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Science Definition Team

NASA selected a Science Definition Team (SDT) in 2012 to guide the development of science requirements for NISAR for a period of three years.

A new solicitation for the SDT for the second three-year period was announced in March 2015, supporting Phase B and Phase C activities and selections were announced in April of 2016.

From 2012-2015, the SDT created a set of compelling and achievable science requirements, which in turn were used by the NISAR project team to scope the mission concept for the Mission Concept Review, held in October 2013, and to establish a rigorous connection between the requirements on the space and ground segments of the mission and the science, as presented at the Science Requirements Review (SRR) and Mission Design Review (MDR) held in December 2014. Success in these reviews has allowed the project to enter Phase B, or late formulation, where the designs of the system are laid out in greater detail in preparation for the flight system development. In supporting SRR/MDR, the SDT worked closely with scientists and engineers associated with the project to establish performance models for each of the science requirements, and show that NISAR as designed and conceived to operate could meet the requirements.
The continuing role of the SDT in Phase B is to define in greater specificity the data products and science algorithms that will used to validate the science requirements during operations, develop a detailed plan for requirements validation, and to validate the performance models developed in Phase A to add extra confidence in using the models for requirements verification during development. The current SDT has created detailed plans for Phase B activities focused on the following tasks:
  1. Define science data products (“L2-L4” in data product parlance) that will be used for validating Level 1 and Level 2 science requirements. These descriptions will be in terms of product type and measurement variables, as opposed to formats. The timeframe for this activity is March-September 2015.
  2. Define the science algorithms that would be used to create these science data products. The description of the algorithms will be in sufficient detail that code could be written to create the defined science product from existing analogous data (without any requirement to meet NISAR accuracy requirements) by coding the algorithms. The timeframe for this activity is March-September 2015, with algorithms implemented by January 2016 if needed for validation activities.
  3. Write first version of Algorithm Theoretical Basis Document (ATBD) for each product. The ATBD’s will be written in sufficient detail that an independent team of developers could implement the algorithms in code without significant direction from the SDT. First draft in Winter 2016. Final Draft in Summer 2016.
  4. Validate performance models used to set the requirements and evaluate whether trade studies represent reality. The setting of requirements and demonstration of their achievability has relied on a global performance simulation developed by the NISAR project with SDT input. In this task, the SDT will use existing data and planned algorithms and show that the performance tool, when given appropriate inputs for the available data, yields accuracy estimates that are observed in the data. The activity will kick off in Spring 2015, with performance tool enhancements delivered in Summer 2015, and assessments based on data analysis in Spring and Summer 2016.
  5. Participate in the 2nd applications workshop. The first workshop was held in October 2014, with good SDT participation. It is anticipated that the SDT will again contribute to the second workshop. Applications workshops are to be held every year; the 2nd workshop is being planned for October 2015.
  6. Conduct discipline-specific Calibration/Validation workshops, if deemed appropriate. Each discipline has different levels of algorithm maturity and needs for calibration and validation during science operations. Each discipline will decide if a Cal/Val workshop is needed to develop a comprehensive and concrete Cal/Val program for NISAR. The dates for the workshop are not yet specified, but likely to be held in Autumn 2015 or early 2016.
  7. Develop discipline-specific Calibration/Validation plans, with associated costs. Informed by workshops and other community deliberations, the SDT will develop plans that can be provided to the NISAR project to integrate into a comprehensive project plan. The plan is due in Spring 2016 in advance of the Preliminary Design Review (PDR), which is scheduled for August 2016.
Phase C activities will be defined later in Phase B. Phase C will begin after PDR, which is scheduled for August 2016.

2016 Science Definition Team Members

  • Cathleen Jones, Jet Propulsion Laboratory (Applications Lead)
  • Ian Joughin, Applied Physics Lab, U Washington (Dynamics of Ice Lead)
  • Mark Simons, Caltech (Solid Earth Deformation Lead)
  • Paul Siqueira, U Massachusetts (Ecosystems Lead)
  • Falk Amelung, U Miami
  • Adrian Borsa, Scripps Institution of Oceanography
  • Bruce Chapman, JPL
  • Eric J Fielding, JPL
  • Richard Forster, U Utah
  • Bradford H. Hager, MIT
  • Ben Holt, JPL
  • Josef Kellndorfer, Earth Big Data, Inc.
  • Ronald Kwok, JPL
  • Zhong Lu, Southern Methodist University
  • Franz Meyer, U Alaska, Fairbanks
  • Frank Monaldo, NOAA
  • Rowena Lohman, Cornell University
  • Eric Rignot, UC Irvine
  • Sassan Saatchi, JPL
  • Marc Simard, JPL
  • Howard Zebker, Stanford University