Numerical Simulation of Wind

Topographic Models and Numerical Conditions In order to ascertain the topographic screening effect of the dead-ice zone on valley winds, three-dimensional numerical simulation of airflow was carried out (Fig. 8) 18 . Topographic figures of actual size for the water surfaces and surrounding moraines of Tsho Rolpa and Imja (Fig. 1A and B) were built up in the calculation domain of x x y x z 7,000m x 2,000m x 400m. By referring to 1 50,000 scale topographic maps of 1996 and 1997 and data of...

References

1 Yamada, T. (2000) Glacier lake outburst floods in Nepal. Seppyo, 62, 137-147. 2 Sakai, A., Chikita, K. and Yamada, T. (2000) Expansion of a moraine-dammed glacial lake ,Tsho Rolpa, in Rolwaling Himal, Nepal Himalaya. Limnology and Oceanography, 45, 1401-1408. 3 Yamada, T. (1993) Glacier lakes and their outburst floods in the Nepal Himalaya. Report of Water and Energy Commission Secretariat (WECS), Kathmandu, Nepal, 37 pp. 4 Yamada, T. (2001) Meteorological-hydrological environment and...

Conclusion Of Soil Temperature

It is possible that the ability of fungi to adapt to low and changing water activities, whether due to frigid temperatures or high salinities, is crucial for their successful survival in some of the harshest extreme environments on Earth. Since the majority of microbiological studies in the polar regions are oriented on the investigation of psychrophilic bacteria, the occurrence of fungi, one of the ecologically most successful eukaryotic lineages, has received little attention so far. However,...

Theory of Soil Physics

The earth system has various interactions between its various spheres (lithosphere, cryosphere, atmosphere, ocean). These interactions occur at various temporal and spatial scales. Depending on the time scale one is interested in certain processes are so slow that they seem not even to exist and hence are negligible at this scale (Fig. 1). For instance, at the typical forecast range of NWPMs (up to 5 or 10 days) the spatial distribution of permafrost does not change, but the active layer depth...

Pipelines Buried Conduits and Ducts

Thermal disturbances from buried pipelines can cause significant problems (e.g. Burgess and Smith, 2003 Huang et al., 2004 Palmer and Williams, 2003 Tart and Ferrell, 2002). Chilled pipelines may induce frost heave due to ice segregation and ice lens growth (Konrad, 1994), whereas warm pipelines induce additional thaw around the pipe, which results in thaw consolidation and settlement. In addition, deformation processes on steep slopes, such as creep or solifluction, may cause structural damage...

Distribution of Permafrost in Canada

Permafrost is defined on the basis of temperature as ground (i.e. soil and or rock) that remains at or below 0 C for at least two consecutive years 13 . Permafrost is most commonly associated with various types of ice (ice-bonded permafrost), but if there is insufficient interstitial water the permafrost is dry (dry permafrost). Permafrost distribution in Canada shows a latitudinal zonation (Figure 1). In the south it is discontinuous, while in the north it is continuous. Two zones are...

Info

Comparison of soil temperature as simulated with HTSVS and observed at Yakutsk, Siberia. The time step used in (a) is three times smaller than that used in (b). Observation data from Levine (2007 pers. communication). Table 2. Typical mean values and standard deviations (in brackets) of soil characteristics. The symbols ks, ns, b, ys, ps stand for the hydraulic conductivity at saturation, porosity, soil-pore distribution index, and density of the dry soil material. References are (a)...

Patterned Ground and Active Layer Phenomena

There has not been much focus on the incidence of patterned ground and active layer phenomena on Disko Island. Ice-wedge polygons associated with thermal contracting cracking are not a widespread landform, but do occur in some areas such as at the northern end of Blresedalen (Figure 7). However, various forms of sorted and unsorted circles (Figure 8) and stripes (Figure 9) are very common and occur from sea-level to high altitudes. Movement in the active layer is also evident in areas with high...

