scholarly journals Climatic changes in the Urals over the past millennium – an analysis of geothermal and meteorological data

2007 ◽  
Vol 3 (2) ◽  
pp. 237-242 ◽  
Author(s):  
D. Yu. Demezhko ◽  
I. V. Golovanova
Keyword(s):  
20Th Century ◽  
18Th Century ◽  
Meteorological Data ◽  
Ground Surface ◽  
Ice Age ◽  
Temperature History ◽  
Joint Analysis ◽  
The Urals ◽  
The Past ◽  
Mean Temperature

Abstract. This investigation is based on a study of two paleoclimatic curves obtained in the Urals (51–59° N, 58–61° E): i) a ground surface temperature history (GSTH) reconstruction since 800 A.D. and ii) meteorological data for the last 170 years. Temperature anomalies measured in 49 boreholes were used for the GSTH reconstruction. It is shown that a traditional averaging of the histories leads to the lowest estimates of amplitude of past temperature fluctuations. The interval estimates method, accounting separately for the rock's thermal diffusivity variations and the influence of a number of non-climatic causes, was used to obtain the average GSTH. Joint analysis of GSTH and meteorological data bring us to the following conclusions. First, ground surface temperatures in the Medieval maximum during 1100–1200 were 0.4 K higher than the 20th century mean temperature (1900–1960). The Little Ice Age cooling was culminated in 1720 when surface mean temperature was 1.6 K below the 20th century mean temperature. Secondly, contemporary warming began approximately one century prior to the first instrumental measurements in the Urals. The rate of warming was +0.25 K/100 years in the 18th century, +1.15 K/100 years in the 19th and +0.75 K/100 years in the first 80 years of the 20th century. Finally, the mean rate of warming increased in the final decades of 20th century. An analysis of linear regression coefficients in running intervals of 21 and 31 years, shows that there were periods of warming with almost the same rates in the past, including the 19th century.

scholarly journals Climatic changes in the Urals over the past millennium. An analysis of geothermal and meteorological data

2007 ◽  
Vol 3 (1) ◽  
pp. 1-17
Author(s):  
D. Yu. Demezhko ◽  
I. V. Golovanova
Keyword(s):  
20Th Century ◽  
18Th Century ◽  
Meteorological Data ◽  
Ground Surface ◽  
Ice Age ◽  
Temperature History ◽  
Joint Analysis ◽  
The Urals ◽  
The Past ◽  
Mean Temperature

Abstract. This investigation is based on a study of two paleoclimatic curves obtained in the Urals (51–59° N, 58–61° E): i) a ground surface temperature history (GSTH) reconstruction since 800 AD and ii) meteorological data for the last 170 years. Temperature anomalies measured in 49 boreholes were used for the GSTH reconstruction. It is shown that a traditional averaging of the histories leads to the lowest estimates of amplitude of past temperature fluctuations. The interval estimates method, accounting separately for the rock's thermal diffusivity variations and the influence of a number of non-climatic causes, was used for obtaining the average GSTH. Joint analysis of GSTH and meteorological data bring us to the following conclusions. First, ground surface temperatures in the Medieval maximum during 1100–1200 was 0.38 K higher than the 20th century mean temperature (1900–1960). The Little Ice Age cooling was culminated in 1720 when surface mean temperature was 1.58 K below than the 20th century mean temperature. Secondly, contemporary warming began approximately one century prior to the first instrumental measurements in the Urals. The rate of warming was +0.25K/100years in the 18th century, +1.15 K/100years in the 19th and +0.75 K/100years in the first 80 years of the 20th. Finally, the mean rate of temperature warming increased in final decades of 20th century. An analysis of linear regression coefficients in running intervals of 11, 21 and 31 years, shows that there were periods of warming with almost the same rates in the past, including the 19th century.

scholarly journals Climate reconstruction since the Little Ice Age by modelling Koryto glacier, Kamchatka Peninsula, Russia

