NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
The middle atmospheric response to short and long term solar UV variations: analysis of observations and 2D model resultsWe have investigated the middle atmospheric response to the 27-day and 11-yr solar UV flux variations at low to middle latitudes using a two-dimensional photochemical model. The model reproduced most features of the observed 27-day sensitivity and phase lag of the profile ozone response in the upper stratosphere and lower mesosphere, with a maximum sensitivity of +0.51% per 1% change in 205 nm flux. The model also reproduced the observed transition to a negative phase lag above 2 mb, reflecting the increasing importance with height of the solar modulated HO(x) chemistry on the ozone response above 45 km. The model revealed the general anti-correlation of ozone and solar UV at 65-75 km, and simulated strong UV responses of water vapor and HO(x) species in the mesosphere. Consistent with previous 1D model studies, the observed upper mesospheric positive ozone response averaged over +/- 40 was simulated only when the model water vapor concentrations above 75 km were significantly reduced relative to current observations. In agreement with observations, the model computed a low to middle latitude total ozone phase lag of +3 days and a sensitivity of +0.077% per 1% change in 205 nm flux for the 27-day solar variation, and a total ozone sensitivity of +0.27% for the 11-yr solar cycle. This factor of 3 sensitivity difference is indicative of the photochemical time constant for ozone in the lower stratosphere which is comparable to the 27-day solar rotation period but is much shorter than the 11-yr solar cycle.
Document ID
19950055652
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Fleming, Eric L.
(Applied Research Corp. Landover, MD, United States)
Chandra, Sushil
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Jackman, Charles H.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Considine, David B.
(Applied Research Corp. Landover, MD, United States)
Douglass, Anne R.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
August 16, 2013
Publication Date
March 1, 1995
Publication Information
Publication: Journal of Atmospheric and Terrestrial Physics
Volume: 57
Issue: 4
ISSN: 0021-9169
Subject Category
Geophysics
Accession Number
95A87251
Distribution Limits
Public
Copyright
Other

Available Downloads

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