Empirical Data

This chapter presents the empirical field data. Ready to use data (maps) can be found in Figs.1 and 3. Readers wishing to modify details are referred to the following detailed sections. Other readers can proceed directly to the maps and from that to the discussion in sections An important point is, that extending the data from CLIMAP the Tibet Plateau was during the LGP and possibly during older neogene glacials covered by a large inland-ice that extended 2.4 Mio km2. Paragraph two presents...

Conclusion

Permafrost bacteria represent a unique opportunity to study the origin and modes of dissemination of drug-resistance determinants in environmental bacterial populations. In this work, we, for the first time, isolated strains resistant to different antibiotics from permafrost bacterial populations that originated from Arctic and Antarctic sediments of different ages and genesis. It turned out that many of the antibiotic-resistant bacteria in the permafrost collection contained genes highly...

Measurements of Ground Temperature Lapse Rates at 50Cm Depth and Pit Surveys

The diurnal variation in ground temperature is negligibly small at depths below 40 to 50 cm. The lapse rate of the ground temperature at 50-cm depth (GT50) during summer in the seasonal-frost zone is close to that of the air temperature, because the GT50 is principally controlled by ground heat flux for some days (Fig. 4). However, the GT50 lapse rate in the permafrost zone during summer is much larger than that of air temperature, because the GT50 is controlled by not only ground heat flux but...

Uncertainty in Permafrost Modeling

The atmospheric science community spend huge efforts on investigating uncertainty in modeling the soil conditions in atmospheric models because errors in simulated soil states and fluxes may propagate into errors in atmospheric state variables and fluxes. The following sources of error have been identified Discretization, vertical and temporal resolution Initial and boundary condition Subgrid-scale heteorgeneity Assumptions and or parameterization concepts Uncertainty in soil physical...

Introduction

This chapter describes recent cryogenic forms of North-western Canada and relict forms of the Carpathian Basin to draw comparison between them. The objectives of this chapter are to document them, discuss their paleoenvironmental significance from a process viewpoint and to demonstrate their application for reconstructing the past periglacial history of the central European area. The theory of climatic geomorphology 4 and uniformitarianism 32 give us possibility to compare different time and...

Periglacial Weathering Processes

In many of the major valleys large blocks of rocks have been detached from the walls and are now occupying the valley slopes (Pedersen et al., 2001). In Kuannersuit Kuussuat (Kuannersuit Valley), there are no obvious signs of glacial abrasion on the relocated blocks, although they have been eroded by fluvial processes. This leads to the preliminary interpretation that the large detachments are a paraglacial phenomenon related to pressure-release on valley walls during the deglaciation of the...

Pile Foundations and Grouting

Pile foundations in permafrost mobilise resistance mainly by side friction rather than end bearing and therefore only side friction is to be accounted for in a design. In consequence, load transfer between the pile and the surrounding ground is therefore crucial and thermal disturbances, as described above, must be minimised. Sego and Biggar (1990) present four ways that grout will cure adequately at sub-zero ground temperatures 1) grout temperature may be artificially maintained above 0 C...

The Panama Seaway

S18O records of planktonic foraminifera (Tiedemann et al. 1994 Shackleton et al. 1988 Morley and Dworetzky 1991) have shown that large northern Hemisphere glaciations began about 2.75 MaB.P. from 1 MaB.P. onwards, its intensity (ice volume) and the length of its glacial phases approximately doubled (Fig.4b). Sometimes the closure of the Panamanian seaway and the resulting impact on North Atlantic deep water formation are mentioned in connection with the onset of the ice ages (Haug and Tiedemann...

Diversity of Fungi

The main taxa of fungi isolated from the high Arctic glaciers include melanized fungi that were mainly represented by the oligotrophic genus Cladosporium, taxonomically and phylogenetically closely related to the black yeast-like halotolerant genus Aureobasidium. Among melanized fungi the genera Alternaria and Phoma occured with low frequencies. Filamentous fungi, isolated with high frequency were represented by the cosmopolitan anamorphic genera Aspergillus and Penicillium, together with the...

Construction Challenges in Mountain Environments

Using permafrost as a foundation and accounting for permafrost in the environment that may cause slope instability hazards are only part of the challenge when constructing in mountainous environments. There are many additional ones that need timely planning. The remote location of the construction is demanding on the logistics. Electricity and water may not be available and may have to be supplied to the site. Accommodation and food has to be planned for the site, and the effects of altitude on...

