Met Office Cardington: cloud height measurements from a Impulsphysik LD40 Laser Ceilometer, 2010-2014

The Met Office Observation-based research Boundary Layer Facility, at the semi-rural field site (18 Ha) of Cardington (52° 06′ N, 00° 25′ W, 29 m ± 1 m amsl) in central-southern England between 2004 and 2024, operated the Impulsphysik LD40 Ceilometer between 2009-2014.

The LD40 Laser Ceilometer is a general-purpose cloud height sensor employing LIDAR technology for detection of clouds, precipitation and other obstructions to vision. The LD40 operates according to the Light Detection and Ranging (LIDAR) principle. It transmits short pulses of laser light which are scattered back to the instrument from atmospheric targets. The distance of the targets from the instrument is determined by the time delay between the transmission and reception of a pulse. The instrument is vertically-pointing (zenith angle=0) and so the distance gives a measure of the altitude of the targets above ground-level.

The LD40 provides reliable determination of cloud height up to 13 km. It is designed to detect up to three possible cloud layers.

A full list of NetCDF variables can be found in “A continuous hydrometeorological record (2004–2024) at the Met Office surface site of Cardington, UK.” Osborne et al. (2025). This paper should be referenced in any research/publications pertaining to this dataset.

To ensure optimal traceability and transparency of data, comprehensive metadata is included.