2008 ◽  
Vol 54 (184) ◽  
pp. 125-130 ◽  
Author(s):  
Satoru Yamaguchi ◽  
Renji Naruse ◽  
Takayuki Shiraiwa
Keyword(s):  
20Th Century ◽  
Meteorological Data ◽  
Ice Core ◽  
Kamchatka Peninsula ◽  
Winter Precipitation ◽  
Ice Age ◽  
Equilibrium Line Altitude ◽  
Ice Cap ◽  
Glacier Terminus ◽  
Tree Ring Data

AbstractBased on the field data at Koryto glacier, Kamchatka Peninsula, Russia, we constructed a one-dimensional numerical glacier model which fits the behaviour of the glacier. The analysis of meteorological data from the nearby station suggests that the recent rapid retreat of the glacier since the mid-20th century is likely to be due to a decrease in winter precipitation. Using the geographical data of the glacier terminus variations from 1711 to 1930, we reconstructed the fluctuation in the equilibrium-line altitude by means of the glacier model. With summer temperatures inferred from tree-ring data, the model suggests that the winter precipitation from the mid-19th to the early 20th century was about 10% less than that at present. This trend is close to consistent with ice-core results from the nearby ice cap in the central Kamchatka Peninsula.

scholarly journals Methodological and physical biases in global to subcontinental borehole temperature reconstructions: an assessment from a pseudo-proxy perspective

2020 ◽  
Vol 16 (2) ◽  
pp. 453-474
Author(s):  
Camilo Melo-Aguilar ◽  
J. Fidel González-Rouco ◽  
Elena García-Bustamante ◽  
Norman Steinert ◽  
Johann H. Jungclaus ◽  
...  
Keyword(s):  
Surface Temperature ◽  
20Th Century ◽  
Temperature Increase ◽  
Spatial Scales ◽  
Ground Surface ◽  
Reconstruction Technique ◽  
Last Millennium ◽  
Lulc Changes ◽  
The Past ◽  
Borehole Temperature

Abstract. Borehole-based reconstruction is a well-established technique to recover information of the past climate variability based on two main hypotheses: (1) past ground surface temperature (GST) histories can be recovered from borehole temperature profiles (BTPs); (2) the past GST evolution is coupled to surface air temperature (SAT) changes, and thus, past SAT changes can be recovered from BTPs. Compared to some of the last millennium (LM) proxy-based reconstructions, previous studies based on the borehole technique indicate a larger temperature increase during the last few centuries. The nature of these differences has fostered the assessment of this reconstruction technique in search of potential causes of bias. Here, we expand previous works to explore potential methodological and physical biases using pseudo-proxy experiments with the Community Earth System Model Last Millennium Ensemble (CESM-LME). A heat-conduction forward model driven by simulated surface temperature is used to generate synthetic BTPs that are then inverted using singular value decomposition. This procedure is applied to the set of simulations that incorporates all of the LM external forcing factors as well as those that consider the concentration of the green house gases (GHGs) and the land use land cover (LULC) changes forcings separately. The results indicate that methodological issues may impact the representation of the simulated GST at different spatial scales, with the temporal logging of the BTPs as the main sampling issue that may lead to an underestimation of the simulated GST 20th-century trends. Our analysis also shows that in the surrogate reality of the CESM-LME the GST does not fully capture the SAT warming during the industrial period, and thus, there may be a further underestimation of the past SAT changes due to physical processes. Globally, this effect is mainly influenced by the GHG forcing, whereas regionally, LULC changes and other forcings factors also contribute. These findings suggest that despite the larger temperature increase suggested by the borehole estimations during the last few centuries of the LM relative to some other proxy reconstructions, both the methodological and physical biases would result in a underestimation of the 20th-century warming.

