Abstract.We describe observations of tropical stratospheric water vapor q that show clear evidence of large-scale

Halley Bay (75.5øS, 26.8øW) that has occurred annually since the mid-1970s in September and October. This Antarctic ozone "hole" which is characterized by 50% or more decreases in column ozone has now been extensively studied using satellite, aircraft, and ground-based instruments. In addition, further analyses of satellite and ground-based Dobson data have shown northern hemisphere (30øN to 64øN) The Halogen Occultation Experiment (HALOE) was conceived to provide critical data for study of the ozone distribution and those processes which affect ozone levels. The experiment uses the principle of satellite solar occultation to sound the stratosphere, mesosphere, and lower thermosphere. Using this technique, absorption of solar energy in selected spectral bands is used to infer vertical profiles of temperature, pressure, and mixing ratios of key gases involved in the ozone chemistry. The HALOE instrument includes both broadband and gas filter channels Together, these observations form a minimum but adequate set which can be used to derive, under appropriate conditions, the unmeasured concentrations of several other gases needed to test understanding of the chemistry (see Figure 1). In this regard, HALOE 03, H20, and CH4 measurements, for example, can be used to derive OH levels. In turn, these parameters can be used to derive atomic chlorine and, from that, C10 through reactions with 03. Chlorine monoxide can be used with NO2 observations to derive chlorine nitrate (C1ONO2). Since C10

The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) experiment is one of four experiments that will fly on the Thermosphere, Ionosphere, Mesosphere, Energetics, and Dynamics (TIMED) mission to be launched in May, 2000. The primary science goal of SABER is to achieve major advances in understanding the structure, energetics, chemistry, and dynamics, in the atmospheric region extending from 60 km to 1 80 km altitude. This will be accomplished using the space flight proven experiment approach of spectral broadband limb emission radiometry. SABER will scan the horizon in 10 selected bands ranging from 1.27 im to 17 tm wavelength. The observed vertical horizon emission profiles will be processed on the ground to provide vertical profiles with 2 km altitude resolution, of temperature, 03, H20, and CO2 volume emission rates due to O2(1i), OH(u=3,4,5), OH(i=7,8,9), and NO; key atmospheric cooling rates, solar heating rates, chemical heating rates, airglow losses; geostrophic winds, atomic oxygen and atomic hydrogen. Measurements will be made both night and day over the latitude range from the southern to northern polar regions. The SABER instrument uses an on-axis Cassegrain design with a clam shell reimager. Preliminary test and calibration results show excellent radiometric performance.

[1] In this work absolute values of gravity wave (GW) momentum flux are derived from global temperature measurements by the satellite instruments High Resolution Dynamics Limb Sounder (HIRDLS) and Sounding of the Atmosphere using Broadband Emission Radiometry (SABER). Momentum fluxes in the stratosphere are derived for both instruments and for SABER in the whole mesosphere. The large-scale atmospheric background state is removed by a two-dimensional Fourier decomposition in longitude and time, covering even planetary-scale waves with periods as short as 1-2 days. Therefore, it is possible to provide global distributions of GW momentum flux from observations for the first time in the mesosphere. Seasonal as well as longer-term variations of the global momentum flux distribution are discussed. GWs likely contribute significantly to the equatorward tilt of the polar night jet and to the poleward tilt of the summertime mesospheric jet. Our results suggest that GWs can undergo large latitudinal shifts while propagating upward. In particular, GWs generated by deep convection in the subtropical monsoon regions probably contribute significantly to the mesospheric summertime wind reversal at mid-and high latitudes. Variations in the GW longitudinal distribution caused by those convectively generated GWs are still observed in the mesosphere and could be important for the generation of the quasi two-day wave. Indications for quasi-biennial oscillation (QBO) induced variations of GW momentum flux are found in the subtropics. Also variations at time scales of about one 11-year solar cycle are observed and might indicate a negative correlation between solar flux and GW momentum flux.Citation: Ern, M., P. Preusse, J. C. Gille, C. L. Hepplewhite, M. G. Mlynczak, J. M. Russell III, and M. Riese (2011), Implications for atmospheric dynamics derived from global observations of gravity wave momentum flux in stratosphere and mesosphere,

[1] The seasonal and interannual variability of migrating (Sun-synchronous) and nonmigrating solar atmospheric tides at altitudes between 100 and 116 km are investigated using temperature measurements made with the SABER instrument on the TIMED spacecraft during [2002][2003][2004][2005][2006]. Quasi-biennial variations of order ±10-15% in migrating diurnal and semidiurnal tidal amplitudes are found, presumably due to modulation by the quasi-biennial oscillation (QBO) as the tides propagate from their troposphere and stratospheric sources to the lower thermosphere. A number of nonmigrating tidal components are found that have the potential to produce significant longitudinal variability of the total tidal fields. The most prominent of these, i.e., those that appear at amplitudes of order 5-10 K in a 5-year mean climatology, include the zonally symmetric (s = 0) diurnal tide (D0); the eastward propagating diurnal and semidiurnal tides with zonal wave numbers s = À2 (DE2 and SE2) and s = À3 (DE3 and SE3); and the following westward propagating waves: diurnal s = 2 (DW2); semidiurnal s = 1 (SW1), s = 3 (SW3), and s = 4 (SW4); and terdiurnal s = 5 (TW5). These waves can be plausibly accounted for by nonlinear interaction between migrating tidal components and stationary planetary waves with s = 1 or s = 2 or by longitudinal variations of tropospheric thermal forcing. Additional waves that occur during some years or undergo phase cancellation within construction of a 5-year climatology include DW5, SE1, SE4, SW6, TE1, TW1, and TW7. It is anticipated that the winds that accompany all of these waves in the 100-170 km region will impose longitudinal variability in the electric fields produced through the ionospheric dynamo mechanism, thereby modulating vertical motion of the equatorial ionosphere and the concomitant plasma densities. In addition to the wave-4 modulation of the equatorial ionosphere that has recently been discovered and replicated in modeling studies, the waves revealed here will generate wave-1 (SW1, SW3, D0, DW2), wave-2 (SW4, TW1), wave-3 (DE2, SE1), wave-4 (DE3, SE2, DW5, SW6, TE1, TW7), wave-5 (SE3), and wave-6 (SE4) components of this ionospheric variability, depending on year and time of year. However, the absolute and relative efficiencies with which these waves produce electric fields remains to be determined.