Pufferungskurven der Gewässer in der Typologie

Ohne Zusammenfassung     

Cooling history and differentiation of a thick North Mountain Basalt flow (Nova Scotia,Canada)

A thick (<175 m) North Mountain Basalt flow at McKay Head, Nova Scotia (Canada) shows 25-cm-thick differentiated layers separated by 130 cm of basalt in its upper 34m. Upper layers (5 m below the lava top) are highly vesicular whereas lower ones are pegmatitic and contain a thin (2 cm) rhyolite band. The layering of the flow closely resemble that of some Hawaiian lava lakes. The eesicular basalts and mafic pegmatites are inferred to be liquid-rich segregations which drained into horizontal cracks that formed within a crystalline mush. The cracks resulted from a thermal contraction associated with cooling and shrinkage of the mush. Rhyolites were formed by in situ differentiation. Gas overpressures fractured the pegmatites and gas effervescence filter pressing forced silicarich residual liquid from pegmatite interstices into the fractures creating bands. Chemical differences between the pegmatitic layers and early formed, highly differentiated upper vesicular layers may reflect a role for volatiles in the differentiation process along with crystal fractionation.     

Elemental and organic carbon in atmospheric aerosols at downtown and suburban sites in Prague

Organic and elemental carbon (OC and EC) content in PM₁₀ was studied at two sites in Prague, which were located in a suburb and in the downtown. Similar overall average levels were found for both species and also for the PM₁₀ mass at the two sites (i.e., 5.5 and 4.8 μg/m³ for OC, 0.74 and 0.80 μg/m³ for EC, and 33 μg/m³ and 37 μg/m³ for the PM₁₀ mass at the suburb and downtown site, respectively), but substantial differences were observed between the two sites in some seasons and/or meteorological situations. Approximately three times higher values were found for OC in winter compared to summer, with a higher winter/summer ratio for the suburban site. The differences for EC were smaller, but still, compared to summer, more than two times higher EC levels were observed during autumn at the suburban site and 1.5 higher EC levels in winter and autumn at the downtown site. The lowest OC to EC ratios at the suburban site were 3.4, while they were around 1.3 for the downtown site. It was found that the origin of the air masses had a major impact on the observed PM₁₀ mass and OC levels, with largest concentrations noted for air masses recirculating over central Europe and arriving from southeastern Europe in winter. Trajectories coming from the west and northwest originating above the Atlantic Ocean and the Artic brought the cleanest air masses to the sites. For EC the largest difference between the two sites was observed for northwesterly winds during the non-heating season when the suburban site was upwind of Prague.     

Comparison of three types of laser optical disdrometers under natural rainfall conditions

ABSTRACT

Optical disdrometers can be used to estimate rainfall erosivity; however, the relative accuracy of different disdrometers is unclear. This study compared three types of optical laser-based disdrometers to quantify differences in measured rainfall characteristics and to develop correction factors for kinetic energy (KE). Two identical PWS100 (Campbell Scientific), one Laser Precipitation Monitor (Thies Clima) and a first-generation Parsivel (OTT) were collocated with a weighing rain gauge (OTT Pluvio²) at a site in Austria. All disdrometers underestimated total rainfall compared to the rain gauge with relative biases from 2% to 29%. Differences in drop size distribution and velocity resulted in different KE estimates. By applying a linear regression to the KE–intensity relationship of each disdrometer, a correction factor for KE between the disdrometers was developed. This factor ranged from 1.15 to 1.36 and allowed comparison of KE between different disdrometer types despite differences in measured drop size and velocity.     

Computation of the heat function connected with short-wave radiation fluxes

Summary A report is presented on the use of the method, suggested by H. and K. Lettau, for the purposes of computing short-wave radiation fluxes and the heat function, connected with them, in atmospheric models, used for short-range numerical weather forecasting.Dedicated to 90th Birthday of Professor Frantiek Fiala     

Daily variations of the characteristics of beating-typePc3 (Bpc3) pulsations

Summary The spectra of nearly 100 samples of Bpc3 pulsations were computed in the X and Y components of data from the Budkov Observatory. These spectra were used to study the daily variations of the fundamental characteristics of the pulsations, the frequency f ₀ and amplitude A ₀ of the main spectral peaks. The daily variation of the ellipticity of the polarization ellipses of oscillations in frequency f ₀ was also studied in the XY-plane.Part of these results was reported at the XVth General Assembly of the IUGG, Moscow, August 1971.     

Spectral analysis of geomagneticPc3 pulsations recorded at the observatories of Budkov and Belsk

Summary The numerical method of Fourier's spectral analysis is used to treat 29 pairs of samples of pc3 pulsations recorded at the observatories of Budkov (Czechoslovakia) and Belsk (Poland). The amplitude, frequency and phase characteristics of their spectra are compared. The polarization characteristics of the spectral frequency components of pulsations recorded at both observatories are compared in a quasi-stationary approximation of a plane oscillation.