OSSE Steering Group: Terms of Reference

Draft, 12/21/2008

Lars Peter Riishojgaard, Director, JCSDA

1Introduction

One of the most important and most difficult problems facing funding agencies responsible for the development and deployment of new space-borne sensors and missions for earth observations is the assessment of often disparate claims concerning the expected impact on applications and science of the proposed new system. Over the coming decades, both NASA and NOAA will face many important decisions on future observing systems. The NRC-led Decadal Survey is proposing a range of missions to NASA and NOAA, most of which are expected to undergo some form of objective impact assessment before final decisions on implementation will be made. NOAA is responsible for civilian side of the nation’s operational meteorological satellite programs and has an interest in ensuring maximum societal benefits are obtained from its investment in these programs.

Over the last 10 to 15 years, Observing System Simulation Experiments (OSSE; e.g., Atlas, 1997, Masutani et al., 2006) have become widely accepted as the de facto standard for assessing the impact on numerical weather prediction (NWP) applications of new candidate missions and systems.

The fact that they are widely used and relied upon does not mean that OSSE systems – or the experimental results created by them – are free of controversy. Because of the wide-ranging consequences of decisions on major space systems, any material on which these decisions are based will have to withstand intense scrutiny and criticism. In recognition of this fact, we propose to help create a national OSSE capability of which both the ownership and oversight is shared among a broad group of stakeholders in future observing systems.

2Rationale for NASA/NOAA OSSE Steering Group

Over the last two years, an informal NWP OSSE collaboration – the so-called Joint OSSE - has developed between scientists from a number of NASA and NOAA groups, including GMAO, EMC, STAR and GSD, with substantial involvement also from the external research community in the US and various international partners. A state-of-the-art Nature Run has been made available free of charge by the ECMWF and the Joint OSSE group has performed an extensive validation and is now embarking on observations simulations and calibration experiments.

While the scope of the work undertaken by the Joint OSSE group is in line with oft-stated requirements of NASA and NOAA/NESDIS, the collaboration as such has developed without any official mandate or oversight. At this point (November 2008), the collaboration is maturing rapidly and it is expected that the first “real” OSSE – i.e. studies of candidate future observing systems for NWP – can be performed in early 2009. In order to help bring some programmatic oversight to the Joint OSSE work, to facilitate coordination between the participating organizations, and to help identify resources where needed, we propose to form an NWP OSSE Steering Group with representatives from NASA, NOAA and the Joint Center for Satellite Data Assimilation. This Steering Group should operate under a mandate from the NASA and NOAA JCSDA Memorandum of Agreement (MOA) signatories and report to that group.

3Responsibilities

The responsibility of the NWP OSSE Steering Group is to:

  • Provide oversight of the Joint OSSE collaboration
  • Lead the development of a comprehensive OSSE plan taking into account NOAA and NASA requirements and priorities
  • Seek and propose avenues for funding the Joint OSSE work
  • Review experimental results from the Joint OSSE work to interpret the information for NASA, NOAA, and interested international collaborators
  • Report to the NASA and NOAA JCSDA MOA signatories on a regular basis

4Membership

The members of the OSSE Steering Group should be representatives of senior management in JCSDA, GMAO, NCEP, NESDIS/STAR and OAR. The following initial membership is proposed:

JCSDA Director (or alternate)

EMC Director (or alternate)

GMAO Head (or alternate)

NESDIS/STAR Director (or alternate)

AOML Director (or alternate)