The Relationship Between Composite Cirrus Morphology and Large-Scale Meteorology Derived from 94-GHz Cloud Radar Data

While it is generally recognized that clouds play an important role in the climate system, many fundamental cloud properties have not been extensively observed. Clouds can be described on multiple spatial and temporal scales. At the largest scales, the patterns of cloud systems denote synoptic scale motions. These patterns are, however, strongly modulated by mesoscale atmospheric motions and individual cloud elements exist and are maintained by turbulence coupled to cloud microphysical processes. It is the microphysical characteristics of clouds that have been most extensively studied, largely by the use of instrumented aircraft. This is particularly true in recent years with the First International Satellite Cloud Climatology Project Regional Experiment (FIRE), International Cirrus Experiment (ICE), and EUCREX field campaigns. While thoroughly understanding the microphysical mechanisms important to the smallest spatial and temporal scales is critical, recent field experiments have not adequately quantified the macroscopic characteristics of clouds or their variability. Beyond this, the relationship of both the microphysical and macrophysical cloud characteristics to the meso-synoptic atmospheric state is still largely undetermined from data. For example, there exists very little published literature simultaneously documenting the occurrence of multiple cloud layers, cloud base height, cloud top height, and internal cloud structure. This is not surprising since all conventional cloud observational methodologies are restricted to some degree by the natural variability of cloud occurrence coupled with the limitations of the observing systems.