Tropical Pacific – mid-latitude teleconnections in medieval times     

Nicholas E. Graham  Malcolm K. Hughes  Caspar M. Ammann  Kim M. Cobb  Martin P. Hoerling  Douglas J. Kennett  James P. Kennett  Bert Rein  Lowell Stott  Peter E. Wigand  Taiyi Xu 《Climatic change》2007,83(1-2):241-285

Terrestrial and marine late Holocene proxy records from the western and central US suggest that climate between approximately 500 and 1350 a.d. was marked by generally arid conditions with episodes of severe centennial-scale drought, elevated incidence of wild fire, cool sea surface temperatures (SSTs) along the California coast, and dune mobilization in the western plains. This Medieval Climate Anomaly (MCA) was followed by wetter conditions and warming coastal SSTs during the transition into the “Little Ice Age” (LIA). Proxy records from the tropical Pacific Ocean show contemporaneous changes indicating cool central and eastern tropical Pacific SSTs during the MCA, with warmer than modern temperatures in the western equatorial Pacific. This pattern of mid-latitude and tropical climate conditions is consistent with the hypothesis that the dry MCA in the western US resulted (at least in part) from tropically forced changes in winter NH circulation patterns like those associated with modern La Niña episodes. We examine this hypothesis, and present other analyses showing that the imprint of MCA climate change appears in proxy records from widely distributed regions around the planet, and in many cases is consistent with a cool medieval tropical Pacific. One example, explored with numerical model results, is the suggestion of increased westerlies and warmer winter temperatures over northern Europe during medieval times. An analog technique for the combined use of proxy records and model results, Proxy Surrogate Reconstruction (PSR), is introduced.  相似文献   

75 Jahre von univ. prof. Dr. Mikuláš Konček,DrSc     

František Rein 《Studia Geophysica et Geodaetica》1975,19(4):405-405

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Holocene Climate Variability in Antarctica Based on 11 Ice-Core Isotopic Records   总被引：1，自引：0，他引：1  

Valrie Masson  Franoise Vimeux  Jean Jouzel  Vin Morgan  Marc Delmotte  Philippe Ciais  Claus Hammer  Sigfus Johnsen  Vladimir Ya. Lipenkov  E. Mosley-Thompson  Jean-Robert Petit  Eric J. Steig  Michel Stievenard  Rein Vaikmae 《Quaternary Research》2000,54(3):348

A comparison is made of the Holocene records obtained from water isotope measurements along 11 ice cores from coastal and central sites in east Antarctica (Vostok, Dome B, Plateau Remote, Komsomolskaia, Dome C, Taylor Dome, Dominion Range, D47, KM105, and Law Dome) and west Antarctica (Byrd), with temporal resolution from 20 to 50 yr. The long-term trends possibly reflect local ice sheet elevation fluctuations superimposed on common climatic fluctuations. All the records confirm the widespread Antarctic early Holocene optimum between 11,500 and 9000 yr; in the Ross Sea sector, a secondary optimum is identified between 7000 and 5000 yr, whereas all eastern Antarctic sites show a late optimum between 6000 and 3000 yr. Superimposed on the long time trend, all the records exhibit 9 aperiodic millennial-scale oscillations. Climatic optima show a reduced pacing between warm events (typically 800 yr), whereas cooler periods are associated with less-frequent warm events (pacing >1200 yr).  相似文献   

Geographies of mobility: applications of location-based data     

Matthew Zook  Rein Ahas 《International journal of geographical information science》2015,29(11):1935-1940

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Stable models of elliptical galaxies   总被引：1，自引：0，他引：1  

G. Rein  Y. Guo 《Monthly notices of the Royal Astronomical Society》2003,344(4):1296-1306

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Future changes in internal variability of the Atlantic Meridional Overturning Circulation     

Sybren Drijfhout  Wilco Hazeleger  Frank Selten  Rein Haarsma 《Climate Dynamics》2008,30(4):407-419

