OSEs, OSSEs and the NOSIA Capability

NOAA spends approximately ($2.7B) annually to develop, acquire, and operate operational and research-oriented earth observing systems. Due to budgetary pressures and the increasing cost and complexity of earth observations, the question of which systems or combination of systems provide the greatest value has become paramount. To address this question, NOAA has developed a best-in-breed observing system portfolio analysis capability.

Observing system experiments (OSEs) are important in determining the impact of various earth observing systems on a numerical weather prediction (NWP) model. Observing system simulation experiments (OSSEs) are critical in examining future observing system impacts or changes in configuration on an NWP system. While an OSE or OSSE provides a quantitative analysis of observing system impacts for a single model, the effects on products that rely on that model can only be estimated qualitatively. Additionally, the observational impacts due to observing system configuration changes cannot be gauged concurrently across a suite of weather prediction models (such as those at the NCEP Environmental Modeling Center).

The second NOAA Observing System Integrated Analysis (NOSIA-II) study recently surveyed subject matter experts across all of NOAA to quantitatively gauge the impacts of the current Earth observation portfolio on the key products and services that define NOAA's core mission. These products include both operational and research weather prediction models. Since NOSIA also examined how these models feed into other NOAA products, there exists the capability to quantitatively assess impacts of observing system changes and model improvements on those products that depend on NWP output. Consequently, the NOSIA analysis process could become an important complement of the NOAA Quantitative Observing System Assessment Program (QOSAP).