scholarly journals Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica

Nature ◽  
10.1038/20859 ◽  
1999 ◽  
Vol 399 (6735) ◽  
pp. 429-436 ◽  
Author(s):  
J. R. Petit ◽  
J. Jouzel ◽  
D. Raynaud ◽  
N. I. Barkov ◽  
J.-M. Barnola ◽  
...  
Keyword(s):  
Ice Core ◽  
The Past ◽  
History Of

scholarly journals History of desert dust deposition recorded in the Elbrus ice core

2019 ◽  
Author(s):  
Stanislav Kutuzov ◽  
Michel Legrand ◽  
Suzanne Preunkert ◽  
Patrick Ginot ◽  
Vladimir Mikhalenko ◽  
...  
Keyword(s):  
North Africa ◽  
Drought Index ◽  
Decadal Variability ◽  
Ice Core ◽  
Ice Cores ◽  
Dust Deposition ◽  
The Past ◽  
Dust Sources ◽  
Increasing Trend ◽  
History Of

Abstract. Ice cores are one of the most valuable paleo-archives. Records from the ice cores can provide information not only about the amount of dust in the atmosphere but also about dust sources and its changes in the past. A 182 m long ice core has been recovered at the western plateau of Mt. Elbrus (5115 m elevation) in 2009. This record was extended with the shallow ice core drilling in 2013. Here we present analysis of the concentrations of Ca2+, a commonly used proxy of dust, recorded in Elbrus ice core over the period 1774–2013. The calcium record reveals a quasi decadal variability with a general increasing trend. Using multiple regression analysis we found a statistically significant spatial correlation of the Elbrus Ca2+ summer concentrations and precipitation and soil moisture content in Levant region (specifically Syria and Iraq). The Ca2+ record also correlates with drought index in North Africa (r = 0.69 p 

scholarly journals 1000 year ice-core records from Berkner Island, Antarctica

2002 ◽  
Vol 35 ◽  
pp. 45-51 ◽  
Author(s):  
Robert Mulvaney ◽  
Hans Oerter ◽  
David A. Peel ◽  
Wolfgang Graf ◽  
Carol Arrowsmith ◽  
...  
Keyword(s):  
Decadal Variability ◽  
Ice Core ◽  
Ice Cores ◽  
Aerosol Deposition ◽  
Climate History ◽  
Joint Project ◽  
The Past ◽  
Annual Layer ◽  
History Of ◽  
Field Season

AbstractTwo medium-depth ice cores were retrieved from Berkner Island by a joint project between the Alfred-Wegener-Institut and the British Antarctic Survey in the 1994/95 field season. A 151m deep core from the northern dome (Reinwarthhöhe) of Berkner Island spans 700 years, while a 181 m deep core from the southern dome (Thyssenhöhe) spans approximately 1200 years. Both cores display clear seasonal cycles in electrical conductivity measurements, allowing dating by annual-layer counting and the calculation of accumulation profiles. Stable-isotope measurements (both δ18O and δD), together with the accumulation data, allow us to estimate changes in climate for most of the past millennium: the data show multi-decadal variability around a generally stable long-termmean. In addition, a full suite of major chemistry measurements is available to define the history of aerosol deposition at these sites: again, there is little evidence that the chemistry of the sites has changed over the past six centuries. Finally, we suggest that the southern dome, with an ice thickness of 950 m, is an ideal site from which to gain a climate history of the late stages of the last glacial and the deglaciation for comparison with the records from the deep Antarctic ice cores, and with other intermediate-depth cores such as Taylor Dome and Siple Dome.

The past 5000 years history of solar modulation of cosmic radiation from 10 Be and 14 C studies

1990 ◽  
Vol 330 (1615) ◽  
pp. 471-480 ◽  
Keyword(s):  
Cosmic Radiation ◽  
Ice Core ◽  
Ice Cores ◽  
Solar Modulation ◽  
Short Term ◽  
The Past ◽  
History Of ◽  
Long Term Trends ◽  
Terrestrial Biomass

10 Be is produced in a similar way as 14 C by the interaction of cosmic radiation with the nuclei in the atmosphere. Assuming that the 10 Be and 14 C variation are proportional and considering the different behaviour in the Earth system, the 10 Be concentrations in ice cores can be compared with the 14 C variations in tree rings. A high correlation is found for the short-term variations ( 14 C-Suess-wiggles). They reflect with a high probability production rate variations. More problematic is the interpretation of the long-term trends of 14 C and 10 Be. Several explanations are discussed. The reconstructed CO 2 concentrations in ice cores indicate a rather constant value (280 ± 10 p.p.m. by volume) during the past few millenia. Measurements on the ice core from Byrd Station, Antarctica, during the period 9000 to 6000 years BP indicate a decrease that might be explained by the extraction of CO 2 from the atmosphere-ocean system to build the terrestrial biomass pool during the climatic optimum.