Popular Literacy and the Roots of the New Writing

1986 ◽  
Vol 168 (2) ◽  
pp. 31-46 ◽  
Author(s):  
John Willinsky
Keyword(s):  
United States ◽  
20Th Century ◽  
18Th Century ◽  
Writing Programs ◽  
The Past ◽  
New Approaches ◽  
Literacy Crisis ◽  
History Of ◽  
Popular Literacy ◽  
20Th Century United States

The place of writing in the curriculum has recently increased in importance under a series of new approaches based on a processing model of how writers write. An overlooked aspect of these new programs in the schools is the degree to which they parallel aspects of an earlier, popular literacy. In a brief recounting of incidents in the history of literacy with a focus on Renaissance Europe, 17th- and 18th-century England, and the 20th-century United States, three historical elements are brought to light which now play a strong part in the new programs. In these programs literacy (a) is sociable, (b) has its roots in nonstandardized language, and (c) places a premium on performance and publication. Insofar as the new writing takes up these aspects of popular literacy, there is reason to feel that it will work to some degree in meeting the current literacy crisis. However, the traditions of popular literacy have both political and social ramifications which warrant our attention. Popular literacy in the past has been entangled in the sensational and subversive and has not always been well received. This history raises questions as to what can be expected and what is desired of this new thrust in writing. The advocates of the new writing programs need to confront the potential of this increased voice, this latest form of popular literacy, which they have begun to encourage.

scholarly journals Kalendarze z kolekcji Ignacego Wolskiego w zbiorach Muzeum Narodowego w Krakowie

2019 ◽  
Vol 13 ◽  
pp. 223-255
Author(s):  
Agnieszka Lubera
Keyword(s):  
20Th Century ◽  
18Th Century ◽  
Future Generations ◽  
Early 20Th Century ◽  
National Museum ◽  
The Past ◽  
First Time

A small but valuable collection of calendars was donated to the National Museum in Krakow in 1896, 1898 and 1906 by Ignacy Wolski, a Warsaw bibliophile. In the article an overview of these publications is given for the first time. The donation consists of calendars diverse in form and content, published from the end of the 18th century to the early 20th century. Only ten of them were found during the research in the Museum. Most of the preserved calendars was marked with characteristic provenance stamps or stickers;a part of them has some historical notes written by Wolski. They are a great testimony of the past. Wolski’s motifs and idea behind collecting calendars and leaving these publications for future generations in the Museum were also presented in the article.

scholarly journals Late Pleistocene–Holocene ground surface heat flux changes reconstructed from borehole temperature data (the Urals, Russia)

2015 ◽  
Vol 11 (4) ◽  
pp. 647-652 ◽  
Author(s):  
D. Y. Demezhko ◽  
A. A. Gornostaeva
Keyword(s):  
Heat Flux ◽  
Surface Heat Flux ◽  
Ground Surface ◽  
Surface Heat ◽  
Middle Urals ◽  
The Urals ◽  
The Past ◽  
Carbon Dioxide Concentrations ◽  
Insolation Change ◽  
Borehole Temperature

Abstract. We use geothermal reconstruction of the ground surface temperature (GST) history early obtained in the Middle Urals to determine the surface heat flux (SHF) history over the past 35 kyr. A new algorithm of GST–SHF transformation was applied to solve this problem. The timescale of geothermal reconstructions has been corrected by comparing the estimated heat flux and annual insolation at the latitude of 60° N. The consistency of SHF and insolation changes on the interval 35–6 kyr BP with the linear correlation coefficient R = 0.99 points to orbital factors as the main cause of climatic changes during the Pleistocene–Holocene transition. The amplitude of SHF variations is about 1.3% of the insolation change amplitude. The increase of carbon dioxide concentrations lagged by 2–3 kyr from the SHF increase and occurred synchronously with GST changes.

scholarly journals Climate trends in northern Ontario and Québec from borehole temperature profiles

2016 ◽  
Vol 12 (12) ◽  
pp. 2215-2227 ◽  
Author(s):  
Carolyne Pickler ◽  
Hugo Beltrami ◽  
Jean-Claude Mareschal
Keyword(s):  
Surface Temperature ◽  
Ground Surface ◽  
Ice Age ◽  
Climate Trends ◽  
James Bay ◽  
Northern Ontario ◽  
Ground Surface Temperature ◽  
Cooling Period ◽  
The Past ◽  
Discontinuous Permafrost

