Subject: ROSES-15 Amendment 18: Delay of due dates for A.34 SCIS ROSES-15 Amendment 18: The due dates for program element A.34 Satellite Calibration Interconsistency Studies, have been delayed. Notices of Intent (NOIs) are now requested by October 14, 2015 and proposals are now due by December 8, 2015. The quantitative determination of global trends in the Earth’s atmosphere, ocean, cryosphere, biosphere, and land surface depends significantly on the ability of the scientific community to construct multiinstrument/multiplatform data sets based on satellite observations covering periods of a decade or longer. This effort, global in scope, also constitutes a global challenge, as most if not all such data sets will rely on satellite programs from multiple agencies and/or nations, in particular, requiring both the use of satellites primarily focused on research and the use of those intended for operations. This ROSES element provides an opportunity for the research community to participate in the quantitative comparison of multiple satellite data products to facilitate the development of multiinstrument/multiplatform data sets involving satellites from multiple providers. Proposals responsive to this call MUST address interconsistency issues of two or more satellites, at least one of which must be one currently supported through NASA’s Earth Science Program, and at least one of which must be supported by some other organization (U.S. or foreign). NOIs are now requested by October 14, 2015 and proposals are now due by December 8, 2015. On or about June 9, 2015, this Amendment to the NASA Research Announcement "Research Opportunities in Space and Earth Sciences (ROSES) 2015" (NNH15ZDA001N) will be posted on the NASA research opportunity homepage at http://nspires.nasaprs.com/ and will appear on the RSS feed at: http://nasascience.nasa.gov/researchers/sara/grant-solicitations/roses-2015 Questions concerning this program element may be directed to: Lucia Tsaoussi at lucia.s.tsaoussi@nasa.gov.