An assessment of the impact of antishattering tips and artifact removal techniques on bulk cloud ice microphysical and optical properties measured by the 2D cloud probe

Abstract

A recent study showed that the ratio of the number of distribution functions derived from 2D cloud probes (2DCs) with standard tips to those with antishatter tips used during the 2008 Indirect and Semidirect Aerosol Campaign (ISDAC) and Instrumentation Development and Education in Airborne Science 2011 (IDEAS-2011) was greater than 1 for ice crystals with maximum dimension D <500 μm. To assess the applicability of 2DC data obtained without antishatter tips previously used in parameterization schemes for numerical models and remote sensing retrievals, the impacts of artifacts on bulk microphysical and scattering properties were examined by quantifying differences between such properties derived from 2DCs with standard and antishatter tips, and with andwithout the use of shatter detection algorithms using the ISDACand IDEAS-2011 data. Using eithermodified tips or algorithms changed the quantities dominated by higher-order moments, such as ice water content, bulk extinction, effective radius, mass-weighted terminal velocity, median mass diameter, asymmetry parameter, and single-scatter albedo, at wavenumbers from 5 to 100 cm-1 and wavelengths of 0.5-5μm by less than 20%. This is significantly less than the fractional changes quantities dominated by lower-order moments, such as number concentration. The results suggest that model parameterizations and remote sensing techniques based on higherorder moments of ice particle size distributions obtained in conditions similar to those sampled during IDEAS-2011 and ISDAC derived from 2DCs are not substantially biased by shattered remnants.