Introduction, overview, and status of the NPOESS aerosol polarimetry sensor (APS)

The National Polar-orbiting Operational Environmental Satellite System (NPOESS) added several new aerosol and cloud Environmental Data Records (EDRs) to the NPOESS Integrated Operational Requirements Document (IORD) in 2001 that require procurement of an Aerosol Polarimetry Sensor (APS). The APS provides a unique along-track scan to produce EDRs directly underneath the satellite to estimate climate trends. APS will measure orthogonal polarizations in nine spectral bands between 0.4 and 2.4 μm and will be launched on the first NPOESS operational satellite planned for 2009 in a 2130 local ascending node time orbit. The APS contractor was selected in early 2003 for a fall 2003 contract start. This paper describes the APS requirements and provides an overview of the design approach.