[1] Thermosphere, Ionosphere, Mesosphere, Energetics, and Dynamics (TIMED)/ Sounding of the Atmosphere Using Broadband Emission Radiometry (SABER) observations of vertical profiles of the OH nightglow emission rates, temperature, and ozone are used along with a theoretical model of the OH nightglow to distinguish the dominant mechanism for the nightglow. From the comparison between the model fit and the observations we conclude that the chemical reaction O 3 + H→ OH(v ≤ 9) + O 2 leads to population distributions of vibrationally excited states that are consistent with the measurements. The contribution of the reaction HO 2 + O→ OH(v ≤ 6) + O 2 to the nightglow is not needed to reproduce the measurements above 80 km, at least for the emissions originating from vibrational transitions with v ≥ 4. The analysis also determines the best fits for quenching of OH(v) by O 2 and O. The results show that the quenching rate of OH(v) by O 2 is smaller and that the removal by O is larger than currently used for the analysis of SABER data. The rate constant for OH(v) quenching by O 2 decreases with temperature in the mesopause region. The vertical profiles of atomic oxygen and hydrogen retrieved using both 2.0 and 1.6 mm channels of Meinel band emission of the OH nightglow and the new quenching rates are slightly smaller than the profiles retrieved using only the 2.0 mm channel and the quenching rate coefficients currently used for the analysis of SABER data. The fits of the model to the observations were also used to evaluate two other assumptions. The assumption of sudden death quenching of OH by O 2 and N 2 (i.e., quenching to the ground state rather than to intermediate vibrational levels) leads to poorer agreement with the SABER observations. The question of whether the reaction with or quenching by atomic oxygen depends on the OH vibrational level could not be resolved; assumptions of vibrational level dependence and independence both gave good fits to the observed emissions.Citation: Xu, J., H. Gao, A. K. Smith, and Y. Zhu (2012), Using TIMED/SABER nightglow observations to investigate hydroxyl emission mechanisms in the mesopause region,

[1] Using TIMED/SABER observations, we present global distribution of the semiannual oscillation (SAO), annual oscillation (AO), and quasi-biennial oscillation (QBO) in the OH nightglow peak emission rate and height as well as the intensity. The latitudinal variations of the SAO, AO, and QBO in the peak emission rate are similar to those in the intensity. For the peak emission rate and the intensity, the SAO and QBO amplitudes have three peaks (one at the equator and others at about 35°S and 35°N). The AO amplitude peaks at about 20°S and 20°N, respectively. The SAO phase is delayed poleward from the equinoxes at the equator to the solstices at 50°S/N; in addition, the phases of the AO are delayed poleward from 30°S. For the peak height, the SAO and QBO amplitudes have three peaks (around the equator, 40°S, and 40°N). Its AO amplitudes at 50°S and 50°N are larger than those at other latitudes; the phase of the SAO shifts from the solstice at the equator to near the equinoxes at 50°S/N. The airglow QBO is stronger in tropics than midlatitude and is likely the real QBO oscillation at the equator. In addition, the emission in the Southern Hemisphere is weaker than that in the Northern Hemisphere. The SAO and QBO are hemispherically symmetrical, and the AO is hemispherically antisymmetrical at some latitudes. The peak emission rate and peak height SAOs are generally in antiphase. The peak emission rate and intensity SAOs are generally in phase.Citation: Gao, H., J. Xu, and Q. Wu (2010), Seasonal and QBO variations in the OH nightglow emission observed by TIMED/ SABER,

In this work, 11 years (2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012) of Thermosphere, Ionosphere, Mesosphere Energetics, and Dynamics/Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) global temperature data are used to study the nonlinear interaction between stationary planetary waves (SPWs) and tides in the stratosphere and mesosphere. The holistic behavior of the nonlinear interactions between all SPWs and tides is analyzed from the point of view of energetics. The results indicate that the intensities of nonmigrating diurnal, semidiurnal, terdiurnal, and 6 h tides are strongest during winter and almost vanish during summer, synchronous with SPW activity. Temporal correlations between the SPWs and nonmigrating tides for these four tidal components are strong in the region poleward of 20°and below about 80 km. In the tropics, where the SPWs are very weak in all seasons, the correlations are small. Bispectral analysis between triads of waves and tides shows which particular interactions are likely to be responsible for the generation of the nonmigrating tides that are largest in the midlatitude stratosphere. Based on the more limited SABER observations at high latitudes, the correlations there are similar to those in midlatitudes during spring, summer, and autumn; there are no high-latitude observations by SABER in winter. These results show that nonlinear interactions between SPWs and tides in the stratosphere and the lower mesosphere may be an important source of the nonmigrating tides that then propagate into the upper mesosphere and lower thermosphere.