scholarly journals The Elbrus (Caucasus, Russia) ice core record – Part 2: history of desert dust deposition

2019 ◽  
Vol 19 (22) ◽  
pp. 14133-14148 ◽  
Author(s):  
Stanislav Kutuzov ◽  
Michel Legrand ◽  
Susanne Preunkert ◽  
Patrick Ginot ◽  
Vladimir Mikhalenko ◽  
...  
Keyword(s):  
Middle East ◽  
Decadal Variability ◽  
Southern Oscillation ◽  
Ice Core ◽  
Ice Cores ◽  
Drought Indices ◽  
Dust Deposition ◽  
The Past ◽  
Ice Core Record ◽  
History Of

Abstract. Ice cores are one of the most valuable paleo-archives. Records from ice cores provide information not only about the amount of dust in the atmosphere, but also about dust sources and their changes in the past. In 2009, a 182 m long ice core was recovered from the western plateau of Mt Elbrus (5115 m a.s.l.). This record was further extended after a shallow ice core was drilled in 2013. Here we analyse Ca2+ concentrations, a commonly used proxy of dust, recorded in these Elbrus ice records over the time period of 1774–2013 CE. The Ca2+ record reveals quasi-decadal variability with a generally increasing trend. Using multiple regression analysis, we found a statistically significant spatial correlation of the Elbrus Ca2+ summer concentrations with precipitation and soil moisture content in the Levant region (specifically Syria and Iraq). The Ca2+ record also correlates with drought indices in North Africa (r=0.67, p<0.001) and Middle East regions (r=0.71, p<0.001). Dust concentrations prominently increase in the ice core over the past 200 years, confirming that the recent droughts in the Fertile Crescent (1998–2012 CE) present the most severe aridity experienced in at least the past two centuries. For the most recent 33 years recorded (1979–2012 CE), significant correlations exist between Ca2+ and Pacific circulation indices (Pacific Decadal Oscillation, Southern Oscillation Index and Niño 4), which suggests that the increased frequency of extreme El Niño and La Niña events due to a warming climate has extended their influence to the Middle East. Evidence demonstrates that the increase in Ca2+ concentration in the ice core cannot be attributed to human activities, such as coal combustion and cement production.

scholarly journals 10,000 years of melt history of the 2015 Renland ice core, EastGreenland

2019 ◽  
Author(s):  
Tetsuro Taranczewski ◽  
Johannes Freitag ◽  
Olaf Eisen ◽  
Bo Vinther ◽  
Sonja Wahl ◽  
...  
Keyword(s):  
Ice Core ◽  
Greenland Ice Sheet ◽  
Ice Age ◽  
Strong Increase ◽  
Past Century ◽  
Additional Information ◽  
The Past ◽  
Ice Cap ◽  
History Of ◽  
Paleoclimate Records

Abstract. An ice core drilled in 2015 on the Renland ice cap at the eastern margin of Greenland has been inspected with regard to its melt content. The thickness of a melt layer reflects the temperature level at the time of melt generation. Hence the melt layers are an indicator of past regional summer temperatures in East Greenland, a region where paleoclimate records are sparse. Melt layers have been identified almost along the whole core, resulting in a melt record reaching back 10,000 years. By gathering additional information about melt rates as well as high-resolution densities in two shallow cores, we developed an approach to correct the annual melt content for the ice volume that gets lost by the thinning process. The result is a melt record with decadal- to centennial- scale resolution for the last two millennia, and the most accurate Holocene climate record for Eastern Greenland so far. The observed changes of annual melt rates show a warm early Holocene, with melt rates higher than in the recent past century, and minimum melting during the Little Ice Age. Current melt rates show a strong increase for the early 20th century as well as for the time since the end of the past century, with the recent 2012 extreme melting of the Greenland Ice Sheet being the strongest melt event in the past 500 years.

