Abstract. The Copernicus Polar Ice and Snow Topography Altimeter (CRISTAL) mission is one of
six high-priority candidate missions (HPCMs) under consideration by the European
Commission to enlarge the Copernicus Space Component. Together, the
high-priority candidate missions fill gaps in the measurement capability of
the existing Copernicus Space Component to address emerging and urgent user
requirements in relation to monitoring anthropogenic CO2 emissions,
polar environments, and land surfaces. The ambition is to enlarge the
Copernicus Space Component with the high-priority candidate missions in the
mid-2020s to provide enhanced continuity of services in synergy with the
next generation of the existing Copernicus Sentinel missions. CRISTAL will
carry a dual-frequency synthetic-aperture radar altimeter as its primary
payload for measuring surface height and a passive microwave radiometer to
support atmospheric corrections and surface-type classification. The
altimeter will have interferometric capabilities at Ku-band for improved
ground resolution and a second (non-interferometric) Ka-band frequency to
provide information on snow layer properties. This paper outlines the user
consultations that have supported expansion of the Copernicus Space
Component to include the high-priority candidate missions, describes the
primary and secondary objectives of the CRISTAL mission, identifies the key
contributions the CRISTAL mission will make, and presents a concept – as far
as it is already defined – for the mission payload.
The Copernicus Polar Ice and Snow Topography Altimeter (CRISTAL) high-priority candidate mission