[1] Airglow from the hydroxyl Meinel bands, originating from about 87 km, gives a signature of the atmosphere that can be observed remotely. Analysis of long term global observations of the 2.0 mm OH Meinel brightness observed by the TIMED/SABER satellite instrument presents some striking patterns that appear in the Meinel airglow. The analysis shows that migrating and nonmigrating tides have large effects on the nighttime OH airglow emission in the upper mesosphere. The OH airglow emission rate is positively correlated with temperature below 94 km and negatively correlated above. Variations with longitudinal wavenumbers 1 and 4 are shown to result from the impacts of the stationary (D0), westward wavenumber 2 (DW2), and eastward wavenumber 3 (DE3) nonmigrating diurnal tides. Citation:

Culturally protected forests (CPFs), preserved and managed by local people on the basis of traditional practices and beliefs, have both social and ecological functions. We investigated plant species richness and diversity within the tree layer, shrub layer and herb layer in three types of CPFs (community forests, ancestral temple forests, cemetery forests) as well as nearby forests without cultural protection (NCPFs) in Southeast China. A total of 325 species belonging to 85 families and 187 genera were recorded in CPFs, including 17 protected species in China Species Red List and IUCN Red List, which accounted for 17 % of counties' endangered species. Compared with NCPFs, the tree layer of CPFs had larger DBH and lower species density, especially in the cemetery forests. CPFs had higher alpha diversity values generally, particularly in the tree layer. The differences in tree layer were substantial, and CPFs covered nearly 85.4 % of the tree species in the surveyed sites. The similarities between CPFs and NCPFs were higher in the herb and shrub layers than in the tree layer. These differences of species diversity may be attributed to differences in resource use and management between CPFs and NCPFs. Our field investigation results suggested that local CPFs harbor many plant species, high biodiversity, and contribute to the conservation of a substantial proportion of the local species pool.

[1] In this paper, observations by thermosphere, ionosphere, mesosphere energetics and dynamics/Sounding of the Atmosphere using Broadband Emission Radiometry from 2002 to 2012 and by Envisat/Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) from 2008 to 2009 are used to study the longitudinal structure of temperature in the lower thermosphere. In order to remove the longitudinal structure induced by tides, diurnally averaged SABER temperatures are used. For MIPAS data, we use averaged temperatures between day and night. The satellite observations show that there are strong longitudinal variations in temperature in the high-latitude lower thermosphere that persist over all seasons. The peak of the diurnally averaged temperature in the lower thermosphere always occurs around the auroral zone. A clear asymmetry between the two hemispheres in the longitudinal temperature structure is observed, being more pronounced in the Southern than in the Northern Hemisphere. In both hemispheres, the longitudinal variation is dominated by the first harmonic in longitude. The total radiative cooling observed by SABER has a structure in longitude that is similar to that of temperature. Modeling simulations using the Thermosphere-Ionosphere-Electrodynamics General Circulation Model reproduce similar features of the longitudinal variations of temperature in the lower thermosphere. Comparison of two model runs with and without auroral heating confirms that auroral heating causes the observed longitudinal variations. The multiyear averaged vertical structures of temperature observed by the two satellite instruments indicate that the impact of auroral heating on the thermodynamics of the neutral atmosphere can penetrate down to about 105 km.

[1] This study uses the GRACE (Gravity Recovery And Climate Experiment) and CHAMP (CHAllenging Minisatellite Payload) accelerometer measurements from 2003 to 2008. These measurements gave thermospheric mass densities at~480 km (GRACE) and~380 km (CHAMP), respectively. We found that there are strong longitude variations in the daily mean thermospheric mass density. These variations are global and have the similar characteristics at the two heights under geomagnetically quiet conditions (Ap < 10). The largest relative longitudinal changes of the daily mean thermospheric mass density occur at high latitudes from October to February in the Northern Hemisphere and from March to September in the Southern Hemisphere. The positive density peaks locate always near the magnetic poles. The high density regions extend toward lower latitudes and even into the opposite hemisphere. This extension appears to be tilted westward, but mostly is confined to the longitudes where the magnetic poles are located. Thus, the relative longitudinal changes of the daily mean thermospheric mass density have strong seasonal variations and show an annual oscillation at high and middle latitudes but a semiannual oscillation around the equator. Our results suggest that heating of the magnetospheric origin in the auroral region is most likely the cause of these observed longitudinal structures. Our results also show that the relative longitude variation of the daily mean thermospheric mass density is hemispherically asymmetric and more pronounced in the Southern Hemisphere.Citation: Xu, J., W. Wang, and H. Gao (2013), The longitudinal variation of the daily mean thermospheric mass density,

Abstract. This paper presents the thermal forcing of the semidiurnal, terdiurnal, and 6-h components of the migrating tide induced by ozone heating in stratosphere and lower mesosphere. The heating as a function of local time is determined from the global ozone observed by the Microwave Limb Sounder on the Aura satellite. The harmonic components of the heating rates of the semidiurnal, terdiurnal and the 6-h periodicities are calculated using the Strobel/Zhu parameterized model and then decomposed into Hough modes. Seasonal variations of each harmonic component and its Hough modes are presented. For all three tidal components, the majority of the annual mean O 3 heating projects onto symmetric modes. The semiannual variation is a prominent signal in almost all of the symmetric Hough modes near the stratopause. The strongest annual variation takes place in the asymmetric modes. The results also show that, during the solstice season, the maximum forcing of the diurnal and terdiurnal component occurs in the summer hemisphere while the maximum forcing of the semidiurnal and 6-h components occurs in the winter hemisphere. The global mean ozone density and the tidal components of the ozone heating rate are different between December-January and June-July. The asymmetry in the heating is primarily due to the 6.6 % annual variation in the solar energy input into the Earth's atmosphere due to the annual variation of the Sun-Earth distance.