Cirrus and Anvils: European Satellite and Airborne Radiation measurements project




Daily Diary

Summaries and briefs

Satellite Overpasses

Instrument Status


Chilbolton directions



CAESAR is a field campaign designed to understand the radiative properties of cirrus cloud over a wide range of wavelengths in combination with airborne in situ measurements of cirrus microphysical properties. Flights using the FAAM BAe-146 will measure frontal and anvil cirrus, co-incident with the CloudSat Aqua-train, SEVERI and AATSR satellites over the Chilbolton cloud radars and lidars as well as ocean/sea surrounding the UK. Aircraft measurements will be used to obtain vertical profiles of ice crystal size, shape and IWC and how these quantities vary in the horizontal direction so that a good statistical sampling is obtained representative of the cirrus microphysical state. Measurements will be made at different times of the year to observe the different types of cirrus clouds.

Scientific aims:

  • To improve the representation of cirrus clouds in Numerical Weather Prediction and Climate Studies.
  • To perform closure studies relating the cloud microphysics to remote sensing data across the visible, thermal infrared, far infrared and microwave regions of the electromagnetic spectrum.
  • To validate remotely sensed products from the A-Train, AATSR, Seviri and Chilbolton Radar.


There are 4 phases to CAESAR:

CAESAR I - Nov/Dec 2005, simultaneously with MICROMIX

CAESAR II - April/May 2006, simultaneously with VISURB-UK and ICEPIC

CAESAR III - Nov/Dec 2006/Jan 07, simultaneously with IASI and WINTEX

CAESAR IV - July 2007, simultaneously with VISURB-UK and Land-emiss