Simulating Frozen Ground

Since the cross-effects are very small under most conditions and since volumetric heat capacity and thermal conductivity of the substrate influence each other only marginally, decoupled equations to describe the energy- and water-transport within the soil are commonly used (e.g., Deardorff 1978, McCumber and Pielke 1981, Gro 1988, Dickinson et al. 1993, Schl nzen 1994, Jacobson and Heise 1982, Eppel et al. 1995, Chen and Dudhia 2002, Dai et al. 2003). However, this decoupling is realized in...

Ground Thermal Control

Changes in the ground thermal regime are the major cause of problems with permafrost infrastructure. Efforts should therefore be made to limit the changes in the ground temperatures and in particular to prevent phase changes in the ground. By moving the active layer into soils that are non-frost susceptible, frost heave and thaw settlements can also be avoided. Figure 18 shows various sketches of suitable foundations in permafrost environments. The various methods are described below. Special...

Mountain Infrastructure and Alpine Permafrost

Typical infrastructure in mountainous environments is listed above. Some structures may have to be tied back with anchors reaching into permafrost. Further hazards to infrastructure, settlements or reservoirs are evoked by slopes located in permafrost that may trigger mass movements during rainfall infiltration or thawing of snow or ice. Due to the heterogeneity of the mountain environment, with the lower permafrost boundary changing significantly within short distances, structures are often...

Cryogenic Features and Their Implication For Palaeoclimate

Central Yukon has a sub-Arctic continental climate with long, bitterly cold winters, short mild summers, low relative humidity, and low to moderate precipitation (Table 3). Intrusions of mild air from the Pacific Ocean moderate the climate of the region from the Arctic climate that characterizes northern Yukon 77 . The Dawson Range shares this climate modified by higher elevations. However, higher elevations do not necessarily experience colder temperatures throughout the year. Air temperature...

Rock Glaciers

Nearly 1700 individual rock glaciers have been identified on Disko Island (Humlum, 1988a). The earliest descriptions of rock glaciers were made by Steenstrup (1883, 1901) and Hammer and Steenstrup (1893), who referred to rock glaciers as 'dead glaciers'. Many rock glaciers have been named by the Inuit, for instance the large Ujaragsuit rock glacier south of Qullissat on the northeast coast. Both glacier-derived rock glaciers (Figure 2) and talus-derived rock glaciers (Figure 3) are abundant all...

Laboratory Testing

Laboratory testing is an essential addition to field investigations. Due to lack of finances, poor planning and absence of specific permafrost knowledge this is hardly ever carried out for mountain permafrost projects, in particular in the Alps, except for simple soil classifications. It is, however, crucial when determining geothermal and geotechnical soil properties because these parameters can be measured in a controlled environment and extreme boundary conditions can be applied. It is...

Isostatic Impact of the Tibetan Inland

A glacio-isostatic drop of the plateau of about 600-700 m must have occurred (Kuhle, M. & Kuhle S. 1997 p.124-129). (Density difference of ice versus material of the earth's mantle (g 1 2.4 at an ice thickness of 1000 to 2700 m 417 to 1125 m glacio-isostatic drop). Since deglaciation occurred about 9000 years ago, remnants of glacio-isostatic uplift with downward tendency should still be observable, as in Central Scandinavia (Morner 1978) or the Pleistocene glaciation of North America...

The Lapse Rate Change of the GT50 In 1973 and 2004

Figure 5a shows the revised GT50 for locations on southern-aspect slopes in 1973 versus the altitudes of the revised GT50. The data were derived from Fujii and Higuchi (1976). In 1973, while the lapse rate below 5200-5300 m was close to that of air temperature (0.5 C 100 m), the lapse rate above 5200-5300 m became much larger than that of air temperature (3.4 C 100 m). Thus, the permafrost lower limit of the south-facing slope was estimated as 5200-5300 m in 1973. In 2004 (Fig. 5b), while the...

Fungi in Polar Regions

Cold polar regions are extreme environments, in which the majority of studies have been oriented towards psychrotolerant psychrophilic bacteria, while the occurrence and diversity of psychrotolerant psychrophilic fungi remained largely unknown. So far, fungi have been reported primarily in connection with sub-Arctic vegetation and soil in polar regions. Mainly basidiomycetous yeasts were isolated from berries, flowers, vegetation of the littoral zone, soils, forest trees, grasses Babjeva and...

Geotechnical Properties of Alpine Permafrost

Arenson et al. (2007) present an overview of geotechnical properties of frozen soils and the many factors that have an influence on the mechanical response of permafrost soils. As high ice contents with excess ice and high air contents are often found in soils in mountainous environments, this section focuses on soils with these properties. Andersland and Ladanyi (2004) or Esch (2004) present thorough overviews for the remainder of the spectrum of frozen soils. An additional overview on most...

Permafrost Studies in Nepal Himalayas

The mountain permafrost lower limit has been studied in the Khumbu Himal, the Nepal Himalayas, since 1973 (Fujii and Higuchi, 1976 Jakob, 1992 Barsch and Jakob, 1993). Fujii and Higuchi (1976) measured ground temperatures and found that the permafrost lower limit on slopes with a northern aspect was about 4900-5000 m in 1973. Barsch and Jakob (1993) conducted seismic refraction soundings and estimated that the lower limit on slopes with a southern aspect was 5400-5500 m in 1991. Fukui et al....

Study of Antibiotic Resistance Spectrum of Permafrost Strains

About half of the antibiotic resistant strains obtained after initial selection, were chosen for further work. Among them we identified 53 strains of Gram-positive and 30 strains of Gram-negative bacteria. For each of these strains we determined the spectrum of resistance to all antibiotics used previously (Km, Gm, Sm, Tc, Cm). This analysis revealed not only strains resistant to a single antibiotic, but also strains resistant to two and three different antibiotics. The frequency of strains...

Glacial Ice as Potential Ecological Niches for Xerotolerant Halotolerant Fungi

Due to the adaptive fungal behaviour at low aw, we have assumed that coastal Arctic environments, in particular diverse type of ice, could represent a potential ecological habitat for xerotolerant halotolerant fungi. High concentrations of NaCl create both ionic and osmotic stress, while high concentrations of sugars and drought cause osmotic stress. There is great similarity between osmotic stress and matric water stress since in both cases the water activity is low. As water becomes ice it is...

Permafrost Strains

It is known that bacteria of various systematic groups are characterized by different intrinsic antibiotic resistance moreover they may be cross-resistant to several classes of antimicrobial agents Piddock, 2006 . Bacteria may also acquire resistance via the horizontal transfer of specific genes from other organisms Davies, 1994 Tenover, 2006 . To study the mechanisms of antibiotic resistance in our collection of multidrug resistant permafrost bacteria we determined the localization of the...

Kazuhisa A Chikita

Department of Natural History Sciences, Faculty of Science, Hokkaido University, Many supraglacial lakes have appeared and expanded in the Himalayas since the 1950s by glacial retreat, probably due to global warming after the Little Ice Age. Some of these lakes have produced glacial lake outburst flood (GLOF) events since the 1960s, which have occurred, on average, once every three years somewhere in the Himalayas. The three glacial lakes, Tsho Rolpa (water level 4,580m a.s.l.) and Imja (5,009m...

Ice Thickness Lowest Position of Ice Margins around the Tibetan Plateau and the Depression of the Equilibrium Line

Dhaulagiri- and Annapurna Himalaya Determined from the position of 46 glaciers, the present ELA on the southern edge of Tibet, south and north of the Dhaulagiri- and Annapurna Himalaya (Fig.1, No.26), lies at about 5550 m asl. It was calculated following the established methods of von Hofer (1879), Louis (1955) and Lichtenecker (1938), outlined also in Kuhle 1982a, 1983, 1988a. In particular, the ELA north of the main crest of the Himalaya is at 5620 m and south of it at 5490 m. Moraines...

R

Cryptococcus liquefaciens, the yeast species most frequently isolated from subglacial samples Among the remaining basidiomycetous yeast species detected in lower numbers, Cr. albidus was the most abundant (up to 5 x 105 CFU L-1) Butinar et al., 2007 . T. mucoides is considered an opportunistic pathogenic species Kurtzman and Fell, 1998 and it was unexpectedly obtained in high counts (8 x 105 CFU L-1), though only from one glacier Butinar et al., 2007 . Our group isolated this species...

Nicole Molders and Gerhard Kramm

'Department of Atmospheric Sciences, Geophysical Institute, 2University of Alaska Fairbanks, Geophysical Institute, University of Alaska Fairbanks, College of Natural Science and Mathematics, This chapter briefly reviews current state-of-the-art in modeling permafrost in numerical weather prediction models (NWPMs), chemistry transport models (CTMs) and in general circulation models (GCMs) and earth system models (ESMs) for projecting the global climate. Pros and cons of various methods are...

Dtv avDw ns nL

Here g, a, v, Dw, pd, and R are gravity acceleration, a torsion factor that considers curvatures in the soil material due to roots (Sasamori 1970, Zdunkowski et al. 1975, Sievers et al. 1983, Kramm et al. 1996), a correction factor that is typically close to 1, the molecular diffusion coefficient of water vapor in moist air, and the density and gas constant for dry air, respectively. In Eq. (1), the first term on the right side represents soil-temperature changes by divergence of soil-heat...

Soil Temparature References

Observations of open system pingos in a marsh environment, Mellemfjord, Disko, Central West Greenland. Danish Journal of Geography, 95, 42-48. Christiansen, H.H. (1997). Observations of open system pingos in a marsh environment, Mellemfjord, Disko, Central West Greenland a reply to Gurney and Worsley. Danish Journal of Geography, 97, 157-159. Christiansen, H.H., Sigsgaard, C., Humlum, O., Rasch, M. and Hansen, B.U. (2008). Permafrost and periglacial geomorphology at...

Phenomena Related to Permafrost Degradation

Diagrams Landslide

A large earthquake (magnitude 7.3 according to the U.S. Geological Survey) struck the Russian Altai on 27 September 2003. This earthquake was the largest in the region since the earthquake of 20 December 1761, which is thought to have had a magnitude of approximately 7.7. A large landslide occurred on the north-facing slope (2000-2200 m ASL) of the Taldura valley after the 2003 earthquake (Fig. 12), forming a landslide scar along the boundary between the larch forest and the steppes. The wide,...

Cryogenic Features in Canada

Polygonal Network Permafrost

The study of paleosols in northwestern Canada (Figure 1) in central Yukon (around Dawson City), in the Old Crow Basin reviled numerous cryogenic features, which developed in the past. On the other hand those cryogenic features studied in the Mackenzie River Delta areas are represent active processes. Cryogenic features were observed on a pre-Reid glaciofluvial terrace near Wounded Moose Dome about 70 km southeast of Dawson City and near the limit of Pleistocene glaciations in central Yukon 56 ....

InSitu Site Investigation Geomorphology Geology

The analysis of the geomorphological features at a given site provides a preliminary diagnosis of whether permafrost is present or not. In addition to the analysis of topographical maps and aerial photographs, in-situ site investigations are carried out to identify potential permafrost-related features, prior to more complicated and costly geophysical and geotechnical investigations. The use and relevance of geomorphological analyses is unfortunately often underestimated, although the method is...

Study Sites and Observations

Tsho Rolpa (water level, 4,580m a.s.l. 27 51'N, 86 29'E) and Imja (5,009m a.s.l. 27 54'N, 86 55 E) in the Nepal Himalayas and Lugge (4,539 m a.s.l. 28 5'N, 90 18'E) in the Bhutan Himalayas (Fig. 1) commonly contact both side moraines and the cliff-shaped glacial terminus at uplake (Fig. 2A). Imja and Lugge abut on the dead-ice zone at downlake, which is 20 to 30m higher than the lake level, but Tsho Rolpa touches the end moraine near the lake level (Fig. 2B). The histories of the lake expansion...

The Earliest LGP

Fig.3 shows the reconstruction of the maximum glaciation in Tibet, with an area of about 2.4 million km2. In the central part it formed a compact inland ice sheet with outflows that descended through the surrounding mountains and terminated at the steep edges of the high plateau. To err on the safe side, the 50-70 m high, glaciofluvial gravel terraces east of 84 -85 E (Fig.1, Nos.10, 11), which lie there on a valley floor at 3800-3900 m asl, are classified as High Glacial deposits (Kuhle 1988c...

Relict Cryogenic Forms in Hungary

Thermal-contraction-crack polygons are the most widespread, most visible, and most characteristic feature of permafrost terrain. Thermal-contraction cracks can be filled with ice, mineral soils (sand, loess, etc.), or a combination of both 13 . In cold aeolian environments, the progressive primary infilling of thermal contraction cracks with sand forms distinctive sedimentary structures known as sand wedges 49 . Wedge-shaped bodies of sand can also form by secondary infilling of voids resulting...

Numerical Simulation of Lake Currents Preparation

In order to quantitatively certify the hydrodynamic system in Tsho Rolpa (Fig. 6), lake currents were three-dimensionally simulated by making a three-dimensional figure of the Tsho Rolpa lake basin in the calculation domain (Fig. 11). The lake basin of actual size was made up by referring to the bathymetric map of 1992 (Fig. 1) 9 . The new version of the CFD program for the airflow simulation, PHOENICS 2006, was used for the lake current simulation. Considering spatial distributions of ice mass...

Bacterial Strains

As the first step to identification of the antibiotic resistance determinants of ancient bacteria, we tested permafrost strains from our collection for the presence of known genes encoding for streptomycin resistance. Seven strains resistant to different antibiotics (Table 2) isolated from different locations of Siberian and Antarctic permafrost were chosen for comparative analysis of antibiotic resistance determinants (Table 7). Four of these strains contained plasmids and (or) transposons...

Permafrost Degradation Between 1973 and 2004

The lapse rate change in 2004 at GT50 indicated that the permafrost lower limit lies between 5400 and 5500 m on south-facing slopes of the Khumbu Himal. The frozen layer was found below 45 cm at P1 located at 5540 m. Because ground freezing had already started by 20-21 October, this frozen layer had likely survived from the preceding summer and could be considered permafrost. Judging from the above results, the permafrost lower limit on slopes with a southern aspect in the Khumbu Himal lay...

Results And Discussion

Table 1 shows a list of the surge-type glaciers on Disko Island classified in this study. Eight glaciers have experienced surge events since 1953, three glaciers advanced between 1931 and 1953, which are likely to have been surge events, and 64 glaciers are inferred as surge-type glaciers due to one or more significant surge characteristics. Out of the 247 glaciers larger than 1 km2, 30 are classified as surge-type glaciers. Of the previous 24 glaciers classified as surge-type, six (glaciers...

Description Of Sites in Hungary

Aeolian Sandy Soil

Large V-shaped features are to be found in a gravel pit (47 35'N, 19 13'E 255 m a.s.l.) near Mogyorod (15 km north-east of Budapest) in the northern part of the Godollo Hills (Figure 8). The geological section at this site is composed of two very different deposits 12, 65 . The lower deposit is an Upper Pliocene alluvial fan of Palaeo-Danube origin overlain by aeolian sandy deposits. A thick, red paleosols developed on the lower deposit. The color is yellowish red (5YR 5 8) and the thickness of...

References In Soil Temperature

Andersland, O.B. and Ladanyi, B., 2004. An introduction to frozen ground engineering. John Wiley & Sons, Inc., Hoboken, New Jersey, 363 pp. Anderson, D.M. and Tice, A.R., 1972. Predicting unfrozen water content in frozen soils from surface area measurements. No. 393, Highway Research Record. Arenson, L.U., 2002. Unstable alpine permafrost a potentially important natural hazard -variations of geotechnical behaviour with time and temperature. Doctoral Thesis No. 14801 Thesis, Swiss Federal...