The response of the internal variability of the Atlantic Meridional Overturning Circulation (MOC) to enhanced atmospheric greenhouse gas concentrations has been estimated from an ensemble of climate change scenario runs. In the model, enhanced greenhouse forcing results in a weaker and shallower MOC with reduced internal variability. At the same time at 55°N between 0 and 1,000 m the overturning increases as a result of a change in the area of convection. In a warmer world, new regions of deepwater formation form further north due to the poleward retreat of the sea-ice boundary. The dominant pattern of internal MOC-variability consists of a monopole centered around 35°N. Due to anthropogenic warming this monopole shifts poleward. The shift is associated with a stronger relation between MOC-variations and heat flux variations over the subpolar gyre. In old convective sites (Labrador Sea) convection becomes more irregular which leads to enhanced heat flux variability. In new convective sites heat flux variations initially are related to sea-ice variations. When the sea-ice coverage further decreases they become associated with (irregular) deepwater formation. Both processes act to tighten the relation between subpolar surface heat flux variability and MOC-variability, resulting in a poleward shift of the latter.  相似文献   

Comparison of Phytoscreening and Direct‐Push‐Based Site Investigation at a Rural Megasite Contaminated with Chlorinated Ethenes          下载免费PDF全文

Arno Rein  Olaf Holm  Stefan Trapp  Steffen Popp‐Hofmann  Martin Bittens  Carsten Leven  Peter Dietrich 《Ground Water Monitoring & Remediation》2015,35(4):45-56

The reliable characterization of subsurface contamination of spatially extended contaminated sites is a challenging task, especially with an unknown history of land use. Conventional technologies often fail due to temporal and financial constraints and thus hinder the redevelopment of abandoned areas in particular. Here we compare two site screening techniques that can be applied quickly at relatively low cost, namely Direct Push (DP)‐based groundwater sampling and tree core sampling. The effectiveness of both methods is compared for a rural megasite contaminated with chlorinated hydrocarbons. Unexpected pollution hot spots could be identified using both of these methods, while tree coring even enabled the delineation of the contaminant plume flowing into an adjacent wetland inaccessible for DP units. Both methods showed a good agreement in revealing the spatial pattern of the contamination. The correlation between groundwater concentrations and equivalent concentrations in wood was linear and highly significant for trichloroethene. Correlation was less obvious for its metabolite cis‐dichloroethene, but still significant. As outcome of our study we recommend tree coring and for initial screening in combination with a DP sampling to retrieve quantitative data on groundwater pollutants in order to assess the contamination situation of a non‐ or only partly investigated site. The subsequent placement of monitoring wells for long‐term monitoring of contamination levels is recommended. A combination of methods would achieve more relevant information at comparable or possibly even lower efforts in comparison to a conventional site investigation.  相似文献   

Ausgeglichene Isohypsen Mitteleuropas     

František Rein 《Studia Geophysica et Geodaetica》1960,4(1):96-98

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The problem of temperature trends and winter seasons 1950–1977 at the observatories in Prague-Klementinum and at Milešovka     

Jaroslava Kalvová  Reviewer F. Rein 《Studia Geophysica et Geodaetica》1980,24(2):201-207

Summary The winter seasons of 1950|51–1975|76 at the observatories of Mileovka and Prague-Klementinum were analysed from the point of view of the existence of a temperature trend. The investigated period is characterized by a non-uniform distribution of warm and cold events and a high interannual variability. Regression lines fitted to the interval 1950|51–1962|63 display a negative slope, however, randomness tests do not prove the existence of a temperature trend. The interval 1962|63–1975|76 was a period of temperature increase. The sets of winter temperatures are characterized by a high level of climatic noise.  相似文献   

In-situ reflectance spectroscopy – analysing techniques for high-resolution pigment logging in sediment cores     

Bert Rein  Frank Sirocko 《International Journal of Earth Sciences》2003,92(1):143-143

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