Abstract. The ground surface temperature histories of the past 500 years were reconstructed at 10 sites containing 18 boreholes in northeastern Canada. The boreholes, between 400 and 800 m deep, are located north of 51° N and west and east of James Bay in northern Ontario and Québec. We find that both sides of James Bay have experienced similar ground surface temperature histories with a warming of 1.51 ± 0.76 K during the period of 1850 to 2000, similar to borehole reconstructions for the southern portion of the Superior Province and in agreement with available proxy data. A cooling period corresponding to the Little Ice Age was found at only one site. Despite permafrost maps locating the sites in a region of discontinuous permafrost, the ground surface temperature histories suggest that the potential for permafrost was minimal to absent over the past 500 years. This could be the result of air surface temperature interpolation used in permafrost models being unsuitable to account for the spatial variability of ground temperatures along with an offset between ground and air surface temperatures due to the snow cover.

scholarly journals Winter temperature variations over middle and lower reaches of the Yangtze River during the past three centuries

2012 ◽  
Vol 8 (1) ◽  
pp. 103-119
Author(s):  
Z.-X. Hao ◽  
J.-Y. Zheng ◽  
Q.-S. Ge ◽  
W.-C. Wang
Keyword(s):  
Yangtze River ◽  
18Th Century ◽  
Temperature Series ◽  
Winter Temperature ◽  
The Yangtze River ◽  
Temperature Variations ◽  
The Past ◽  
Mean Temperature ◽  
The Mean ◽  
The 19Th Century

Abstract. We present statistically reconstructed annual winter (December–February) mean temperature in the Middle and Lower Reaches of the Yangtze River (24–34° N, east of 108° E) back to 1736. The reconstructions are based on information from snowfall days from Yu-Xue-Fen-Cun archive (one of historical documents proxies) in Qing Dynasty (1644–1911). Those information are calibrated with regional winter temperature series spanning the period 1951 to 2007 period. The gap from 1912 to 1950 is filled using early instrumental observation. With respect to the 1951–2007 climatology, the 18th century was 0.6 °C colder, and the 19th century was 1.0 °C colder. But since the 20th century, climate entered into the warming phase, particular in the last 30 yr, the mean temperature from 1981 to 2007 is 0.25 °C higher than that of climatology, a highest level of the past 300 yr. The uncertainty is existed for the period prior of 1900, and possible causes have been discussed here.

scholarly journals Higher-than-present Medieval pine (Pinus sylvestris) treeline along the Swedish Scandes

2015 ◽  
Vol 42 ◽  
pp. 1-14 ◽  
Author(s):  
Leif Kullman
Keyword(s):  
Pinus Sylvestris ◽  
Ground Surface ◽  
Ice Age ◽  
Lapse Rate ◽  
Medieval Period ◽  
Climate Change And Variability ◽  
The Past ◽  
Northern Fennoscandia ◽  
Detection And Attribution ◽  
Summer Temperatures

The upper treeline of Scots pine (Pinus sylvestris L.) is renowned as a sensitive indicator of climate change and variability. By use of megafossil tree remains, preserved exposed on the ground surface, treeline shift over the past millennium was investigated at multiple sites along the Scandes in northern Sweden. Difference in thermal level between the present and the Medieval period, about AD 1000-1200, is a central, although controversial, aspect concerning the detection and attribution of anthropogenic climate warming. Radiocarbon-dated megafossil pines revealed that the treeline was consistently positioned as much as 115 m higher during the Medieval period than today (AD 2000-2010), after a century of warming and substantial treeline upshift. Drawing on the last-mentioned figure, and a lapse rate of 0.6oC/100 m, it may be inferred that Medieval summer temperatures were about 0.7 oC warmer than much of the past 100 years. Extensive pine mortality and treeline descent after the Medieval warming peak reflect substantially depressed temperatures during the Little Ice Age. Warmer-than-present conditions during the Medieval period concur with temperature reconstructions from different parts of northern Fennoscandia, northwestern Russia and Greenland. Modern warming has not been sufficient to restore Medieval treelines. Against this background, there is little reason to view further modest warming as unnatural.

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