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This is an Accepted Manuscript of an article published by Taylor & Francis in Norsk Geografisk Tidsskrift on 27 Oct 2017, available online: http://www.tandfonline.com/10.1080/00291951.2017.1391876. . Icy surfaces impose challenges for northern societies, wildlife and agriculture. However, there have been relatively few studies of the impacts of anoxic ground ice on non-agricultural plants. During the winter of 2009–2010, an extreme winter warming event led to thick ground-ice layer development in the world’s northernmost botanical garden in Tromsø, in subarctic Norway, due to much rain on warm days interspersed with cold dry days. After ice melt in late spring, the authors assessed plant mortality and tested whether certain growth forms, geographical origins, or terrain features were more vulnerable to stress. They found that mortality was negatively correlated with terrain slope, that cryptophytes were most vulnerable, and that good soil drainage improved all plants’ survival. Vegetation greenness (measured by the Normalized Difference Vegetation Index, NDVI) reached an unprecedented minimum in the summer of 2010 and remained low for two more years. The results suggest that more investigations of the impacts of ground ice are needed to understand better how alpine ecosystems might change with increasing climate change. In conclusion, the study revealed that botanical garden studies may be a valuable supplement to field studies, as plants of different origins could be studied under similar climatic conditions. anoxia, extreme event, NDVI, plant mortality, winter warming

The recently published digital version of the International Permafrost Association (IPA) Circum-Arctic Map of Permafrost and Ground Ice Conditions (the IPA map), together with ancillary data sets of the global land cover characteristics data base and the Global Land One-kilometer Base Elevation data base, are used to investigate the distribution of permafrost and ground ice in the Northern Hemisphere. Our study indicates that permafrost underlies approximately 22.79×106 km2 or 23.9% of the exposed land area of the Northern Hemisphere. Permafrost extends from 26°N in the Himalayas to 84°N in northern Greenland. Approximately 70% of the permafrost is distributed between 45 and 67°N. Generally, permafrost with high ice content (>20% by volume) and relatively thick overburden cover (>5 to 10 m) is found at high latitudes, representing approximately 8.57% of the total permafrost area, or 2.02% of the exposed land area of the Northern Hemisphere. Permafrost with low ice content (

Widespread warm permafrost with a high ice content is a key problem for the roadbed stability of the Qinghai–Tibet Railway. A new approach is proposed to alleviate the effect of global warming and engineering construction on permafrost by cooling the roadbed and positively protecting the permafrost. Measures for cooling the roadbed by adjusting solar radiation, conduction, and convection are studied and applied to prevent ground ice from thawing and to ensure roadbed stability in permafrost regions. The results of monitoring permafrost embankments at Beiluhe and along the Qinghai–Tibet Railway show that the measures adopted for cooling the roadbed are very effective in raising permafrost table and reducing the soil temperature.

The present‐day periglacial zones of the polar regions in both hemispheres have many features in common, caused by the peculiarities of climate, glaciological and geocryological processes, and the geomorphology of the periglacial regions. On the other hand, there exist essential differences in the general appearance of the periglacial zones in the Northern and Southern hemispheres, related mainly to particular features of continental glaciation. An analysis of the literature and of data from the author's field observations have allowed him to reach some conclusions as to the major features of the geocryology of the polar regions: the thickness, distribution, temperature, and cryogenic structure of the permafrost and of seasonally frozen materials and the ground ice and cryogenic relief of these areas. This, in turn, made it possible to identify a geocryological zonation of the polar regions and to advance a new concept as to the present‐day periglacial zone.

The author describes tight, asymmetrical minor folds in well‐bedded sands, loams and clays exposed by thermal abrasion of ice‐rich sediments on the west coast of Yamal and the north coast of Yugor Peninsula. The folds are commonly underlain by massive bodies of ground ice. The author postulates that the folds are the product of a southward flow of ice within an ice‐sheet sitting on the Kara Shelf, over unconsolidated sediments which were already frozen.

Positive forms of mesorelief in the north of Western Siberia, resulting from ice formation in frozen sediments, are analyzed. The role of cryogenic processes in their formation is evaluated. Three groups of frost mounds are distinguished, each resulting from different mechanisms. One category involves large, isolated mounds 20–30 m high with deep lakes around their bases and occasionally in their summits. A second type involves groups of mounds 5–10 m high forming elbow‐shaped or sickle‐shaped chains or ridges. And thirdly one encounters small mounds 3–4 m high, scattered in chaotic fashion over areas 1–2 km2 in area. Zonal and regional patterns in the distribution of all three types are discussed along with their morphological and cryological peculiarities.

A discussion of the various environmental impacts of the BAM and of the role of geographers in anticipating and preventing them. Intermontane basins offer relatively favorable areas for settlement, but lack of ventilation rules out the location of polluting industries. Avalanches, ground ice and snow drifting pose particular problems along the route, requiring special-purpose investigations and control measures. A mapping program is proposed to identify farming areas with the most favorable heat supply. A system of geographical field stations is needed to study environmental modification on the ground. Recommendations are made for optimal approaches to settling the BAM zone, distinguishing three categories of population groups: railroad workers, miners and lumbering personnel. Preservation of the indigenous hunting and reindeer economy is urged because of the importance of furs for exports and the use of reindeer as pack animals. Portions of the natural landscape are to be preserved for scientific purpose...

The article presents the results of investigations into the unique ground ice body located on the right bank of the Yenisey River, 120 km upstream from Igarka. It is overlain by flow till with an epi‐genetic type of cryogenic structure and a cryotexture involving coarse, reticulate, thick vertical streaks, with inclusions of lacustrine sediments and Holocene peat. The top of the underlying ice body is uneven and is in some places separated from the flow till by a layer of sand with lenses and bands of extremely bubble‐filled ice. The ice of the ice body contains almost no bubbles; it is characterized by a coarse‐grained structure, elongated crystals and the presence of dirt bands up to 12 cm thick. Isotope and chemical compositions of the ice in the ice body and of the vertical streaks in the flow till have been determined. Two explanations of the genesis of the ice body are advanced: formation of segregation ice underground or the burial of glacier ice.

The variability in ice-content profiles in the Arctic Coastal Plain is described and a computer model of coupled flow and ice segregation developed for the simulation of this system. The computer model demonstrated that the observed range in ice content could be a response to temporal and spatial variations in surface moisture. Further, the model produced an annual heave regime with summer compression and winter dilation in accord with empirical observation. Lastly, the model demonstrated that the active layer depth is significantly increased at wet sites.

Data on oxygen‐isotope composition of ice, together with the results of structural and textural analyses allow one to identify the genesis of ice bodies. Of all the types of underground ice in a particular region, ice of glacier origin has the lightest isotope composition. The paper presents the results of oxygen isotope analysis of samples taken from two cores extracted from different parts of a massive ground ice body, Ledyanaya Gora, located on the banks of the Yenisey River near the Arctic Circle. Comparison of these data with δ δ18 values from surface waters and ground ice in the Yenisey North and from present‐day glaciers on Severnaya Zemlya, indicates that the isotope composition of the ice of the Ledyanaya Gora differs from all these other types of H2 O from the area, with the greatest negative values; it is comparable only to the isotope composition of present winter precipitation on Severnaya Zemlya. It is concluded that the oxygen isotope method is very promising in terms of investigat...

The section of coast under consideration is developed on generally fine‐grained sediments with substantial ice contents and with polygonal ice wedges in some areas. Thermal abrasion is producing a range of typical coastal types. These include “cornice coasts,”; where a layer of surface peat has been left overhanging by the retreat of a body of massive ground ice, and “thermokarst slump”; coasts where the landward retreat of a slump‐scar in ice‐rich sediments and massive ground ice has outrun the zone of wave action and thermal abrasion which initiated it. Maximum rates of coastal retreat due to thermal abrasion in this area are 7–10 m per year; mean rates of erosion do not exceed 5–6 m per year.

New data are presented on investigations of the Ledyanaya Gora massive ground ice exposure made by the author in 1981–1983. They include information on the temperature, thickness and morphology of the ice body. The outlines of the ice body have been determined on the basis of geophysical investigations and instrumental surveys of the thermokarst slump‐scars. Data on the dynamics of the development of the exposure over the period 1972–1983 reveal a disastrously rapid destruction of the ice body. It is suggested that the exposure will survive for about another 10 years.

Rapid coastal erosion may be observed in many places in the Arctic as a result of thermal abrasion in ice‐rich unconsolidated sediments and especially in massive ground ice. In two instances, those of Semenovskiy and Vasil'yevskiy islands in the Laptev Sea, the result, documented in the literature, has been the disappearance of the islands. The authors analyze the results of various surveys and present their findings as to the pattern and rates of coastal erosion and lowering of the seabed (also due to thermal abrasion) on the sites of the former islands since their disappearance. (For comparison with the situation in the Beaufort Sea, discussion of the similar disappearance of St. Diomede Island in Laptev Strait and some ideas as to how this phenomenon relates to such “disappearing islands”; as “Sannikov Land”; see: William Barr, “Retreating coasts and disappearing islands in the Arctic,”; The Musk‐Ox No. 18, 1976, pp. 103–111.) (The translation is by William Barr of the University of Saskatchew...

(1853). LVI. On ground ice found in the beds of running streams. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science: Vol. 5, No. 33, pp. 340-345.

Starting from the premise that “shape is an important [spatial] property” (Bunge), the author analyzes the optimal shapes and dimensions of fragmented plots of arable land typical of Yakutia and other parts of the forest zone of the USSR. The optimal shape of an arable plot in a forest clearing is found to be an elongated piece of land of about 200–250 meters by 750–1500 meters and an area of 15 to 30 hectares. A program of land consolidation in the last decade has aimed at the elimination of excessively small plots and the expansion of mean plot size within the limitations of the Yakutian environment, where the presence of ground ice and thermokarst conditions produces a complex system of thaw depressions impeding the development of agriculture.

The chemical composition of beds of segregated ice in the pingos of northern Siberia is analyzed with particular reference to the origin of this type of ground ice and the heaving mechanism. A regu...

Stable, ice-cored frost mounds can form by differential ablation of seasonally developed massive ground ice. Although degradation frost mounds have no diagnostic mound morphology, these features can be identified by observing formative processes in the field and by examination of the mound core. Several field techniques were employed on massive ice-cored mounds which developed in a marsh near Slope Mountain, Alaska. Stratigraphic relationships within the mound core, ice petrofabrics, and ionic concentration patterns of ice crystals as they vary with core depth were correlated to the mound-forming processes, and indicate that these landforms are stable remnants of a sill-like massive ground ice plateau which has been differentially eroded by stream action. In addition, the core data and field observation can be used to infer the processes associated with massive ground-ice formation. It appears that a 1-m-thick, massive ice plateau develops in the marsh each winter due to the concordant injection and freez...