scholarly journals Permafrost Distribution in Peatlands of West-Central Canada During the Holocene Warm Period 6000 Years BP

2007 ◽  
Vol 49 (1) ◽  
pp. 45-54 ◽  
Author(s):  
Stephen C. Zoltai
Keyword(s):  
Land Surface ◽  
Floristic Composition ◽  
Climatic Conditions ◽  
Warm Period ◽  
Tree Cover ◽  
The Arctic ◽  
Mean Annual Temperature ◽  
The North ◽  
West Central ◽  
Central Canada

ABSTRACTThe extent and distribution of permafrost in peatlands 6000 years ago was investigated in the present discontinuous and continuous permafrost zones of west-central Canada. Permafrost peatlands were cored at 161 locations and the floristic composition of the peat was determined from macrofossil analysis. The reconstructed paleoenvironments were used to indicate the presence or absence of permafrost at the time of peat formation. Chronological control was provided by radiocarbon dating of substantial changes in the peat sequences and by dates of basal peat deposits. Peatland formation began after glacial ice disappeared from the land surface of west-central Canada. Macrofossils indicate that most peatlands were fens without permafrost at 6 ka, except in the far north. Permafrost was already present in many areas of the Arctic, and peat accumulation occurred under permafrost conditions. In the southern area, permafrost development in peatlands began about 4 ka as the middle Holocene warm period came to a close. Permafrost development in the fens was associated with the development of a Sphagnum-dominated surface on the fens, caused by the onset of a cooler and moister climate. The insulation provided by the surface peat layer and by the associated tree cover initiated permafrost development in small lenses that coalesced into large permafrost bodies according to the prevailing climatic conditions. At the target date, 6 ka, permafrost was present in some peatlands, but the distribution zones shifted 300 to 500 km to the north, relative to the present zonation. It is estimated that this corresponds to a mean annual temperature that was about 5°C warmer than at present.

Sustainable Development of the Arctic

2019 ◽  
pp. 396-415
Author(s):  
Liudmila Lapochkina ◽  
Elena Vetrova
Keyword(s):  
Sustainable Development ◽  
Natural Resources ◽  
Negative Impact ◽  
Methodological Approach ◽  
Climatic Conditions ◽  
The Arctic ◽  
International Treaties ◽  
The Sustainable Development ◽  
Criteria And Indicators ◽  
The North

Circumpolar territories and the regions related to the Arctic are those rich with natural resources. They have a high potential for the development of mining and extractive industries. The abundance with resources makes the North increasingly attractive for investments. However, circumpolar territories are characterized by peculiar socio-economic, natural, and climatic conditions which taken together frequently pose a negative impact on people and hinder the exploration opportunities of the Arctic resources. In global, regional, and sub-regional levels, the development of the Arctic is heavily regulated by multilateral international treaties. However, the issues of monitoring and assessment of the sustainable development of the Arctic remain open, which stems from the absence of agreed criteria and indicators for assessing sustainability in the context of national, regional, and scientific approaches. It necessitates the development of a specific methodological approach to the establishment of a system to monitor and assess the sustainable development of the Arctic.

scholarly journals Simulating the mid-Pliocene Warm Period with the CCSM4 model

2013 ◽  
Vol 6 (2) ◽  
pp. 549-561 ◽  
Author(s):  
N. A. Rosenbloom ◽  
B. L. Otto-Bliesner ◽  
E. C. Brady ◽  
P. J. Lawrence
Keyword(s):  
Heat Transport ◽  
Southern Oscillation ◽  
Warm Period ◽  
Meridional Overturning Circulation ◽  
Sea Surface ◽  
Mean Annual Temperature ◽  
Sea Ice Extent ◽  
The North ◽  
Intercomparison Project ◽  
Global Precipitation

Abstract. This paper describes the experimental design and model results from a 500 yr fully coupled Community Climate System, version 4, simulation of the mid-Pliocene Warm Period (mPWP) (ca. 3.3–3.0 Ma). We simulate the mPWP using the "alternate" protocol prescribed by the Pliocene Model Intercomparison Project (PlioMIP) for the AOGCM simulation (Experiment 2). Results from the CCSM4 mPWP simulation show a 1.9 °C increase in global mean annual temperature compared to the 1850 preindustrial control, with a polar amplification of ~3 times the global warming. Global precipitation increases slightly by 0.09 mm day−1 and the monsoon rainfall is enhanced, particularly in the Northern Hemisphere (NH). Areal sea ice extent decreases in both hemispheres but persists through the summers. The model simulates a relaxation of the zonal sea surface temperature (SST) gradient in the tropical Pacific, with the El Niño–Southern Oscillation (Niño3.4) ~20% weaker than the preindustrial and exhibiting extended periods of quiescence of up to 150 yr. The maximum Atlantic meridional overturning circulation and northward Atlantic oceanic heat transport are indistinguishable from the control. As compared to PRISM3, CCSM4 overestimates Southern Hemisphere (SH) sea surface temperatures, but underestimates NH warming, particularly in the North Atlantic, suggesting that an increase in northward ocean heat transport would bring CCSM4 SSTs into better alignment with proxy data.

scholarly journals The influence of Arctic air masses on climatic conditions of the snow accumulation period in the center of the European territory of Russia

2021 ◽  
pp. 16-25
Author(s):  
Julia Nikolaevna Chizhova
Keyword(s):  
North Atlantic ◽  
Arctic Oscillation ◽  
Winter Precipitation ◽  
Climatic Conditions ◽  
The Arctic ◽  
Air Masses ◽  
The North ◽  
The Arctic Oscillation ◽  
The North Atlantic Oscillation ◽  
The Relationship

The subject of this article is exmination of the influence of the Arctic air flow on the climatic conditions of the winter period in the center of the European territory of Russia (Moscow). In recent years, the question of the relationship between regional climatic conditions and such global circulation patterns as the North Atlantic Oscillation (NAO) and the Arctic Oscillation (AK) has become increasingly important. Based on the data of long-term observations of temperature and precipitation, the relationship with the AK and NAO was considered. For the winter months of the period 2014-2018, the back trajectories of the movement of air masses were computed for each date of precipitation to identify the sources of precipitation. The amount of winter precipitation that forms the snow cover of Moscow has no connection with either the North Atlantic Oscillation or the Arctic Oscillation. The Moscow region is located at the intersection of the zones of influence of positive and negative phases of both cyclonic patterns (AK and NAO), which determine the weather in the Northern Hemisphere. For the winter months, a correlation between the surface air temperature and NAO (r = 0.72) and AK (r = 0.66) was established. Winter precipitation in the center of the European territory of Russiais mainly associated with the unloading of Atlantic air masses. Arctic air masses relatively rarely invade Moscow region and bring little precipitation (their contribution does not exceed 12% of the total winter precipitation).

The role of climate on floristic composition in a latitudinal gradient in the Brazilian Atlantic Forest

2018 ◽  
Vol 151 (3) ◽  
pp. 303-313 ◽  
Author(s):  
Eduardo Magalhães Borges Prata ◽  
Aloysio De Pádua Teixeira ◽  
Carlos Alfredo Joly ◽  
Marco Antonio Assis
Keyword(s):  
Species Composition ◽  
Species Distribution ◽  
Latitudinal Gradient ◽  
Floristic Composition ◽  
Annual Rainfall ◽  
Mean Annual Temperature ◽  
Brazilian Atlantic Forest ◽  
The North ◽  
Latitudinal Range

Background and aims – Latitudinal gradients have an important influence on species distribution reflecting the effects of environmental factors such as temperature, rainfall, soil, and geographical distance. In the southeastern Brazilian Atlantic Forest, the role of climatic variables in the floristic composition is better known for altitudinal gradients of the Serra do Mar Mountains rather than for the latitudinal gradient. Here, we investigated the effects of mean annual temperature and rainfall on tree species distribution and composition in a latitudinal gradient in the Atlantic forest.Methods – We calculated each species frequency of occurrence and the latitudinal range. We used multivariate analyses (direct ordination, Hierarchical Clustering followed by Indicator Species analysis and NMDS) to investigate variation in floristic composition, and regression analyses to evaluate mean annual temperatures and rainfall effects on tree species composition along the latitudinal gradient (21°S to 28°S).Key results – A total of 789 species were registered, of which a majority (646 species) were present in less than 20% of the sampled areas, and only four species (0.5%) were present in more than 80% of the sampled areas. Only ten species (1.3%) reached the maximum latitudinal range (~6°). We found a strong correlation between variation in floristic composition and the spatial position in the latitudinal gradient. The cluster analyses detected two main floristic groups, one composed by the forests from Rio de Janeiro (21°S to 23°S) and the second by the forests from São Paulo, Paraná and Santa Catarina States (23°S to 28°S). The multiple regression analysis revealed a strong effect of the climatic variables on the variation of the floristic composition along the latitudinal gradient (r2 = 0.81, P < 0.001), where 62.82% of the variation were explained by mean annual temperature, 8.27% by annual rainfall and 10.45% by both variables together.Conclusions – The restricted distribution of most species may be explained by variations in mean annual temperature and annual rainfall along the latitudinal gradient. For instance, the decreasing mean annual temperature along the coast and the occurrence of frosts at higher latitudes may limit the southward distribution of some species while the lower annual rainfall (with marked seasonality) in the north of the gradient may limit the northward distribution of other species. Although mean annual temperature explained most of the variation in species composition along the latitudinal gradient, the abrupt variation in annual rainfall may explain the high floristic dissimilarity detected in the north of the gradient.

Frost-Resistant Elastomeric Nanocomposites for Operation in the Far North Conditions

2019 ◽  
Vol 945 ◽  
pp. 412-416
Author(s):  
Natalia N. Petrova ◽  
V.V. Portnyagina ◽  
V.V. Mukhin ◽  
E.N. Timofeeva ◽  
N.V. Matveeva ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Climatic Conditions ◽  
The Arctic ◽  
New Mineral ◽  
Detonation Synthesis ◽  
Hydrocarbon Production ◽  
The North ◽  
Elastomeric Materials ◽  
Northern Territories ◽  
Bentonite Clays

Operation of elastomeric materials in the extreme climatic conditions of the North is a complex and expensive, since not always existing materials can provide the required level of low-temperature characteristics (down to-60 ° C). This leads to failure of machines and mechanisms, equipment downtime, additional costs for repair or replacement of rubber parts. The need for such materials is continuously growing due to the intensive development of the northern territories, the need to develop new mineral deposits and development of offshore hydrocarbon production. Propylene oxide rubber (Tg = -73 °С) and epichlorohydrin rubber Hydrin T6000 (Tg = -60 °С) have unique frost resistance, but there is a need to improve aggressive media resistance, wear resistance and relaxation properties (the ability to restore its shape after relieving the load). For the modification of rubbers, additives of both organic and inorganic nature were chosen: ultrafine polytetrafluoroethylene, single-walled and multi-walled carbon nanotubes, nanodiamond-containing carbon charge obtained by detonation synthesis, shungite, natural zeolites and bentonite clays. The operating properties of rubber were studied in accordance with standard methods. The structure of the obtained materials was studied by means of DSC, XRD, electron and atomic force microscopy. All developed materials are recommended for use in various industries (oil and gas, road, rail) in the Arctic regions with extreme climatic conditions.

scholarly journals Differentiation of normative standards of budgetary appropriations for the maintenance of winter roads in the North of Russia

2021 ◽  
Vol 112 ◽  
pp. 00004
Author(s):  
Elena Eduardovna Grigoryeva ◽  
Evgeniy Petrovich Grigoryev
Keyword(s):  
Russian Federation ◽  
Climatic Conditions ◽  
The Arctic ◽  
Special Role ◽  
The North ◽  
Northern Regions ◽  
The Russian Federation ◽  
Regional Authorities ◽  
Conditions Of Work ◽  
Regions Of Russia

The article discusses the results of a study of the issues of maintaining highways of regional and intermunicipal importance in the northern regions of Russia. A special role in the article is given to the category of highways as land and ice winter roads. In the hard-to-reach areas of the Arctic and North of Russia, winter roads are the most important element of the transport system. The maintenance and service of winter roads are the responsibility of the regional authorities. The existing issue of insufficient budgetary support for the maintenance of winter roads is, inter alia, associated with the imperfection of the methodology for calculating target norms of budgetary appropriations. The article presents well-reasoned facts and substantiation of the need to update the norms of budgetary appropriations for the maintenance of winter roads, taking into account difficult territorial natural and climatic conditions of work and transport accessibility of goods delivery. Recommendations are given for changing the methodology for calculating monetary costs for the maintenance of winter roads of regional and intermunicipal importance when determining the amount of appropriations from the budget of the constituent entities of the Russian Federation.

scholarly journals Transformation Processes and Nutrition Factor in the Far North Residents' Resilience System

2021 ◽  
pp. 190-214
Author(s):  
Tatyana I. TROSHINA ◽  
◽  
Olga M. MOROZOVA ◽  
Nadezhda A. VOROBYEVA ◽  
◽  
...  
Keyword(s):  
Indigenous Peoples ◽  
Social Research ◽  
World Order ◽  
Climatic Conditions ◽  
The Arctic ◽  
Modern World ◽  
Way Of Life ◽  
Data Set ◽  
The North ◽  
Short Period

One of the global challenges of our time is the conflict of man and human communities with the rapidly changing world order, which has an aspect lying at the intersection of culture and human physiology — the conformity of food behavior to lifestyle and the environment. The vitality and resilience of modern humans is subjected to special challenges. Comfortable conditions of existence in the modern world have a reverse side, expressed in diseases associated with sedentary lifestyle, psychotraumatization, violation of the usual nutrition pattern. These changes are especially noticeable on the example of indigenous peoples of the North, who have lived in relative isolation for a long time, as well as on the example of migrants forced to work in unusual natural and climatic conditions and, in general, abruptly and for a relatively short period of time (which does not allow "launching" the adaptation mechanisms) to change the whole habitual way of life. These categories of population are of special interest for researchers, including in connection with the reactions of body to changes in the food model. The idea of optimal food for the human body, formed in the course of nutriological studies, often contradicts the food traditions of peoples living in conditions far from being favourable. Since the end of the 19th century, balanced consumption of fats, proteins and carbohydrates was perceived as a civilization sign of mature modern society, and any deviations were treated as primitive practices. Over time, the approach to studying the lifestyle of traditional societies evolved from the perspective of the mechanism of human adaptation to different habitats. Traditions, including eating habits, are regarded as an optimum point of survival with the highest level of food, fuel and other material resources available in a given habitat. In addition to the problems of traditional and modernized food supply, the article focuses on the painful conditions associated with the disruption of the habitual way of life, work and nutrition of various groups of northern residents — in historical retrospect and at the present stage. Archive and literary sources, results of modern medical and social research and own field material (ethnosociological and biomedical) were used for the analysis. As a result of the generalization of the data set, which includes the authors' own research, it has been concluded that, in addition to ensuring the supply of basic foodstuffs, preventive medicines and high-quality preventive medicine for permanent residents and temporary workers in the Arctic, it is advisable to take into account the survival practices of indigenous peoples that have been developed over the centuries, creating the conditions for new settlers for assimilation. The credibility of these traditions is given by their high viability and their focus on the ethnic survival of indigenous people in the North.

The intensity of the accumulation of residual deformations in the railway track operated in complex natural and climatic conditions

2020 ◽  
pp. 24-34
Author(s):  
L. S. Blazhko ◽  
◽  
E. V. Chernyaev ◽  
V. A. Chernyaeva ◽  
V. V. Ganchits ◽  
...  
Keyword(s):  
Practical Importance ◽  
Strength Properties ◽  
Climatic Conditions ◽  
Railway Track ◽  
The Arctic ◽  
Track Structure ◽  
Arctic Circle ◽  
Railway Line ◽  
The North ◽  
Residual Deformations

Objective: To analyze the results of observations conducted to assess the intensity of the accumulation of residual deformations in the railway track structure operated in severe natural and climatic conditions (the observation site is located above the Arctic Circle). The following were also taken into account: the railway track design (type of intermediate fasteners, track slab, condition of the ballast bed), the railway line scheme, the tonnage handled, the train speed and the axle load. Methods: Mathematical statistics, data processing. Results: The dependences of the railway track deformation and strength properties, including the tonnage handled, have been obtained. Practical importance: The presented observation results of the assessment of the intensity of deformation accumulation in the railway track structure operated in the severe natural and climatic conditions of the North of the Arctic Circle indicate that the use of increased axle load wagons will entail a significant reduction in overhaul life and an increase in the track maintenance operating expenditures

scholarly journals Massive deposition of Sahelian dust on the Canary Island Lanzarote during North Atlantic Heinrich Events

2021 ◽  
pp. 1-16
Author(s):  
Hartmut Heinrich ◽  
Christoph Schmidt ◽  
Florian Ziemen ◽  
Uwe Mikolajewicz ◽  
Christopher-Bastian Roettig
Keyword(s):  
North Atlantic ◽  
North Atlantic Ocean ◽  
Climatic Variability ◽  
Climatic Conditions ◽  
Land Snails ◽  
The Arctic ◽  
Glacial Cycle ◽  
Heinrich Events ◽  
The North ◽  
Atmospheric Changes

Abstract New IRSL ages of eolianites close to Muñique (Lanzarote) demonstrate the influence of millennial scale climatic variability on the sedimentary dynamics on the Canary Islands during the last glacial cycle. The repetitive succession of interstadial and stadial climatic conditions formed multiple sequences of eolian deposits, each in general comprising three depositional types. DepoType 1 and DepoType 2 consist mainly of marine biogenic carbonate detritus with small amounts of dust from the Sahara representing interstadial conditions. DepoType 2 compared to DepoType 1 is characterized by larger amounts of land snails and calcified brood cells. A DepoType 3 rich in dust from African subtropical/tropical Latisols terminates a sequence. IRSL dating on DepoType 3 type deposits clearly shows that these were deposited during Heinrich Events under stadial conditions. The stadial cooling of the North Atlantic Ocean caused a southern shift of climate zones that culminated during Heinrich Events when the arctic climate reaches its most southerly extent. As a consequence, atmospheric changes led to massive dust supply from the then-dry Sahel. The increase in dust and precipitation from the dry DepoTypes 1 to the more humid DepoTypes 3 originates from a modified atmospheric dynamic during a millennial cycle.

Climate Extremes across the North American Arctic in Modern Reanalyses

2020 ◽  
pp. 1-65
Author(s):  
Alvaro Avila-Diaz ◽  
David H. Bromwich ◽  
Aaron B. Wilson ◽  
Flavio Justino ◽  
Sheng-Hung Wang
Keyword(s):  
North American ◽  
Land Surface ◽  
Climate Extremes ◽  
The Arctic ◽  
Simultaneous Increase ◽  
Climate Indices ◽  
Extreme Climate ◽  
In Situ Data ◽  
The North ◽  
North American Arctic

AbstractAtmospheric reanalyses are a valuable climate-related resource where in-situ data are sparse. However, few studies have investigated the skill of reanalyses to represent extreme climate indices over the North American Arctic, where changes have been rapid and indigenous responses to change are critical. This study investigates temperature and precipitation extremes as defined by the Expert Team on Climate Change Detection and Indices (ETCCDI) over a 17 year period (2000-2016) for regional and global reanalyses, namely the Arctic System Reanalysis version 2 (ASRv2), North American Regional Reanalysis (NARR), European Centre for Medium-Range Weather Forecasts (ECMWF) ERA5 Reanalysis, Modern-Era Retrospective analysis for Research and Applications Version 2 (MERRA2), and Global Meteorological Forcing Dataset for Land Surface Modeling (GMFD). Results indicate that the best performances are demonstrated by ASRv2 and ERA5. Compared to observations, reanalyses show the weakest performance over far northern basins (e.g., Arctic and Hudson) where observing networks are less dense. Observations and reanalyses show consistent warming with decreased frequency and intensity of cold extremes. Cold days, cold nights, frost days, and ice days have decreased dramatically over the last two decades. Warming can be linked to a simultaneous increase in daily precipitation intensity over several basins in the domain. Moreover, the North Atlantic and the Arctic Oscillations (NAO, AO) distinctly influence extreme climate indices. Thus, these findings detail the complexity of how the climate of the Arctic is changing, not just in an average sense, but in extreme events that have significant impacts on people and place.

Sign in / Sign up

Export Citation Format

Share Document