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Ultrathin Tropical Tropopause Clouds (UTTCs): I. Cloud morphology and occurrence (2003)

Thomas Peter Beiping Luo Martin Wirth Christoph Kiemle Harald Flentje Vladimir A. Yushkov Vyacheslav Khattatov Vladimir V. Rudakov Andreas Thomas Stephan Borrmann Guido Toci Piero Mazzinghi Jürgen Beuermann Cornelius Schiller Francesco Cairo Guido Di Donfrancesco Alberto Adriani C.-Michael Volk Johan Strom Kevin Noone Valentin Mitev Robert A. MacKenzie Kenneth S. Carslaw Thomas Trautmann Vincenzo Santacesaria Leopoldo Stefanutti

Subvisible cirrus clouds (SVCs) may contribute to dehydration close to the tropical tropopause. The higher and colder SVCs and the larger their ice crystals, the more likely they represent the last efficient point of contact of the gas phase with the ice phase and, hence, the last dehydrating step, before the air enters the stratosphere. The first simultaneous in situ and remote sensing measurements of SVCs were taken during the APE-THESEO campaign in the western Indian ocean in February/March 1999. The observed clouds, termed Ultrathin Tropical Tropopause Clouds (UTTCs), belong to the geometrically and optically thinnest large-scale clouds in the Earth's atmosphere. Individual UTTCs may exist for many hours as an only 200–300 m thick cloud layer just a few hundred meters below the tropical cold point tropopause, covering up to 105 km2. With temperatures as low as 181 K these clouds are prime representatives for defining the water mixing ratio of air entering the lower stratosphere.

Ultrathin Tropical Tropopause Clouds (UTTCs): II. Stabilization mechanisms (2003)

Thomas Peter Beiping Luo Martin Wirth Christoph Kiemle Harald Flentje Vladimir A. Yushkov Vyacheslav Khattatov Vladimir V. Rudakov Andreas Thomas Stephan Borrmann Guido Toci Piero Mazzinghi Jürgen Beuermann Cornelius Schiller Francesco Cairo Guido Di Donfrancesco Alberto Adriani C.-Michael Volk Johan Strom Kevin Noone Valentin Mitev Robert A. MacKenzie Kenneth S. Carslaw Thomas Trautmann Vincenzo Santacesaria Leopoldo Stefanutti

Mechanisms by which subvisible cirrus clouds (SVCs) might contribute to dehydration close to the tropical tropopause are not well understood. Recently Ultrathin Tropical Tropopause Clouds (UTTCs) with optical depths around 10−4 have been detected in the western Indian ocean. These clouds cover thousands of square kilometers as 200–300 m thick distinct and homogeneous layer just below the tropical tropopause. In their condensed phase UTTCs contain only 1–5% of the total water, and essentially no nitric acid. A new cloud stabilization mechanism is required to explain this small fraction of the condensed water content in the clouds and their small vertical thickness. This work suggests a mechanism, which forces the particles into a thin layer, based on upwelling of the air of some mm/s to balance the ice particles, supersaturation with respect to ice above and subsaturation below the UTTC. In situ measurements suggest that these requirements are fulfilled. The basic physical properties of this mechanism are explored by means of a single particle model. Comprehensive 1-D cloud simulations demonstrate this stabilization mechanism to be robust against rapid temperature fluctuations of +/−0.5 K. However, rapid warming (ΔT>2 K) leads to evaporation of the UTTC, while rapid cooling (ΔT<−2 K) leads to destabilization of the particles with the potential for significant dehydration below the cloud.

Check list of the Hungarian Salticidae with biogeographical notes (2003)

Tamas Szüts Csaba Szinetar Ferenc Samu Eva Szita

An updated check list of the Hungarian jumping spider fauna is presented. 70, species are recorded from Hungary so far. Four species are new to the Hungarian fauna: Hasarius adansoni, Neon valentulus, Sitticus caricis, Synageles subcingulatus. With 12 original drawings.

Fragmentation of exotic oxygen isotopes (2003)

Armin Leistenschneider Thomas Aumann Konstanze Boretzky Luiz Felipe Canto Brett Vern Carlson Dolores Cortina Ushasi Datta Pramanik Thomas W. Elze Hans Emling Hans Geissel Alexander Grünschloss Kerttuli Helariutta Margareta Hellström Mahir S. Hussein Stamenko Ilievski Jens-Volker Kratz Reinhard Kulessa Le Hong Khiem Edvard Lubkiewicz Gottfried Münzenberg Rudrayoti Palit Peter Reiter Christoph Scheidenberger Karl-Heinz Schmidt Haik Simon Klaus Sümmerer Eugeniusz Wajda Wladek Walús

Abrasion-ablation models and the empirical EPAX parametrization of projectile fragmentation are described. Their cross section predictions are compared to recent data of the fragmentation of secondary beams of neutron-rich, unstable 19,20,21O isotopes at beam energies near 600 MeV/nucleon as well as data for stable 17,18O beams.

Gorilla journal : nr. 27 / journal of Berggorilla- & Regenwald-Direkthilfe (2003)

Gorilla journal : nr. 26 / journal of Berggorilla- & Regenwald-Direkthilfe (2003)

Grzegorz A. Kleparski: First facts first (about Great Britain and the USA), Chełm, NKJO-Chełm-Publishers, 1999, pp. 167, ISBN 83-911683-0-1. (2003)

Dorota Skulimowsa-Grymuza

Mind, language and metaphor : Euroconference on consciousness and the imagination, Kerkrade (the Netherlands), april 20-24, 2002. (2003)

Pedro J. Chamizo Dominguez Carmen M. Bretones Callejas

The pitfalls of teaching grammar, lexis and Anglo-Saxon culture at a college level, ed. by Grzegorz A. Kleparski, Anna M. Pietrzykowska, Wydawn. Uniw. Rzeszowskiego, Rzeszów, 2001, pp. 106, ISBN 83-7338-035-3. (2003)

Jerzy Zabawa

Semantic interface in the entrenchment of loanwords and the estrangement of cognates (2003)

Clara Molina

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