@article{GuntherZhukBezerraetal.2005,
  author    = {Gunther, U. and Zhuk, Alexandre and Bezerra, Valdir B. and Romero, C.},
  title     = {AdS and stabilized extra dimensions in multi-dimensional gravitational models with nonlinear scalar curvature terms R-1 and R-4},
  issn      = {0264-9381},
  year      = {2005},
  abstract  = {We study multi-dimensional gravitational models with scalar curvature nonlinearities of types R-1 and R-4. It is assumed that the corresponding higher dimensional spacetime manifolds undergo a spontaneous compactification to manifolds with a warped product structure. Special attention has been paid to the stability of the extra-dimensional factor spaces. It is shown that for certain parameter regions the systems allow for a freezing stabilization of these spaces. In particular, we find for the R-1 model that configurations with stabilized extra dimensions do not provide a late-time Acceleration (they are AdS), whereas the solution branch which allows. for accelerated expansion (the dS branch) is incompatible with stabilized factor spaces. In the case of the R-4 model, we obtain that the stability region in parameter space depends on the total dimension D = dim(M) of the higher dimensional spacetime M. Tor D > 8 the stability region consists of a single (absolutely stable) sector which is shielded from a conformal singularity (and an antigravity sector beyond it) by a potential barrier of infinite height and width. This sector is smoothly connected with the stability region of a curvature-linear model. For D < 8 an additional (metastable) sector exists Which is separated from the conformal singularity by a potential barrier of finite height and width so that systems in this sector are prone to collapse into the conformal singularity. This second sector is not smoothly connected with the first (absolutely stable) one. Several limiting cases and the possibility of inflation are discussed for the R-4 model},
  language  = {en}
}
@article{AckermannWidekindFiermentetal.1999,
  author    = {Ackermann, Peter and Widekind, Justus v. and Fierment, Gerold and Lindloff, Karsten and Schneider, Lothar and G{\"u}nther, B. and M{\"u}ller, O. and Jischa, M.-F.},
  title     = {Konzepte und Instrumentarien f{\"u}r die Gestaltung einer nachhaltig zukunftsvertr{\"a}glichen Entwicklung},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-4115},
  year      = {1999},
  abstract  = {Konzepte und Instrumentarien f{\"u}r die Gestaltung einer nachhaltig zukunftsvertr{\"a}glichen Entwicklung ; ACKERMANN, P.: Nachhaltige Entwicklung - ein neues gesellschaftliches Paradigma? ; WIDEKIND, J.v.: Agenda 21 - Von Rio bis Brandenburg ; FIERMENT, G.; ACKERMANN, P.: Lokale Agenda 21-Prozesse - Werkzeug f{\"u}r die lokale Gestaltung einer nachhaltig zukunftsvertr{\"a}glichen Entwicklung ; LINDLOFF, K.; SCHNEIDER, L.: Integrierte Umweltberatung - Regionale Vernetzung von Umweltakteuren und partizipatorische Entwicklung {\"o}kologischer Ziele ; G{\"U}NTHER, B.; M{\"U}LLER, E.O.: Der Runde Tisch zur nachhaltigen Entwicklung in Berlin und Brandenburg: Beispiel f{\"u}r eine lernende Organisation ; JISCHA, M.F.: Das Leitbild Nachhaltigkeit und das Konzept Technikbewertung},
  language  = {de}
}
@article{WetterichSchirrmeisteNazarovaetal.2018,
  author    = {Wetterich, Sebastian and Schirrmeiste, Lutz and Nazarova, Larisa B. and Palagushkina, Olga and Bobrov, Anatoly and Pogosyan, Lilit and Savelieva, Larisa and Syrykh, Liudmila and Matthes, Heidrun and Fritz, Michael and G{\"u}nther, Frank and Opel, Thomas and Meyer, Hanno},
  title     = {Holocene thermokarst and pingo development in the Kolyma Lowland (NE Siberia)},
  series = {Permafrost and Periglacial Processes},
  volume    = {29},
  journal   = {Permafrost and Periglacial Processes},
  number    = {3},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {1045-6740},
  doi       = {10.1002/ppp.1979},
