Geologische und paragenetische Verhältnisse der Erzgänge des Jiblava-Jezdovicer Reviers

Ohne ZusammenfassungMit 18 Textabbildungen     

On the possible identification of ‘solid-state’ lines in T-Tauri stars

The possibility that the unidentified absorption lines observed in the spectrum of YY Orionis star S CrA can be attributed to the absorption features of irradiated amethyst is discussed.     

Environmental History of Lago di Tovel,Trento, Italy,Revealed by Sediment Cores and 3.5 kHz Seismic Mapping

Proxy data from a total of 30 sediment cores and information from a seismic survey show that the sedimentological and limnological history of Lago di Tovel (1178 m a.s.l.) has been significantly influenced by slope dynamics of its mountainous catchment. The lake represents a dead-ice lake with pro-glacial deposits at the base of its sedimentary record. A prominent lake level rise in 1597/1598 that increased maximum water depth from ∼20 to 39 m caused slope instabilities, leading to the deposition of mass-flow sediments with a maximum thickness of 2.5 m in the northern part of the lake and less than 50 cm in the southern part, resulting in a total volume of more than 113,000 m³. Consequently, a rough lake bottom morphology was produced, which led to distinct differences in sedimentation rates of 0.07 cm yr⁻¹ on sills and 0.18 cm yr⁻¹ within depressions. The age of the top of the mass-flow deposits was used to validate the ages of the younger, laminated sediments, which were dated by ²¹⁰Pb and ¹³⁷Cs. Lithological investigations showed that the sediments below the mass-flow deposits are also laminated and that they were not bioturbated. The long-term meromixis of Lago di Tovel is therefore mainly due to a combination of its topographic setting and the 5-month period of ice cover. Both prevent effective mixing of the lake by strong winds during spring and autumn. Distinct spatial differences in sediment distribution within the lake show that it is risky to interpret proxy data from only one coring site, even if the lake is very small. This is especially true in mountainous areas, where rock falls, mass movements, and slope instabilities of a significant size may have considerable effects on lakes.     

Callisto – A New Concept for Solar Radio Spectrometers

A new radio spectrometer, CALLISTO, is presented. It is a dual-channel frequency-agile receiver based on commercially available consumer electronics. Its major characteristic is the low price for hardware and software, and the short assembly time, both two or more orders of magnitude below existing spectrometers. The instrument is sensitive at the physical limit and extremely stable. The total bandwidth is 825 MHz, and the width of individual channel is 300 kHz. A total of 1000 measurements can be made per second. The spectrometer is well suited for solar low-frequency radio observations pertinent to space weather research. Five instruments of the type were constructed until now and put into operation at several sites, including Bleien (Zurich) and NRAO (USA). First results in the 45–870 MHz range are presented. Some of them were recorded in a preliminary setup during the time of high solar activity in October and November 2003.     

Comparison of Solar and Geomagnetic Activity Effects on the Northern Hemisphere Weather Changes

The changes of pressure and temperature fields in the winter lower troposphere observed in association with changes in solar and/or geomagnetic activity are compared. It is shown that the fact whether it was solar or geomagnetic activity was not so important as whether the levels of the two activities were high or low. The differences between the effects of solar/geomagnetic activity, however, are revealed, the pressure and temperature data being stratified according to the QBO phase. The relationship obtained are discussed from the viewpoint of mechanisms resting upon both the planetary wave propagation and the changes of atmospheric air currents in the global electric circuit.     

The Kyoto Protocol Emission Allocations: Windfall Surpluses for Russia and Ukraine

The emission targets adopted in the Kyoto Protocol¹ far exceed thelikely level of emissions from Russia and Ukraine. These countries could selltheir surplus if the Protocol is followedand industrialized countries establish an international emission tradingsystem. Critics have condemned the potentialsale and dubbed the surplus hot air because it does not represent anyreduction in emissions below the level thatwould have occurred anyway. Using the most recent, comprehensive regionalscenarios² for the emissions of carbon dioxide from the energysystem, we estimate that during the Protocol's2008–2012 budget period the surplus will range from 9 MtC (milliontons of carbon) to 900 MtC for Russia andfrom 3 MtC to 200 MtC for Ukraine. Even scenarios with high economic growthand carbon-intensive technologies donot exhaust the surplus before the budget period. In the central (middlecourse) scenario, the total carbon surplusexceeds 1000 MtC and is worth 22 to 170 billion U.S. dollars (4 to 34 billionU.S. dollars per year). This flow ofrevenues, which could exceed Russian earnings from natural gas exports($10 billion in 1997³), is comparable with the projectedtotal investmentsof the Russian energy system for 2008–2012. If directed towardslow-carbon infrastructure investments (e.g., gaspipelines), surplus transfers could reinforce and partially lock-indecarbonization of the world energy system.     

Locations of Footpoints of Transequatorial Interconnecting Loops

We discuss footpoints of loops seen by Yohkoh in soft X-rays that connect active regions across the equator (transequatorial interconnecting loops – TILs). While most TILs are rooted in moderately strong fields at peripheries of active regions, there are also cases when these loops are anchored in very weak or very strong fields, ranging from < 30 G to several hundred gauss. Some have their footpoints near sunspot penumbrae, creating `X-ray fountains' in a combination with active region loops. But TILs are never rooted in sunspots. The most likely explanation is that magnetic field lines leave spots almost vertically so that TILs rooted in them extend high into the corona and density in them is below the limit of visibility in X-rays. The fact that in force-free modeling some TILs are rooted in sunspots is most probably due to the difference between field-line connections in `vacuum' and in the highly conductive plasma on the Sun. Some TILs end before they reach active regions which sometimes may indicate the real situation, but mostly this `gap' is probably due to a temperature decrease near the loop footpoints which makes them invisible in X-rays. In that case the fact that these cool lowest parts of TILs are never found in TRACE or SOHO EIT images indicates that plasma density in TILs must be very low. Still, the total absence of any counterparts of X-ray TILs in TRACE and EIT images is puzzling and, therefore, other possible interpretations of the `gap' origin are also briefly mentioned.