-dimensional-variational-assimilation/"
}