HR: 1340h
AN: A13C-1370 [Abstracts]
TI: Measured Radiative Properties of Thin Cirrus During TC4
AU: * Bucholtz, A
EM: anthony.bucholtz@nrlmry.navy.mil
AF: Naval Research Laboratory, 7 Grace Hopper Avenue, Monterey, CA 93943, United States
AU: Hlavka, D
EM: Dennis Hlavka [sgdlh@agnes.gsfc.nasa.gov]
AF: Science Systems and Applications, Inc. (SSAI) NASA/Goddard Space Flight Center, Bldg
#33, Greenbelt, MD 20771, United States
AU: McGill, M
EM: Matthew McGill [Matthew.J.McGill@nasa.gov]
AF: NASA-Goddard Space Flight Center
Laboratory For Atmospheres, Bldg 33, Greenbelt, MD 20771, United States
AU: Pilewskie, P
EM: peter.pilewskie@lasp.colorado.edu
AF: Laboratory for Atmospheric and Space Physics, University of Colorado, Duane Physics
Building
Campus Box 311, Boulder, CO 80309, United States
AU: Reid, E A
EM: reidb@nrlmry.navy.mil
AF: Naval Research Laboratory, 7 Grace Hopper Avenue, Monterey, CA 93943, United States
AU: Schmidt, S
EM: K Sebastian Schmidt [sebastian.schmidt@lasp.colorado.edu]
AF: Laboratory for Atmospheric and Space Physics, University of Colorado, Duane Physics
Building
Campus Box 311, Boulder, CO 80309, United States
AU: Walker, A L
EM: annette.walker@nrlmry.navy.mil
AF: Naval Research Laboratory, 7 Grace Hopper Avenue, Monterey, CA 93943, United States
AB:
Thin, often subvisible, cirrus clouds are very common in the tropics but their importance to the radiative budget,
their effect on stratosphere-troposphere exchange, and their formation and persistence mechanisms are still
uncertain. Here we will present direct measurements of the heating rates of tropical thin cirrus in order to gain
insight into whether the absorption of radiative energy contributes to the lifting and persistence of these clouds.
During TC4, measurements of the upwelling and downwelling broadband infrared irradiance and spectral solar
irradiance were made from both the NASA ER-2 aircraft flying above the cirrus and the NASA DC-8 aircraft flying
below the cirrus. This data will be used to derive the heating and cooling rates of the thin cirrus, while
downlooking cloud lidar measurements from the ER-2 will be used to detect their presence, altitude, thickness,
and estimated optical depth. We will focus on two case study days from TC4, the 25July2007 flight, where the
ER-2 attempted to fly a descent profile through a thin cirrus layer, and the 6Aug2007 flight where the ER-2 flew
above a thin cirrus layer while the DC-8 flew below.
DE: 0321 Cloud/radiation interaction
DE: 0360 Radiation: transmission and scattering
DE: 3359 Radiative processes
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting