Two Creeks Interstade Dated through Dendrochronology and AMS

1994 ◽  
Vol 42 (3) ◽  
pp. 288-298 ◽  
Author(s):  
Klaus Felix Kaiser

AbstractDendrochronological analysis of fossil wood from Two Creeks, Wisconsin, reveals that the Two Creekan Intetstade lasted at least 252 yr. The sites crossdated by tree rings cover an area of about 970 km2. AMS determinations from the beginning and end of the chronology open a 14 C time window for the episode from 12,050 to 11,750 yr B.P. The interval is contemporaneous with the Older Dryas in northern Europe. The development of a forest covering at least 970 km2 on the western shore of Lake Michigan indicates a water level about as low as in modern times. Glacier retreat must have opened drainage channels either through the Straits of Mackinac or via the Indian River Plateau into the eastern lakes. The beginning of the tree-ring chronology coincides with the peak of meltwater pulse 1A at 12,000 yr B.P. Increased amounts of meltwater seem to have disturbed the heat exchange between the waters and the atmosphere in the North Atlantic off the Gulf of St. Lawrence or affected the δ18O-ratio of the evaporation, causing the climatic or isotopic reversal of the Older Dryas in Greenland and northern Europe.

2020 ◽  
Vol 32 (1) ◽  
Author(s):  
Peifang Leng ◽  
Fadong Li ◽  
Kun Du ◽  
Zhao Li ◽  
Congke Gu ◽  
...  

Abstract Background Groundwater is typically over-saturated in CO2 with respect to atmospheric equilibrium. Irrigation with groundwater is a common agricultural practice in many countries, but little is known about the fate of dissolved inorganic carbon (DIC) in irrigation groundwater and its contribution to the CO2 emission inventory from land to the atmosphere. We performed a mesocosm experiment to study the fate of DIC entering agricultural drainage channels in the North China Plain. Specifically, we aimed to unravel the effect of flow velocity and nutrient on CO2 emissions. Results All treatments were emitting CO2. Approximately half of the DIC in the water was consumed by TOC production (1–16%), emitted to the atmosphere (14–20%), or precipitated as calcite (CaCO3) (14–20%). We found that DIC depletion was stimulated by nutrient addition, whereas more CO2 evasion occurred in the treatments without nutrients addition. On the other hand, about 50% of CO2 was emitted within the first 50 h under high flow velocity. Thus, in the short term, high nutrient levels may counteract CO2 emissions from drainage channels, whereas the final fate of the produced biomass (burial versus mineralization to CO2 or even CH4) determines the duration of the effect. Conclusion Our study reveals that both hydrology and biological processes affect CO2 emissions from groundwater irrigation channels. The estimated CO2 emission from total groundwater depletion in the North China Plain is up to 0.52 ± 0.07 Mt CO2 year−1. Thus, CO2 emissions from groundwater irrigation should be considered in regional CO2 budgets, especially given that groundwater depletion is expected to acceleration in the future.


Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 430 ◽  
Author(s):  
Ronald S. Zalesny ◽  
Andrej Pilipović ◽  
Elizabeth R. Rogers ◽  
Joel G. Burken ◽  
Richard A. Hallett ◽  
...  

Poplar remediation systems are ideal for reducing runoff, cleaning groundwater, and delivering ecosystem services to the North American Great Lakes and globally. We used phyto-recurrent selection (PRS) to establish sixteen phytoremediation buffer systems (phyto buffers) (buffer groups: 2017 × 6; 2018 × 5; 2019 × 5) throughout the Lake Superior and Lake Michigan watersheds comprised of twelve PRS-selected clones each year. We tested for differences in genotypes, environments, and their interactions for health, height, diameter, and volume from ages one to four years. All trees had optimal health. Mean first-, second-, and third-year volume ranged from 71 ± 26 to 132 ± 39 cm3; 1440 ± 575 to 5765 ± 1132 cm3; and 8826 ± 2646 to 10,530 ± 2110 cm3, respectively. Fourth-year mean annual increment of 2017 buffer group trees ranged from 1.1 ± 0.7 to 7.8 ± 0.5 Mg ha−1 yr−1. We identified generalist varieties with superior establishment across a broad range of buffers (‘DM114’, ‘NC14106’, ‘99038022’, ‘99059016’) and specialist clones uniquely adapted to local soil and climate conditions (‘7300502’, ‘DN5’, ‘DN34’, ‘DN177’, ‘NM2’, ‘NM5’, ‘NM6’). Using generalists and specialists enhances the potential for phytoremediation best management practices that are geographically robust, being regionally designed yet globally relevant.


Antiquity ◽  
1949 ◽  
Vol 23 (91) ◽  
pp. 129-135 ◽  
Author(s):  
V. G. Childe

Till 1948 the coherent record of farming in Northern Europe began with the neolithic culture represented in the Danish dysser (‘dolmens’) and most readily defined by the funnel-necked beakers, collared flasks and ‘amphorae’ found therein. As early as 1910 Gustav Kossinna had remarked that these distinctive ceramic types, and accordingly the culture they defined, were not confined to the West Baltic coastlands, but recurred in the valleys of the Upper Vistula and Oder to the east, to the south as far as the Upper Elbe and in northwest Germany and Holland too. He saw in this distribution evidence for the first expansion of Urindogermanen from their cradle in the Cimbrian peninsula. In the sequel Åberg filled in the documentation of this expansion with fresh spots on the distribution map and Kossinna himself distinguished typologically four main provinces or geographical groups—the Northern, Eastern, Southern and Western. Finally Jazdrzewski gave a standard account of the whole content of what had come to be called Kultura puharów lejkowatych, Trichterbecherkultur, or Tragtbaegerkulturen. As ‘Funnel-necked-beaker culture’ is a clumsy expression and English terminology is already overloaded with ‘beakers’, I shall use the term ‘First Northern’.The orgin of this vigorous and expansive group of cultivators and herdsmen has always been an enigma. Not even Kossinna imagined that the savages of the Ertebølle shell-mounds spontaneously began cultivating cereals and breeding sheep in Denmark. As dysser were regarded as megalithic tombs and as megaliths are Atlantic phenomena, he supposed that the bases of the neolithic economy were introduced from the West together with the ‘megalithic idea’. But the First Northern Farmers of the South and East groups did not build megalithic tombs. Moreover, in the last ten years an extension of the North group across southern Sweden as far as Södermannland has come to light, and these farmers too, though they used collared flasks and funnel-necked beakers, built no dolmens either. In any case there was nothing Western about the pottery from the Danish dysser, and Western types of arrow-head are conspicuously rare in Denmark.


Polar Record ◽  
1983 ◽  
Vol 21 (135) ◽  
pp. 559-567 ◽  
Author(s):  
Franz Selinger ◽  
Alexander Glen

By autumn 1940 the first round of fighting in World War II was over. In northern Europe, German forces occupied Poland, Norway and Denmark. Both sides recognized that further operations demanded naval and air superiority in northern waters. Germany needed free access to the Atlantic Ocean through the North Sea; Britain had to prevent that access, which threatened the lifeline to the United States. More than ever before, it became essential for both sides to have meteorological information from the northern Atlantic Ocean area. Germany's need was especially acute, for the routes for her shipping from ports in Scandinavia traversed enemy-patrolled waters, where foul weather was essential for evasion.


2020 ◽  
Vol 73 (1) ◽  
pp. 103-111
Author(s):  
D. Kalibekuly ◽  
◽  
Y.S. Chukubayev ◽  

The paper examines the dynamics of regional security in Norway as a part of Northern Europe. Being a political and geographical part of the Euro-Atlantic security system. Northern Europe, in its turn, is experiencing the impact of the confrontation between Russia and NATO. Norway's security policy analyzed from the perspective of a regional leader, as a NATO member country participating in the operations of the North Atlantic Alliance and as NATO's northern wing.


1980 ◽  
Vol 70 (4) ◽  
pp. 1199-1223
Author(s):  
Robert E. Wallace ◽  
Ta-Liang Teng

abstract On August 16, 22, and 23, 1976, a succession of three large earthquakes (M = 7.2, 6.8, 7.2) occurred in the Sungpan-Pingwu area of Szechuan Province, People's Republic of China. Their successful predictions resulted in a substantial reduction in the loss of lives. The epicenters of these events progressed from north to south along the Huya Fault, a NNW-striking fault between the NE-trending Lungmenshan fracture zone and the north-trending Mienchiang fracture zone in western Szechuan. The greatest intensity reported was IX; isoseismals were crudely elliptical with the long axis parallel to the trend of the Huya Fault. The predictions were made with a reasonably good magnitude window (less than 0.5 magnitude unit), a rather large space window (about 150 km ×150 km), and a remarkably good time window (within a day). The detailed prediction process began with field monitoring some 6 yr before the Sungpan-Pingwu events and ended with the final issuance of warning and mass evacuation. During the few weeks preceding the earthquakes, about 1,300 observations of noninstrumental anomalies and precursory phenomena were reported by scientists and lay brigades: outgassings, fireballs and other earthquake lights, abnormal animal and plant behavior, and telluric currents.


