NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Observations and Modeling of Composition of Upper Troposphere/Lower Stratosphere (UTILS): Isentropic Mixing Events and Morphology of HNO3 as Observed by HIRDLS and Comparison with Results from Global Modeling Initiativeisentropic exchange of air masses between the tropical upper troposphere and mid-latitude lowermost stratosphere (the so-called "middle world") is an important pathway for stratospheric-tropospheric exchange. A seasonal, global view of this process has been difficult to obtain, in part due to the lack of the vertical resolution in satellite observations needed to capture the laminar character of these events. Ozone observations at a resolution of about 1 km from the High Resolution Dynamic Limb Sounder (HIRDLS) on NASA's Aura satellite show instances of these intrusions. Such intrusions should also be observable in HN03 observations; however, the abundances of nitric acid could be additionally controlled by chemical processes or incorporation and removal into ice clouds. We present a systematic examination of the HIRDLS data on O3 and HNO3 to determine the seasonal and spatial characteristics of the distribution of isentropic intrusions. At the same time, we compare the observed distributions with those calculated by the Global Modeling Initiative combined tropospheric-stratospheric model, which has a vertical resolution of about I km. This Chemical Transport Model (CTM) is driven by meteorological fields obtained from the GEOS-4 system of NASA/Goddard Global Modeling and Assimilation Office (GMAO), for the Aura time period, at a vertical resolution of about 1 km. Such comparison brings out the successes and limitations of the model in representing isentropic stratospheric-tropospheric exchange, and the different processes controlling HNO3 in the UTAS.
Document ID
20080037983
Acquisition Source
Goddard Space Flight Center
Document Type
Preprint (Draft being sent to journal)
Authors
Rodriquez, J. M.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Douglass, A.R.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Yoshida, Y.
(Maryland Univ. Baltimore County Baltimore, MD, United States)
Strahan, S.
(Maryland Univ. Baltimore County Baltimore, MD, United States)
Duncan, B.
(Maryland Univ. Baltimore County Baltimore, MD, United States)
Olsen, M.
(Maryland Univ. Baltimore County Baltimore, MD, United States)
Gille, J.
(National Center for Atmospheric Research Boulder, CO, United States)
Yudin, V.
(National Center for Atmospheric Research Boulder, CO, United States)
Nardi, B.
(National Center for Atmospheric Research Boulder, CO, United States)
Date Acquired
August 24, 2013
Publication Date
January 1, 2008
Subject Category
Meteorology And Climatology
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available