Spatial transport and spectral transfer of solar wind turbulence composed of Alfvén waves and convective structures II: numerical results

This work follows the paper titled “Spatial transport and spectral transfer of solar wind turbulence composed of Alfvén waves and convective structures I: The theoretical model”, and deals with the detailed physics and numerical solution of a two-component solar wind model, consisting of small-scale Alfvén waves and convected structures. In particular, we present numerical results which qualitatively reflect many of the observed features of the radial and spectral evolution of the turbulent energies, the residual energy, the cross-helicity and Alfvén-ratio in high-speed solar wind streams. These features are the following: the formation of a characteristic “inclined eye”, which evolves between the energy spectra displayed over the frequency axis and tends to close in the radial development of the spectra, a steepening of all spectra towards Kolmogorov-like f^-5/3 spectra, the development of the normalized cross-helicity towards a constant not much less than one and the formation of a “trough” form of the Alfvén ratio with a z-shaped left boundary, By weighting special terms in the equations differently, we can also cast light on the physical role of parametric conversion model terms, wave-structure scattering model terms, nonlinear terms, spherical expansion terms and their effects on the radial evolution of turbulent energies in high-speed solar wind streams.     

The distribution of acetaldehyde in the lower troposphere during TROPOZ II

A series of 72 measurements of the acetaldehyde (CH₃CHO) mixing ratio were made in the lower troposphere during TROPOZ II. These measurements are the first ever made of the background level of this trace gas in the free troposphere. The data show a vertical decrease of the CH₃CHO mixing ratio with increasing altitude and indicate higher CH₃CHO concentrations in the Northern Hemisphere — in general agreement with a model-derived average CH₃CHO distribution. Deviations of the observed CH₃CHO mixing ratios from the modelled mean distribution are correlated with similar deviations in the corresponding HCHO mixing ratios.     

Evidence of a 50-year increase in tropospheric ozone in Upper Bavaria

In a series of ozone-sonde soundings at the Hohenpeißenberg observatory, starting in 1967, the most striking features are increases of \sim2.2% per year in all tropospheric heights up to 8 km during the past 24 years. These facts have recently been published and discussed by several authors. In this paper, we present some evidence for the increase of tropospheric ozone concentrations during the past 50 years 1940–1990 in the territory of the northern edge of the Bavarian Alps, including the Hohenpeißenberg data. In December 1940 and August 1942, probably the first exact wet-chemical vertical soundings of ozone up to 9 km height were made by an aircraft in the region mentioned. These results were published in the earlier literature. We have converted the results of the flights on 4 days in December 1940 and on 6 days in August 1942 to modern units and have compared them with the Hohenpeißenberg ozone-sonde data of the December and August months. We also compared the data at the ground with the August results of Paris-Montsouris 1886-1898. Our results show an increase of ozone concentration at all tropospheric heights in Upper Bavaria during the past 50 years, compared with the Montsouris data in August during the past 105 years. In the recently published papers, the increases since 1967 were approximated linearly.Our results, extended to the past, show non-linear trends, with steeper increases since 1975-1979. Possible reasons for these findings are discussed. Quite recently (in case of the December months since 1986/87, the August months since 1990), the ozone mixing ratios at and above Hohenpeißenberg seem to have decreased.     

Structural phase transition in titanite,CaTiSiO5: A ramanspectroscopic study

The structural phase transition in titanite is correlated with a strong temperature dependence of Raman scattering cross sections and, to a somewhat lesser extent, with shifts of the phonon frequencies. Their quantitative temperature evolution in the low-symmetry phase (P2₁/a) is compatible with a nearly 2D Ising behaviour with β≈0.12 and T _c = 497 K. At temperatures above 860 K, the phonon signals agree with A 2/a symmetry but not in the temperature interval between 497 K and 860 K. In this temperature range new structural states give rise to additional phonon signals. A model based on mobile APBs between slabs of P2₁/a material, first proposed by van Heurck et al. (1991), is in qualitative agreement with our experimental observations.     

Hydrogen bonding in basic copper salts: a spectroscopic study of malachite,Cu2(OH)2CO3, and brochantite,Cu4(OH)6SO4

Infrared and Raman spectra of the basic copper salts malachite, Cu₂(OH)₂CO₃, and brochantite, Cu₄(OH)₆SO₄, as well as of deuterated and ¹³C substituted samples are presented and discussed in terms of group theory and the hydrogen bonds present. The main results are that (i) the hydrogen donor strengths of the OH^? ions are strongly increased due to the very great synergetic effect of the copper ions, (ii) the acceptor strengths of the H-bond acceptor groups (SO₄ ^2-, CO₃ ^2-, and OH^? ions) are significantly modified by the linkage and coordination of the acceptor atoms — this complicates true assignment of the OH bands observed to the two and six different OH^? ions present in malachite and brochantite, respectively -, and (iii) the Cu — O stretching modes at 430–590 cm^?1 and 420–520 cm^?1 for malachite and brochantite, respectively, exhibit strong, partially covalent Cu — O bonding.     

Bioaccumulation factors of chlorinated hydrocarbons between mussels and seawater

The bioaccumulation of PCB and DDT compounds by mussels, Mytilus spp., from ambient seawater was determined by measuring concentrations of these chlorinated hydrocarbons in both mussels and seawater at four sites on the Mediterranean coast of France and two sites in California. Bioaccumulation factors were found to vary over an order of magnitude. Ratios of the concentrations of PCB in mussels, consisting predominantly of pentachloro-and hexachlorobiphenyls, to concentrations in ambient seawater ranged between 69 000 and 690 000; the corresponding ratios of concentrations of p,p′-DDE or p,p′-DDT ranged from 40 000 to 690 000. Although mussels appear to be appropriate and convenient indicator organisms of local chlorinated hydrocarbon contamination levels, the factors contributing to this variance must be determined before mussels are widely used in global monitoring programmes.