2017 ◽  
Vol 51 (3) ◽  
pp. 221-242 ◽  
Author(s):  
S. J. Rahmat ◽  
I. A. Koretsky ◽  
J. E. Osborne ◽  
A. A. Alford

Abstract The Family Phocidae includes four subfamilies (Phocinae, Monachinae, Cystophorinae, and Devinophocinae) consisting of mediumto large-sized mammals that possess distinctive adaptations to semi-aquatic life. In the Miocene of the Chesapeake Group, only two subfamilies of the Family Phocidae were identified: Phocinae and Monachinae. Leptophoca, a representative of the subfamily Phocinae, appears on the eastern shore of the North Atlantic around 16 million years ago. Recently, two new monachine species, the larger Terranectes magnus (n. gen., n. sp.) and the medium-sized T. parvus (n. sp.), were recorded in the Upper Miocene of the Chesapeake Group in the Eastover Formation (7.0–6.0 Ma) and St. Marys Formation (10.0-8.0 Ma). These two distinct subfamilies of seals indicate a well-marked divergence between phocines and monachines, much earlier than 18 million years ago, as previously suggested. The Eastover Formation was deposited in a shallow embayment that covered southern Maryland, the coastal plain of Virginia, and the northeastern corner of North Carolina. The geologically older St. Marys Formation represents a tide-influenced coastal environment, with low-salinity estuaries. There was a sharp temperature decrease in the Late Miocene, indicated by a shift to a cooler-water fish fauna during St. Marys time. The Eastover Formation reflects warmer waters with relatively strong currents, significant shoals, barriers, and varied depths. Fossil evidence of earlier seals suggests that phocids originated in the North Atlantic and otarioids in the North Pacific. True seals diverged from ancient Carnivora in the early Oligocene (or earlier) in the Paratethyan / Mediterranean Basins, spread widely during the Middle Miocene and crossed westward across the Atlantic Ocean, before dispersing in the eastern United States by the Early Pliocene.


2019 ◽  
pp. 158-184
Author(s):  
Robert Chazan

This chapter considers Jewish settlement in northern Europe. Since Jews were newcomers, and since newcomers are regularly resented by the indigenous populace, much of the new reality and new status was decidedly limited and limiting, inferior to the well-established reality and status enjoyed by Jews in their older areas of habitation. The newness of the Jews of the north stimulated innovative configurations of Jewish economic activity, altered popular imagery of Jews, created difficult social relations between the Jews and their non-Jewish neighbors, fostered altered Church stances toward Judaism and Jews, and fashioned new relationships between the political authorities and their Jewish clients.


2014 ◽  
Vol 31 (1) ◽  
pp. 61-68 ◽  
Author(s):  
Samuli Helama ◽  
Jari Holopainen ◽  
Mauri Timonen ◽  
Kari Mielikäinen

Abstract A near-millennial tree-ring chronology (AD 1147-2000) is presented for south-west Finland and analyzed using dendroclimatic methods. This is a composite chronology comprising samples both from standing pine trees (Pinus sylvestris L.) and subfossil trunks as recovered from the lake sediments, with a total sample size of 189 tree-ring sample series. The series were dendrochronologically cross-dated to exact calendar years to portray variability in tree-ring widths on inter-annual and longer scales. Al though the studied chronology correlates statistically significantly with other long tree-ring width chronologies from Finland over their common period (AD 1520-1993), the south-west chronology did not exhibit similarly strong mid-summer temperature or spring/early-summer precipitation signals in comparison to published chronologies. On the other hand, the south-west chronology showed highest correlations to the North Atlantic Oscillation indices in winter/spring months, this association following a dendroclimatic feature common to pine chronologies over the region and adjacent areas. Paleoclimatic comparison showed that tree-rings had varied similarly to central European spring temperatures. It is postulated that the collected and dated tree-ring material could be studied for wood surface reflectance (blue channel light intensity) and stable isotopes, which both have recently shown to correlate notably well with summer temperatures.


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