Topic: Observation impact

Friday, November 4, 2022 from 07-09 UTC

Organizers and Conveners: Nikki Privé (Morgan State University/NASA/GSFC, US), Daisuke Hotta (JMA, Japan), Hristo Chipilski (NCAR, US), Tobias Necker (University of Vienna, Austria)

Knowledge of the influence of observations is crucial for improving observing, data assimilation and forecasting systems. Today, a large variety of instruments provides millions of observations per day and the number of observations is steadily increasing. However, only a limited amount of these measurements can be assimilated due to algorithmic, computational, and research limitations. All this calls for better methods for estimating the actual and potential impact of observations. This session aims to discuss different aspects of observation impact assessment such as the results from recent OSSE and FSOI studies as well as new observational and methodological developments. We are looking forward to your contributions!

Program / Abstracts (PDF Download)

Session recordings (RIKEN website)

Questions asked during the event (Yopad)


  • Running Ensemble of Data Assimilation Experiments – using GNSS-RO and MW sounding data
    Katrin Lonitz, Sean Healy, Katie Lean, Niels Bormann (live presentation)
  • Seasonality of the impact of stratospheric observations at high latitudes
    Bruce Ingleby, Inna Polichtchouk (live presentation)
  • Impacts of Assimilating Infrared Sounders from Geostationary Orbit
    Erica L. McGrath-Spangler, Nikki C. Privé, Bryan M. Karpowicz, Isaac Moradi, Joel McCorkel, Will McCarty (pre-recorded talk)
  • Ensemble Forecast Sensitivity to Observations Impact (EFSOI) applied to a regional data assimilation system over Argentina
    Gimena Casaretto, Maria Eugenia Dillon, Yanina Garcia Skabar, Juan Ruiz (pre-recorded talk)
  • Using ensemble sensitivities to estimate the benefit of wind lidars
    Philipp Griewank, Ulrich Löhnert, Tobias Necker, Tatiana Nomokonova, Takemasa Miyoshi, Martin Weissmann (live presentation)
  • Covariance based impact diagnostics for cross-validating the consistent use of different observation types
    Olaf Stiller (live presentation)

Time Zones:
09 UTC
Europe:            07 – 09 am GMT (London)      | 08 – 10 am CET (Berlin)
Asia/Australia: 03 – 05 pm CST (Shanghai)   | 04 – 06 pm JST (Tokyo)      | 06 – 08 pm AEDT (Sydney)
Americas:        00 – 02 am PDT (San Fran.)  | 01 – 03 am MDT (Denver)   | 03 – 05 am EDT (New York)

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