@misc{78762,
  keywords = {workshop, data assimilation, diagnostics, systems performance},
  author = {R. Gelaro and R. Todling and R. Langland and Y. Trémolet},
  title = {Recent developments in the use and understanding of adjoint-derived estimates of observation impact},
  year = {2009},
  month = {2009},
  url = {https://www.ecmwf.int/node/15263},
  language = {eng},
}