Analysis of microphysical data during aircraft cross over events in VOCALs

The VOCALs field campaign in the South Eastern Pacific, 2008 (Allen & Abel, 2009) collected microphysical and radiometric data on stratocumulus clouds and in particular for this presentation, by the UK FAAM BAe-146 and NERC Dornier 228 aircraft. The Cloud Droplet Probe, (Droplet Measurement Technologies, 2009) aboard the 146 produced droplet size distributions, whilst the Dornier's downward facing Eagle and Hawk hyperspectral imagers (Spectral Imaging Ltd, 2009) reflectances from the stratocumulus cloud deck. In this paper, these data will be compared for overlap events, and used to analyse the relationship between microphysical and radiometric properties; in particular the short wave emissivity of the clouds will be examined.

Data from the Eagle and Hawk hyperspectral imagers can be directly compared with data from the MODIS instrument on the Terra and Aqua satellites by passing the output through the MODIS algorithms. This can give a resolution of 100m for the albedo. In the presentation, these remote sensing data will be enable comparison of albedo paramaterizations applied to the observed microphysical data, e.g. the Schwartz-Slingo parameterisation (Schwartz and Slingo, 1996).

References:

Allen, G. and Abel, S. (2009). VAMOS Ocean-Climate-Atmosphere-Land Study: UK component, Technical report, VOCALS-UK.

Droplet Measurement Technologies (2009). Cloud droplet probe (CDP) manual, Technical report, Droplet Measurement Technologies Inc.

Schwartz, S. E. and Slingo, A. (1996). Enhanced shortwave radiative forcing due to anthropogenic aerosols, in P. Crutzen and V. Ramanathan (eds), Clouds chemistry and climate, Springer, pp. 191- 236.

Spectral Imaging Ltd. (2009). AISA dual eagle and hawk hyperspectral sensor, Technical report, Spectral Imaging Ltd.