  pages     = {182 -- 198},
  year      = {2018},
  abstract  = {Ground ice and sedimentary records of a pingo exposure reveal insights into Holocene permafrost, landscape and climate dynamics. Early to mid-Holocene thermokarst lake deposits contain rich floral and faunal paleoassemblages, which indicate lake shrinkage and decreasing summer temperatures (chironomid-based T-July) from 10.5 to 3.5 cal kyr BP with the warmest period between 10.5 and 8 cal kyr BP. Talik refreezing and pingo growth started about 3.5 cal kyr BP after disappearance of the lake. The isotopic composition of the pingo ice (delta O-18 - 17.1 +/- 0.6 parts per thousand, delta D -144.5 +/- 3.4 parts per thousand, slope 5.85, deuterium excess -7.7 +/- 1.5 parts per thousand) point to the initial stage of closed-system freezing captured in the record. A differing isotopic composition within the massive ice body was found (delta O-18 - 21.3 +/- 1.4 parts per thousand, delta D -165 +/- 11.5 parts per thousand, slope 8.13, deuterium excess 4.9 +/- 3.2 parts per thousand), probably related to the infill of dilation cracks by surface water with quasi-meteoric signature. Currently inactive syngenetic ice wedges formed in the thermokarst basin after lake drainage. The pingo preserves traces of permafrost response to climate variations in terms of ground-ice degradation (thermokarst) during the early and mid-Holocene, and aggradation (wedge-ice and pingo-ice growth) during the late Holocene.},
  language  = {en}
}
@article{OpelMurtonWetterichetal.2019,
  author    = {Opel, Thomas and Murton, Julian B. and Wetterich, Sebastian and Meyer, Hanno and Ashastina, Kseniia and G{\"u}nther, Frank and Grotheer, Hendrik and Mollenhauer, Gesine and Danilov, Petr P. and Boeskorov, Vasily and Savvinov, Grigoriy N. and Schirrmeister, Lutz},
  title     = {Past climate and continentality inferred from ice wedges at Batagay Highlands, interior Yakutia},
  series = {Climate of the past : an interactive open access journal of the European Geosciences Union},
  volume    = {15},
  journal   = {Climate of the past : an interactive open access journal of the European Geosciences Union},
  number    = {4},
  publisher = {Copernicus},
  address   = {G{\"o}ttingen},
  issn      = {1814-9324},
  doi       = {10.5194/cp-15-1443-2019},
  pages     = {1443 -- 1461},
  year      = {2019},
  abstract  = {Ice wedges in the Yana Highlands of interior Yakutia - the most continental region of the Northern Hemisphere - were investigated to elucidate changes in winter climate and continentality that have taken place since the Middle Pleistocene. The Batagay megaslump exposes ice wedges and composite wedges that were sampled from three cryostratigraphic units: the lower ice complex of likely pre-Marine Isotope Stage (MIS) 6 age, the upper ice complex (Yedoma) and the upper sand unit (both MIS 3 to 2). A terrace of the nearby Adycha River provides a Late Holocene (MIS 1) ice wedge that serves as a modern reference for interpretation. The stable-isotope composition of ice wedges in the MIS 3 upper ice complex at Batagay is more depleted (mean delta O-18 about -35 parts per thousand) than those from 17 other ice-wedge study sites across coastal and central Yakutia. This observation points to lower winter temperatures and therefore higher continentality in the Yana Highlands during MIS 3. Likewise, more depleted isotope values are found in Holocene wedge ice (mean delta O-18 about -29 parts per thousand) compared to other sites in Yakutia. Ice-wedge isotopic signatures of the lower ice complex mean delta O-18 about -33 parts per thousand) and of the MIS 3-2 upper sand unit (mean delta O-18 from about -33 parts per thousand to -30 parts per thousand) are less distinctive regionally. The latter unit preserves traces of fast formation in rapidly accumulating sand sheets and of post-depositional isotopic fractionation.},
  language  = {en}
}