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Taubenheim, J.

Publications and source records attributed to Taubenheim, J..

6 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1989

Solar activity influence on climatic variations of stratosphere and mesosphere in mid-latitudes

The direct modulation of temperature of the mid-latitude mesosphere by the solar-cycle EUV variation, which leads to greater heat input at higher solar activity, is well established. Middle atmosphere temperature modulation by the solar cycle is independently confirmed by the variation of reflection heights of low frequency radio waves in the lower ionosphere, which are regularly monitored over about 30 years. As explained elsewhere in detail, these reflection heights depend on the geometric altitude of a certain isobaric surface (near 80 k), and on the solar ionizing Lyman-alpha radiation flux. Knowing the solar cycle variation of Lyman-alpha how much the measured reflection heights would be lowered with the transition from solar minimum to maximum can be calculated, if the vertical baric structure of the neutral atmosphere would remain unchanged. An discrepancy between expected and observed height change must be explained by an uplifting of the isobaric level from solar minimum to maximum, caused by the temperature rise in the mesosphere. By integrating the solar cycle temperature changes over the height region of the middle atmosphere, and assuming that the lower boundary (tropopause) has no solar cycle variation, the magnitude of this uplifting can be estimated. It is given for the Lidar-derived and for the rocket-measured temperature variations. Comparison suggests that the real amplitude of the solar cycle temperature variation in the mesosphere is underestimated when using the rocket data, but probably overestimated with the Lidar data.

Taubenheim, J.↗
NASA NTRS1989

Evidence of CO2-induced progressive cooling of the middle atmosphere derived from radio observations

Reflection heights of low frequency radio waves in midlatitude summer, which are closely associated with the neutral atmosphere isobaric level of 0.0052 hPa, exhibit a statistically significant downgoing trend from 1962 to 1987. This indicates a systematic decrease of air pressure at 80 km height by 10.3 plus or minus 4.9 percent over this period, to be regarded as a sufficient evidence of a true signal of progressive cooling of the middle atmosphere, expected with the growing content of CO2 and other greenhouse bases in the atmosphere. It is quantitatively consistent with a temperature decrease at the stratopause by about 4 K, as predicted by the recent model of interactive greenhouse and ozone processes of Brasseur and de Rudder (1987).

Taubenheim, J.↗
NASA NTRS1989

Observations of, and sources of the spatial and temporal variability of ozone in the middle atmosphere on climatological time scales (OZMAP) and equatorial dynamics: Seasonal variations of ozone trends

The long term trends (least square linear regression with time) of ozone content at seven European, seven North American, three Japanese and two tropical stations during 21 years (1964 to 1984) are analyzed. In all regions negative trends are observed during the 1970s, but are partly compensated by limited periods of positive trends during the late 1960s and late 1970s. Solely the North American ozone data show negative trends in all 10 year periods. When the long term ozone trends are evaluated for each month of the year separately, a seasonal variation is revealed, which in Europe and North America has largest negative trends in late winter and spring. While in Europe the negative trends in winter/spring are partly compensated by positive trends in summer, in North America the summer values reach only zero, retaining the significant negative trend in annual mean values. In contrast to the antarctic ozone hole, the spring reduction of ozone in Europe and in North America is associated with stratospheric temperatures increasing in the analyzed period and therefore is consistent with the major natural ozone production and loss processes.

Entzian, G.↗
NASA NTRS1984

Middle Atmosphere Program. Handbook for MAP, Volume 10

The contributions of ground based investigations to the study of middle atmospheric phenomena are addressed. General topics include diagnostics of the middle atmosphere from D region properties, winter anomaly, seasonal variations and disturbances, dynamics and theoretical models, ground based tracking of winds and waves, lower thermosphere phenomena, and solar-terrestrial influences.

Taubenheim, J.↗
NASA NTRS1984

Neutral Atmosphere Properties Determining D-region Electron Densities

The increasing discoveries of various manifestations of meteorological control of the D region ionization and the growth of techniques for its measurement provide a challenge to meteorologists to test their insight into middle atmosphere processes with the physical interpretation of D layer phenomena. Models for ion production due to photoionization of minor atmospheric nitric oxide by quasi-monochromatic solar Lyman-alpha radiation are presented. A ground based measuring technique using low frequency radio reflection heights is briefly described and an approach to the interpretation of data acquired by this method is discussed. It is shown that D region electron density variations can provide an efficient diagnostic tool for the detection of perturbations of the circulation state of the middle atmosphere.

Taubenheim, J.↗