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Centennial-scale mineral dust peaks in last glacial Greenland ice cores match the timing of lowest Greenland temperatures, yet little is known of equivalent changes in dust-emitting regions, limiting our understanding of dust−climate interaction. Here, we present the most detailed and precise age model for European loess dust deposits to date, based on 125 accelerator mass spectrometry 14C ages from Dunaszekcső, Hungary. The record shows that variations in glacial dust deposition variability on centennial–millennial timescales in east central Europe and Greenland were synchronous within uncertainty. We suggest that precipitation and atmospheric circulation changes were likely the major influences on European glacial dust activity and propose that European dust emissions were modulated by dominant phases of the North Atlantic Oscillation, which had a major influence on vegetation and local climate of European dust source regions.

Centennial-scale mineral dust peaks in last glacial Greenland ice cores match the timing of lowest Greenland temperatures, yet little is known of equivalent changes in dust-emitting regions, limiting our understanding of dust−climate interaction. Here, we present the most detailed and precise age model for European loess dust deposits to date, based on 125 accelerator mass spectrometry 14C ages from Dunaszekcső, Hungary. The record shows that variations in glacial dust deposition variability on centennial–millennial timescales in east central Europe and Greenland were synchronous within uncertainty. We suggest that precipitation and atmospheric circulation changes were likely the major influences on European glacial dust activity and propose that European dust emissions were modulated by dominant phases of the North Atlantic Oscillation, which had a major influence on vegetation and local climate of European dust source regions.

Centennial-scale mineral dust peaks in last glacial Greenland ice cores match the timing of lowest Greenland temperatures, yet little is known of equivalent changes in dust-emitting regions, limiting our understanding of dust−climate interaction. Here, we present the most detailed and precise age model for European loess dust deposits to date, based on 125 accelerator mass spectrometry 14C ages from Dunaszekcső, Hungary. The record shows that variations in glacial dust deposition variability on centennial–millennial timescales in east central Europe and Greenland were synchronous within uncertainty. We suggest that precipitation and atmospheric circulation changes were likely the major influences on European glacial dust activity and propose that European dust emissions were modulated by dominant phases of the North Atlantic Oscillation, which had a major influence on vegetation and local climate of European dust source regions.

Centennial-scale mineral dust peaks in last glacial Greenland ice cores match the timing of lowest Greenland temperatures, yet little is known of equivalent changes in dust-emitting regions, limiting our understanding of dust−climate interaction. Here, we present the most detailed and precise age model for European loess dust deposits to date, based on 125 accelerator mass spectrometry 14C ages from Dunaszekcső, Hungary. The record shows that variations in glacial dust deposition variability on centennial–millennial timescales in east central Europe and Greenland were synchronous within uncertainty. We suggest that precipitation and atmospheric circulation changes were likely the major influences on European glacial dust activity and propose that European dust emissions were modulated by dominant phases of the North Atlantic Oscillation, which had a major influence on vegetation and local climate of European dust source regions.

Centennial-scale mineral dust peaks in last glacial Greenland ice cores match the timing of lowest Greenland temperatures, yet little is known of equivalent changes in dust-emitting regions, limiting our understanding of dust−climate interaction. Here, we present the most detailed and precise age model for European loess dust deposits to date, based on 125 accelerator mass spectrometry 14C ages from Dunaszekcső, Hungary. The record shows that variations in glacial dust deposition variability on centennial–millennial timescales in east central Europe and Greenland were synchronous within uncertainty. We suggest that precipitation and atmospheric circulation changes were likely the major influences on European glacial dust activity and propose that European dust emissions were modulated by dominant phases of the North Atlantic Oscillation, which had a major influence on vegetation and local climate of European dust source regions.

Centennial-scale mineral dust peaks in last glacial Greenland ice cores match the timing of lowest Greenland temperatures, yet little is known of equivalent changes in dust-emitting regions, limiting our understanding of dust−climate interaction. Here, we present the most detailed and precise age model for European loess dust deposits to date, based on 125 accelerator mass spectrometry14C ages from Dunaszekcso, } Hungary. The record shows that variations in glacial dust deposition variability on centennial–millennial timescales in east central Europe and Greenland were synchronous within uncertainty. We suggest that precipitation and atmospheric circulation changes were likely the major influences on European glacial dust activity and propose that European dust emissions were modulated by dominant phases of the North Atlantic Oscillation, which had a major influence on vegetation and local climate of European dust source regions.

Dust in Greenland ice cores is used to reconstruct the activity of dust-emitting regions and atmospheric circulation. However, the source of dust material to Greenland over the last glacial period is the subject of considerable uncertainty. Here we use new clay mineral and < 10 mu m Sr-Nd isotopic data from a range of Northern Hemisphere loess deposits in possible source regions alongside existing isotopic data to show that these methods cannot discriminate between two competing hypothetical origins for Greenland dust: an East Asian and/or central European source. In contrast, Hf isotopes (< 10 mu m fraction) of loess samples show considerable differences between the potential source regions. We attribute this to a first-order clay mineralogy dependence of Hf isotopic signatures in the finest silt/clay fractions, due to absence of zircons. As zircons would also be absent in Greenland dust, this provides a new way to discriminate between hypotheses for Greenland dust sources.

Internet Service Provider platforms are typically heterogeneous and distributed environments with respect to both software and hardware. It is difficult to carry out coordinated, synchronized and traceable configuration and maintenance operations in these environments. As the income margins in the competitive ISP market are very narrow, service maintenance costs must be kept minimal. Functionally homogenizing the configuration and maintenance management of various network services and applications can help minimizing their associated costs. One possible approach is the adoption of CORBA, an industry-standard, distributed object framework. This would allow the creation of network transparent management interfaces and Web-based configuration graphical user interfaces. From the configuration and maintenance point of view existing applications and services should be either encapsulated into CORBA objects using specially designed CORBA wrappers or they should be accessed using a CORBA gateway. New applications could be written with native CORBA interface for configuration and maintenance or with similar CORBA wrappers. This thesis focuses on the requirement analysis of a configuration management system using CORBA., Internetpalveluntarjoajien alustat ovat tyypillisesti hajautettuja ja heterogeenisiä järjestelmiä sekä ohjelmiston että laitteiston osalta. Tällaisissa ympäristöissä on vaikea suorittaa koordinoituja, synkronoituja ja helposti valvottavia konfigurointi- ja ylläpitotoimenpiteitä. Koska kiristynyt kilpailu palveluntarjoajamarkkinoilla on pienentänyt katetta, on palvelujen ylläpitokustannukset ehdottomasti minimoitava. Verkkopalvelujen sekä sovellusten konfiguraation ja ylläpidon hallinnan yhtenäistäminen on eräs keino kustannusten minimointiin. Eräs lähestymistapa ongelman ratkaisemiseksi on CORBA:n käyttöönotto palvelujen hallinnassa. CORBA on teollisuusstandardin aseman saavuttanut hajautettu oliokehysympäristö. CORBA:n käyttö mahdollistaisi läpinäkyvien hallintarajapintojen ja graafisten konfigurointikäyttöliittymien kehityksen. Konfiguraation hallinnan kannalta jo olemassa olevia palveluita varten olisi kehitettävä varta vasten suunniteltu CORBA-adapteri tai palvelut pitäisi hallinnoida CORBA-yhdyskäytävän kautta. Uudet palvelut tulisi joko laatia CORBA-pohjaisilla hallintorajapinnoilla varustettuina tai vastaavasti niitä tulisi mukauttaa CORBA-adaptereilla. Tässä työssä keskitytään CORBA-pohjaisen konfiguraatiohallintajärjestelmän vaatimusanalyysiin.