During the forthcoming decade and beyond there will be a plethora of
global space-based active and passive measurements of cirrus and ice
cloud. These measurements will be across the electromagnetic spectrum,
from the ultra-violet to the far-infrared, through to the
sub-millimeter, where there are no current radiance observations in the
latter spectral regions. To take advantage of these unprecedented
high-resolution and spectral-like measurements, ice crystal models are
required that are physically consistent throughout the electromagnetic
spectrum, and which are consistent with microphysics assumptions in
weather and climate models. Achieving such physical consistency between
ice crystal models, remote-sensing, and large-scale models to meet the
challenges posed by the forthcoming measurements over the next decade or
so is problematic. However, it is necessary to overcome this difficulty
to improve the predictive quality of weather and climate models to
address extreme weather events and climate change, respectively.
However, cirrus and ice cloud types consist of ice crystals that vary
considerably both in shape and size between the cloud top and bottom.
Not surprisingly, with such variability in the shapes and sizes,
obtaining models that are coherent across the spectrum while at the same
time being consistent with microphysics assumptions in weather and
climate models is difficult. In this talk, to address the above issues,
an approach using an ensemble model of cirrus ice crystals to predict
consistently the observed radiative properties of cirrus from the
ultra-violet to the far-infrared will be discussed using aircraft and
satellite-based high-resolution radiance measurements. In this analysis,
different shapes of the particle size distribution are utilized that are
consistent with a weather and climate model, remote-sensing, and with an
in-situ mass power law. Here, the need for improved simultaneous in-situ
and aircraft remote-sensing spectral characterization of cirrus across
the electromagnetic spectrum will be emphasized. Moreover, an example of
the development of a new ice crystal model that follows in-situ ice
crystal mass and area power laws, which are consistent with a weather
and climate model is described, with some preliminary results, to help
address the radiative issues.