Aerosol particle formation events and analysis of high growth rates observed above a subarctic wetland–forest mosaic     

BIRGITTA SVENNINGSSON  ALMUT ARNETH  SEAN HAYWARD  THOMAS HOLST  REAS MASSLING  ERIK SWIETLICKI  ANNE HIRSIKKO  HEIKKI JUNNINEN  ILONA RIIPINEN  MARKO VANA  MIIKKA DAL MASO  TAREQ HUSSEIN  MARKKU KULMALA 《Tellus. Series B, Chemical and physical meteorology》2008,60(3):353-364

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Simulation of atmospheric CO₂ over Europe and western Siberia using the regional scale model REMO     

ANNE CHEVILLARD  UTE KARSTENS  PHILIPPE CIAIS  SÉBASTIEN LAFONT  MARTIN HEIMANN 《Tellus. Series B, Chemical and physical meteorology》2002,54(5):872-894

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Holocene vegetation and climate history on a continental-oceanic transect in northern Fennoscandia based on pollen and plant macrofossils     

ANNE E. BJUNE  H. J. B. BIRKS  HEIKKI SEPPÄ 《Boreas: An International Journal of Quaternary Research》2004,33(3):211-223

Changes in tree-line, mean July temperature (T _jul ) and mean annual precipitation (P _ann ) for the last 10 200 cal. yr BP are reconstructed on the basis of pollen and plant macrofossils preserved in lake sediments from two sites near the present-day tree-line in Troms, northern Norway. Quantitative climate reconstructions are performed using pollen-climate transfer functions based on WA-PLS regression. Early Holocene Betula pubescens forests were gradually replaced by Pinus sylvestris at Dalmutladdo (355 m a.s.l.) starting about 7000 cal. yr BP. The local presence of pine woodland at that time is supported by finds of stomata and plant macrofossils and by high pollen accumulation rates. Until about 4000 cal. yr BP the P. sylvestris tree-line was 250-300 m higher than today, suggesting T _jul about 2.0°C higher than at present. The later part of the Holocene has a cooler and moister climate and an increasing development of mires and fern-rich vegetation, as shown by increases of Sphagnum and fern spores and the re-establishment of B. pubescens woodland. The reconstructed T _jul from the two sites shows similar trends to previously published data, with T _jul 1-2°C warmer between 9500 cal. yr BP and 2000 cal. yr BP T _jul . Maximum T _jul values occur between 8500 and 4500 cal. yr BP, after which there is a gradual decrease in T _jul .  相似文献   

Chronology and paleoenvironments during the late Weichselian deglaciation of the southwest Iceland shelf     

ANNE JENNINGS  JAMES SYVITSKI  LINDA GERSON  KARL GRÖNVOLD  ÁSLAUG GEIRSDÓTTIR  JÓRUNN HARDARDÓTTIR  JOHN ANDREWS  SVEINUNG HAGEN 《Boreas: An International Journal of Quaternary Research》2000,29(3):163-183

Foraminifera, sedimentology, and tephra geochemistry in core 93030-006 LCF from the southwestern Iceland shelf were used to reconstruct paleoenvironments between 12.7 and 9.4 ¹⁴C ka BP. Seismic-reflection profiles place the core in glacial-marine and marine sediments within one meter of the underlying glacial till. Foraminifers in the earliest glacial-marine sediments provide a record of ice-distal conditions and immigration of slope species onto the shelf in association with warm Atlantic water. Meltwater increased during the Allerød under a weakened Atlantic water influence. Arctic conditions began by 11.14 ₁₄C ka BP with an abrupt increase in meltwater and near exclusion of boreal fauna from the shelf. Meltwater diminished in the early Younger Dryas, coinciding with sea-surface cooling between 11.14 and 10.5 ¹⁴C ka BP. A slight warming recorded in the uppermost glacial-marine sediments was interrupted by an inferred jökulhlaup event emanating from glacier ice on the Western Volcanic Zone. Retreat of the ice margin from the sea sometime between c. 10.3 and 9.94 ¹⁴C ka BP coincided with this event. The onset of postglacial marine sedimentation occurred along with increasing evidence of Atlantic water c. 9.94 ¹⁴C ka BP and was interrupted by a short-lived Pre-boreal cooling of the Irminger Current c. 9.91 ¹⁴C ka BP. Conditions similar to those today were established by 9.7 ¹⁴C ka BP.  相似文献   

Numerical simulations of sea and land breezes at high latitudes     

SIGBJØRN GRØNÅS  ANNE DAGRUN SANDVIK 《地球，A辑:动力气象学与海洋学》1998,50(4):468-489

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Lateglacial and Holocene terrestrial and marine proxies reflecting climate changes in the Malangen fjord area, Norway, northeast North Atlantic     

ALLA SHARAPOVA  MORTEN HALD  KATRINE HUSUM  CHRISTIN JENSEN 《Boreas: An International Journal of Quaternary Research》2008,37(3):444-457

A high-resolution Younger Dryas–late Holocene record of climate and environment from the Malangen fjord has been established on the basis of two marine sediment cores. Five pollen-spore assemblage zones have been defined covering the period c . 11 500 cal. yr BP (10 200 ¹⁴C yr BP) to c . 1600 cal. yr BP (1600 ¹⁴C yr BP) with a hiatus of c . 2000 cal. years between c . 10 200 and 8100 cal. yr BP (9000 and 7300 ¹⁴C yr BP). The Holocene vegetation development from pioneer vegetation to forest development, identified in the marine pollen record, correlates well with pollen records from terrestrial sections of northern Norway. The marine pollen record was also correlated directly with marine proxy records of the bottom water temperature investigated in the same sediment cores. Correlation between the marine and terrestrial proxies suggests that changes in the influx of warm Atlantic Water to the fjord led to an instant change in the vegetation of the surrounding land area. The results thus support a strong link between marine and atmospheric mean climatic states in the North Atlantic region throughout the Holocene.  相似文献   

Use of radon for evaluation of atmospheric transport models: sensitivity to emissions     

MOHAN L. GUPTA  ANNE R. DOUGLASS  S. RANDOLPH KAWA  STEVEN PAWSON 《Tellus. Series B, Chemical and physical meteorology》2004,56(5):404-412

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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   

Coastal dune conservation on an Irish commonage: community-based management or tragedy of the commons?     

JOHN MC KENNA  ANNE MARIE O'HAGAN†  JAMES POWER‡  MICHAEL MACLEOD§  ANDREW COOPER 《The Geographical journal》2007,173(2):157-169

In Ireland 'commonage' refers to lands jointly owned by several individuals who have grazing rights. Commonage can provide the low-intensity grazing regime regarded as optimal for habitat conservation, and it is also unlikely to suffer the negative impacts of building development or coastal engineering. Today, however, the traditional control systems of coastal commonage are generally moribund, leading to habitat degradation. The only viable future management model is likely to be one based on local community control. Community management would have the legitimacy to counter the negative perceptions of external authority that generate environmental degradation.  相似文献   

Aerosol size distribution measurements at four Nordic field stations: identification, analysis and trajectory analysis of new particle formation bursts   总被引：2，自引：5，他引：2  

MIIKKA DAL MASO  LARISA SOGACHEVA  PASI P. AALTO  ILONA RIIPINEN  MIKA KOMPPULA  PETER TUNVED  LAURA KORHONEN  VILLE SUUR-USKI  ANNE HIRSIKKO  THEO KURTÉN  VELI-MATTI KERMINEN  HEIKKI LIHAVAINEN  YRJÖ VIISANEN  HANS-CHRISTEN HANSSON  MARKKU KULMALA 《Tellus. Series B, Chemical and physical meteorology》2007,59(3):350-361

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