Volume of Abstracts - Università degli Studi di Milano

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5 th Int. Workshop on Ice Caves (IWIC – V) Barzio (LC), Valsassina, Grigna and Milano, September 16 – 23, 2012 Volume of Abstracts TALUS & GORGE GLACIER PAST TO PRESENT - A HISTORICAL AND MICROCLIMATOLOGICAL RESEARCH IN THE NORTHEASTERN UNITED STATES Holmgren D. 1 & Pflitsch A. 1 1 Workgroup Cave & Subway Climatology, Department of Geography, Ruhr-University Bochum Universitätsstr. 150, 44801 Bochum, Germany On the North American continent, especially in the United States of America, natural and anthropogenic ice caves are scattered all over the country. Due to climate changes, most of these climate archives have been forgotten or don‟t exist anymore. Literary sources of the 19th and mid- 20th century identify the large number of ice caves known at that time of that territory [including Balch (1898); Halliday (1954)]. This presentation will outline a possible research potential in the underexplored North American ice caves and present the latest research results in Talus & Gorge Glaciers of the northern Appalachian Mountains. Alongside periodical fieldwork at the potential ice minimum, high-resolution temperature data loggers are measuring the air temperature in and near the talus since more than three years. The group of Talus & Gorge Glaciers is a type of ice cave with year-round ice bodies in hollow spaces. Regardless of the insolation conditions, like sun exposed hillsides or sun reduced gorges, ice can persist in these types of locations the whole year. The cave sizes of these ice caves are determined by the size of the talus accumulation; in most cases, the entire talus area is connected through little crevices and fissures and forms a complex interactive system. The occurrence of Talus & Gorge Glaciers is restricted to two regions in the USA. On the one hand they are found along the entire northeast coast and the other hand on the northwest coast, there exclusively in the state of Washington. In the context of the Talus & Gorge Glacier-Project in the Northeastern United States of America the development of the existence of ice caves from the 19th century up to now was determined. Mapping and exploration with the aid of local guides and older records form a map of the current situation in the Appalachian Mountains. Besides the mapping of all ice carrying debris accumulations in the USA, a microclimatological research of selected Talus & Gorge Glaciers, Ice Gulch, Cannon Cliff (both New Hampshire) and Mahoosuc Notch (Maine), was conducted. In the last years, ice level variability was observed through regular ice level measurements in these selected study areas. The observation of seasonal changes from the ice-buildup phase to the icedepletion phase over several years can serve as an outstanding climate indicator for short-term and long-term changes of the climate of the 29
5 th Int. Workshop on Ice Caves (IWIC – V) Barzio (LC), Valsassina, Grigna and Milano, September 16 – 23, 2012 Volume of Abstracts respective region. A comparison of the collected data with data of nearby reference stations results in important knowledge about the interaction of the climatological between the caves and the external environment. Yearround temperature measurements in the debris showed the strong influence of other climate elements. Typical climatic conditions for all seasons and for special seasonal events, such as a closed snow cover or a passing hurricane, were explored. The combination of ice level measurements with year-round temperature measurements yielded important information about favorable and unfavorable climatic conditions for the ice growth, which are also applicable to all other types of ice caves in the United States and all around the world. “CHIMNEY EFFECT” AND ITS INFLUENCE ON THE THERMAL CONDITIONS OF THE DOBŠINSKÁ ICE CAVE Korzystka M. 1 , Piasecki J. 1 , Sawiński T. 1 & Zelinka J. 2 1 University of Wroclaw, Institute of Geography and Regional Developnent, Dep. Of Climatology and Atmosphere Protection, ul. Kosiby 6/8, 51-621 Wrocław, Poland 2 Ministry of the Environment of the Slovak Republic, Slovak Caves Administration, Hodţova 11, 031 01 Liptovský Mikulaš, Slovak Republic (magdalena.korzystka@uni.wroc.pl, jacek.piasecki@uni.wroc.pl, tymoteusz.sawinski@uni.wroc.pl, zelinka@ssj.sk) The studies on the air exchange processes, conducted in the Dobšinská Ice Cave since 2002 have shown, that the cave ventilation is caused by the “chimney effect”. The driving force responsible for the course of the air exchange is differentiation between external air temperature (TEXT), air temperature inside ice-filled part of the cave (TCave) and air temperature inside its “chimney” part (TChimney), which probably is ice-free. Analysis of the course of these values allows to distinguish three main characteristic situations covering more than 95% of the year. In the first situation, which occurs in winter, TEXT < TCave < TChimney, in the second one, typical for spring and summer, TCave < TChimney < TEXT and in the third one, which occurs primarily in autumn, during slight cooling episodes, TCave < TEXT < TChimney. Observed relations between TEXT, TCave i TChimney as well as duration of characteristic situations mentioned above determine the temporal and spatial variability of air exchange in the cave and also affect the difference of energy balance between its individual parts. Direct effects of these interactions manifest themselves by seasonal and short-term variability of air temperature fluctuations observed in the cave, changes in spatial distribution of air temperature changes in thermal stratification of cave 30
Page 2 and 3: IWIC - V 5 th INTERNATIONAL WORKSHO
Page 4: President 5 th Int. Workshop on Ice
Page 7 and 8: 5 th Int. Workshop on Ice Caves (IW
Page 13 and 14: Dear Participants, we are very plea
Page 46: POSTER PRESENTATIONS
Page 61: 5 th Int. Workshop on Ice Caves (IW

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