HR: 1340h
AN: A53D-1438 [Abstracts]
TI: Expanding Curtain Observations of Cloud Vertical Structure and Layering to Model-Relevant Spatial Scales
AU: * Miller, S
EM: miller@cira.colostate.edu
AF: Cooperative Institute for Research in the Atmosphere (CIRA), Foothills Campus
1375 Campus Delivery, Fort Collins, CO 80523-1375, United States
AU: Bankert, R
EM: bankert@nrlmry.navy.mil
AF: Naval Research Laboratory (NRL), 7 Grace Hopper Ave. MS#2, Monterey, CA 93943-5502,
United States
AU: Forsythe, J
EM: forsythe@cira.colostate.edu
AF: Cooperative Institute for Research in the Atmosphere (CIRA), Foothills Campus
1375 Campus Delivery, Fort Collins, CO 80523-1375, United States
AU: Mitrescu, C
EM: mitrescu@nrlmry.navy.mil
AF: Naval Research Laboratory (NRL), 7 Grace Hopper Ave. MS#2, Monterey, CA 93943-5502,
United States
AU: Reinke, D
EM: reinke@cira.colostate.edu
AF: Cooperative Institute for Research in the Atmosphere (CIRA), Foothills Campus
1375 Campus Delivery, Fort Collins, CO 80523-1375, United States
AU: Austin, R
EM: austin@atmos.colostate.edu
AF: Colorado State University (CSU), Atmospheric Science Department
Foothills Campus, Fort Collins, CO 80523, United States
AB:
Clouds, representing perhaps the most obvious physical manifestations of atmospheric dynamics at work,
remain in many ways an enigmatic and unifying intellectual challenge to researchers of all disciplines within the
atmospheric sciences. Given the universally acknowledged importance of cloud systems in determining the state
of current and future climate through radiative, chemical, dynamic, and thermodynamic processes tied intimately
to the hydrological cycle, it is no wonder that so much recent attention has been given to better understanding the
non-linear feedbacks involving clouds and ways to improve their handling in numerical weather prediction (NWP)
models. In terms of operational community interests, knowledge of cloud vertical structure, ceiling (cloud base)
height, and phase is key to aviation safety assurance in the private, commercial, and defense-agency sectors
alike.
The launch of the NASA Earth System Science Pathfinder CloudSat (cloud radar; 3 mm wavelength) mission in
2006 changed forever the way we view cloud systems from the space platform—providing vertically-resolved
‘cuts' through the cloudy troposphere. The Cloud Profiling Radar (CPR) system resolves nearly all radiatively
significant cloud structures present in the column at vertical resolutions sufficient to afford scientists the
opportunity to examine new hypotheses on cloud formation (leading potentially to new/improved cloud process
parameterizations) and make observationally-based discoveries bordering on the frontiers of our current
understanding. At the same time, the non-scanning nature of the CPR (providing so-called ‘curtain' observations)
represents in some respects a frustrating tease to the potential of a three-dimensional scanning system,
relegating its utility to the realms of research as opposed to full spatial environmental characterization and data
assimilation.
This research examines ways to extend via statistical methods the curtain slices provided by CloudSat into the
horizontal to construct pseudo three-dimensional information. These statistics are based on cloud-type
classification, which are identifiable from cloud top observations by conventional 2-D observing systems.
Preliminary cloud-type-dependent vertical structures, based on the CloudSat Level-2 Cloud Water Content (CWC)
product, are presented for an assortment of cloud classifications. Such statistics can then be applied to the
vertically-integrated liquid/ice water content as retrieved by 2-D sensors to distribute this water in the column
according to type-dependency. In addition, the degree to which cloud layer base heights can be extended into the
cross-track direction (e.g., given an observation of similar cloud-type from a conventional 2-D optical radiometer)
can be assessed via correlation lengths computed along the CloudSat track. The effective result is a pseudo 3-D
swath of cloud water content of potential use to operational support and numerical weather prediction analysis
and/or validation. Preliminary results from the currently available compilation of CloudSat data are presented to
illustrate conceptually the potential and limitations of such approaches.
DE: 0320 Cloud physics and chemistry
DE: 3310 Clouds and cloud feedbacks
DE: 3360 Remote sensing
DE: 3394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting