A model‐based diagnostic study of the development and maintenance mechanism of two polar lows     

THOR ERIK NORDENG 《地球，A辑:动力气象学与海洋学》1990,42(1):92-108

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Establishing a geographical information system in relation to its use A process of strategic choices†     

W. H. ERIK DE MAN 《International journal of geographical information science》2013,27(3):245-261

Abstract

The planning and establishment of a geographical information system (GIS) relates to its context and intended use. GIS are a specialized type of information system, typically dealing with spatial data. This paper explores the environment of an envisaged GIS; the information utilization system and the wider object system. The planning and design of a GIS go beyond technical issues; they also have to take behavioural and organizational aspects of the utilization of information into account and contribute to a process of organizational development The paper is in two parts. The first (§ 2) explores salient aspects in the planning and design process, the second ( § 3) suggests some guidance in this task. The suggested approach of strategic choice in planning and establishing a GIS is designed to cope with the prevailing uncertainties in this planning process. It distinguishes between those decisions which have to be taken at once and choices which may be left open for the future.  相似文献   

A regional numerical sulfur dispersion model using a meteorological model with explicit treatment of clouds     

ERIK. BERGE 《Tellus. Series B, Chemical and physical meteorology》1990,42(5):389-407

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Status of the Atlantic walrus Odobenus rosmarus rosmarus in the Svalbard area     

ERIK W. BORN 《Polar research》1984,2(1):27-45

Observations of walrus in the Svalbard area in the period 1954-1982 indicate an increase since 1970 in the numbers summering in this area. The numbers of walrus observed show annual fluctuations. With the exception of 1973, when at least 300 animals were observed on one occasion at Kvitøya, the observations indicate a summering stock of about 100 animals. In 1982, when most walrus habitats in Svalbard were surveyed, observations of 248-274 animals were recorded. These observations were estimated to represent 82–85 individuals.
During summer, walrus are most frequently observed at Tusenøyane, in Murchisonfjorden and along adjacent coasts, along the northern coast of Nordaustlandet, at Kvitoya, and at Moffen. Apparently, the walrus re-established the use of Moffen as a summer haul-out site about the beginning of the 1970s.
An apparent under-representation of observations of females with dependent calves in Svalbard indicates that the area is mainly used as a summering area by males and that Svalbard is in the process of being repopulated by an extension of a population centred elsewhere. It is suggested that the walrus summering in Svalbard belong to a population with its main distribution in the Frans Josef Land archipelago, but at least some may be derived from a walrus population(s) occurring at Novaja Zemlja and in the Kara Sea.  相似文献   

Glacial history and shoreline displacement on Erdmannflya and Bohemanflya, Spitsbergen, Svalbard     

OTTO SALVIGSEN  ANNE ELGERSMA  CHRISTIAN HJORT  ERIK LAGERLUND  OLAV LIESTØL  NILS-OLOF SVENSSON 《Polar research》1990,8(2):261-273

Traces of former glaciation were studied on Erdmannflya and Bohemanflya. Both peninsulas were probably completely covered by glaciers during the Late Weichselian and the final dcglaciation took place around years BP. Esmarkbreen readvanced shortly after 9,500 BP, probably a local and shortlasting event. Raised beaches occur to about 60 m above sea level, and date back to about 10,000 BP. Initial land emergence was rapid, about 3m/100 years. It seems to have been followed by a marine transgression between 8,500 and 7,500 BP, which resulted in a large and distinct beach bridge and marine abrasion cliffs about 10-12 m above present sea level. Mytilus edulis lived in the area between at least 9.000 and 5,000 BP. Five thousand years ago relative sea level probably stood 3-4 m higher than today. Relative sea level has remained close to present during the last centuries. Different positions of glacier fronts in this century have also been mapped.  相似文献   

Weichselian till stratigraphy in borings from northern Falster, Denmark     

ERIK MAAGAARD JACOBSEN 《Boreas: An International Journal of Quaternary Research》1981,10(4):403-409.

A detailed lithological and petrographical investigation of 102 borings across the island of Falster, Denmark, shows that four till-beds can be distinguished. The borings are on both sides of the recessional ice border line of the G-stage of the Young Baltic Ice. The stratigraphy indicates that the morphological petrographical parameters show regional significance in differentiating the two uppermost tills. The upper one is referred to the Weichselian Young Baltic advance on the basis of stone counts and till fabrics. The lower one is referred to the Weichselian Northeast advance on the basis of stone counts and the orientation of a chalk floe. In one boring additional till-beds were recognized, one of which referred to the Weichselian Old Baltic advance, because of the clast petrography and content of reworked Eemian foraminifera. The lowermost till is interpreted as being of Saalean age on the basis of the counts of the tine gravel fraction (3–5 mm). The landscape is dominated by the morphology produced by the Northeast Ice advance, whereas the later Young Baltic advance had only a drumlinizing effect.  相似文献   

On the effects of horizontal resolution and diffusion in a two-layer general circulation model with a zonally symmetric forcing     

ERIK ELIASEN  LEIF LAURSEN 《地球，A辑:动力气象学与海洋学》1990,42(5):520-530

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Holocene humidity fluctuations in Sweden inferred from dendrochronology and peat stratigraphy   总被引：1，自引：0，他引：1  

BJÖRN ERIK GUNNARSON  ERS BORGMARK  STEFAN WASTEGÅRD 《Boreas: An International Journal of Quaternary Research》2003,32(2):347-360

Tree-ring and peat stratigraphy data were examined back to 5000 BC in order to identify and compare humidity changes in Fennoscandia. The temporal variation in distribution of Scots pine ( Pinus sylvestris L.) was used as a measure of past lake-level fluctuations in central Sweden. The chronology, which spans 2893 BC–AD 1998 with minor gaps in AD 887–907 and 1633–1650 BC and with additional floating chronologies back to 4868 BC, was cross-dated and fixed to an absolute timescale using a chronology from Torneträsk, northern Sweden. The peat stratigraphy from the Stömyren peat bog, south-central Sweden, was transformed into humification indices to evaluate humidity changes during the past 8000 years. The peat chronology is established by four tephra datings and eight ¹⁴C datings. Synchronous periods of drier conditions, interpreted from regeneration and the mortality pattern of pine, tree-ring chronology and peat humification, were recognized at c. 4900–4800 BC, 2400–2200 BC, 2100–1800 BC, 1500–1100 BC, AD 50–200, AD 400–600 and AD 1350–1500. Possible wetter periods were encountered at 3600–3400 BC, 3200–2900 BC, 2200–2100 BC, 1700–1500 BC, 1100–900 BC, 100 BC-AD 50, AD 200–400, AD 750–900 and AD 1550–1700. The wet and dry periods revealed by the tree rings and peat stratigraphy data indicate considerable humidity changes in the Holocene.  相似文献   

Polar lows and arctic instability lows in the Bear Island region   总被引：1，自引：0，他引：1  

ERIK A. RASMUSSEN  TORBEN S. PEDERSEN  LEIF T. PEDERSEN  JOHN TURNER 《地球，A辑:动力气象学与海洋学》1992,44(2):133-154

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AN ALGONKIAN CONTINENTAL SEDIMENTARY FORMATION IN WESTERN SHANSI     

E.NORIN 《地质学报》1924,3(1):55-71

The Algonkian sediments of western Shansi are represented by a sedimentary and eruptive formation of very great thickness. They consist of coarse and fine groined sandstones, generally of reddish brown and white colour, interbedded with inconsistent coarser and finer conglomerate layers and reddish brown shales. The formation is intruded by diabases, occuring partly as vertical or oblique dikes, and partly as intrusive or effusive sheets.  相似文献