Summary

2007 ◽  
Author(s):  
Robert May
Keyword(s):  
Fossil Fuels ◽  
Industrial Revolution ◽  
Global Climate ◽  
Ice Core ◽  
Sea Levels ◽  
The Past ◽  
Energy Demands ◽  
Co2 Levels ◽  
The Usa ◽  
History Of

Energy . . . Beyond Oil is important and timely and should be understood within the wider context of global climate change and future energy demands. In the 1780s John Watts developed his steam engine and so began the Industrial Revolution. At this time, ice-core records show that levels of CO2 in the atmosphere were around 288 parts per million (ppm). Give or take 10 ppm, this had been their level for the past 6,000 years, since the dawn of the first cities. As industrialization drove up the burning of fossil fuels in the developed world, CO2 levels rose. At first the rise was slow. It took about a century and a half to reach 315 ppm. The rise accelerated during the twentieth century: 330 ppm by the mid-1970s; 360 ppm by the 1990s; 380 ppm today. This change of 20 ppm over the past decade is equal to that last seen when the most recent ice age ended, ushering in the dawn of the Holocene epoch, 10,000 years ago. If current trends continue, then by about 2050 atmospheric CO2 levels will have reachedaround500 ppm, nearly double pre-industrial levels. The last time our planet experienced such high levels was some 50 million years ago, during the Eocene epoch, when sea levels were around100 m higher than today. The Dutch Nobelist, Paul Crutzen, has, indeed, suggested that we should recognize that we are now living in a new geological epoch, the Anthropocene. He sees this epoch as beginning around 1780, when industrialization began to change the geochemical history of our planet. Even today, there continues to exist a ‘denial lobby’, funded to the tune of tens of millions of dollars by sectors of the petrochemical industry, and highly influential in some countries. This lobby has understandable similarities, in tactics and attitudes, to the tobacco lobby that continues to deny smoking causes lung cancer, or the curious lobby denying that HIV causes AIDS. This denial lobby is currently very influential in the USA.

On The Possibility of an Autonomous History of Modern Southeast Asia

1961 ◽  
Vol 2 (2) ◽  
pp. 73-105 ◽  
Author(s):  
John R. W. Small
Keyword(s):  
Southeast Asia ◽  
Contemporary History ◽  
The Past ◽  
History Of

It is generally accepted that history is an element of culture and the historian a member of society, thus, in Croce's aphorism, that the only true history is contemporary history. It follows from this that when there occur great changes in the contemporary scene, there must also be great changes in historiography, that the vision not merely of the present but also of the past must change.

Stellar Evolution

1962 ◽  
Vol 11 (02) ◽  
pp. 137-143
Author(s):  
M. Schwarzschild
Keyword(s):  
Solar System ◽  
Stellar Evolution ◽  
Space Craft ◽  
New Techniques ◽  
Substantial Body ◽  
Individual Stars ◽  
The Past ◽  
Evolution Of Galaxies ◽  
History Of ◽  
Fast Flow

It is perhaps one of the most important characteristics of the past decade in astronomy that the evolution of some major classes of astronomical objects has become accessible to detailed research. The theory of the evolution of individual stars has developed into a substantial body of quantitative investigations. The evolution of galaxies, particularly of our own, has clearly become a subject for serious research. Even the history of the solar system, this close-by intriguing puzzle, may soon make the transition from being a subject of speculation to being a subject of detailed study in view of the fast flow of new data obtained with new techniques, including space-craft.

A 200-Year History of the Study of Childhood Language Disorders of Unknown Origin: Changes in Terminology

2020 ◽  
Vol 5 (1) ◽  
pp. 6-11 ◽  
Author(s):  
Laurence B. Leonard
Keyword(s):  
Language Impairment ◽  
Specific Language Impairment ◽  
Scientific Literature ◽  
Language Disorder ◽  
Language Disorders ◽  
Unknown Origin ◽  
Developmental Language Disorder ◽  
The Past ◽  
History Of ◽  
The Many

Purpose The current “specific language impairment” and “developmental language disorder” discussion might lead to important changes in how we refer to children with language disorders of unknown origin. The field has seen other changes in terminology. This article reviews many of these changes. Method A literature review of previous clinical labels was conducted, and possible reasons for the changes in labels were identified. Results References to children with significant yet unexplained deficits in language ability have been part of the scientific literature since, at least, the early 1800s. Terms have changed from those with a neurological emphasis to those that do not imply a cause for the language disorder. Diagnostic criteria have become more explicit but have become, at certain points, too narrow to represent the wider range of children with language disorders of unknown origin. Conclusions The field was not well served by the many changes in terminology that have transpired in the past. A new label at this point must be accompanied by strong efforts to recruit its adoption by clinical speech-language pathologists and the general public.

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