@misc{BiermannSchwarzDiazSolaretal.2001,
  author    = {Biermann, Kurt-Reinhard and Schwarz, Ingo and D{\´i}az Solar, Francisco and D{\´i}az Infante, Duanel and Ette, Ottmar and Faak, Margot and Krumpel, Heinz and Lubrich, Oliver and Thiemer-Sachse, Ursula and Weigl, Engelhard},
  title     = {HiN : Alexander von Humboldt im Netz},
  volume    = {II},
  number    = {2},
  editor    = {Ette, Ottmar and Knobloch, Eberhard},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  issn      = {2568-3543},
  doi       = {10.25932/publishup-42419},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-424194},
  pages     = {127},
  year      = {2001},
  abstract  = {Inhalt: - Kurt-R. Biermann und Ingo Schwarz: Der Aachener Kongreß und das Scheitern der indischen Reisepl{\"a}ne Alexander von Humboldts - Kurt-R. Biermann und Ingo Schwarz: „Sibirien beginnt in der Hasenheide" - Alexander von Humboldts Neigung zur Moquerie - Kurt-R. Biermann und Ingo Schwarz: Rezepte des jungen Alexander von Humboldt von 1789 gegen Mangel an Arbeit und an Subsistenz - Francisco D{\´i}az Solar y Duanel D{\´i}az Infante: Gast{\´o}n Baquero invita a leer Cosmos, de Alejandro de Humboldt - Ottmar Ette: The Scientist as Weltb{\"u}rger: Alexander von Humboldt and the Beginning of Cosmopolitics - Margot Faak: Alexander von Humboldt. Reise durch Venezuela - Heinz Krumpel: Zur Aneignung und Verwandlung der Ideen Humboldts und Krauses in Lateinamerika - Gemeinsamkeiten und Unterschiede - Oliver Lubrich: En el reino de la ambivalencia. La Cuba de Alejandro de Humboldt - Ursula Thiemer-Sachse: Welche Kunst es ist, Kunst zu begreifen … Alexander von Humboldts Sicht auf indianische Kunst - Engelhard Weigl: Alexander von Humboldt and the Beginning of the Environmental Movement},
  language  = {de}
}
@misc{BiermannEtteKnoblochetal.2004,
  author    = {Biermann, Kurt-Reinhard and Ette, Ottmar and Knobloch, Eberhard and Lindquist, Jason H. and Lubrich, Oliver and Weigl, Engelhard},
  title     = {HiN : Alexander von Humboldt im Netz},
  volume    = {V},
  number    = {9},
  editor    = {Ette, Ottmar and Knobloch, Eberhard},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  issn      = {1617-5239},
  doi       = {10.18443/hinvol5iss092004},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-35157},
  pages     = {92},
  year      = {2004},
  abstract  = {- Kurt-R. Biermann (hg. von I. Schwarz): Ein „politisch schiefer Kopf" und der „letzte Mumienkasten" - Humboldt und Metternich - Ottmar Ette: Die Ordnung der Weltkulturen : Alexander von Humboldts Ansichten der Kultur - Eberhard Knobloch: Naturgenuss und Weltgem{\"a}lde : Gedanken zu Humboldts Kosmos - Jason H. Lindquist: threats to the European subject in Humboldt's personal narrative of travels to the equinoctial regions of the New Continent - Oliver Lubrich: Sobre la disoluci{\´o}n del clasicismo en la Relaci{\´o}n hist{\´o}rica de un viaje a las regiones equinocciales del Nuevo Continente - Engelhard Weigl: Wald und Klima: Ein Mythos aus dem 19. Jahrhundert},
  language  = {de}
}
@article{Weigl2004,
  author    = {Weigl, Engelhard},
  title     = {Wald und Klima},
  series = {HIN : Alexander von Humboldt im Netz ; international review for Humboldtian studies},
  volume    = {V},
  journal   = {HIN : Alexander von Humboldt im Netz ; international review for Humboldtian studies},
  number    = {9},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  issn      = {2568-3543},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-35123},
  pages     = {74 -- 92},
  year      = {2004},
  abstract  = {Fr{\"u}h setzte in Europa die Wahrnehmung der Ver{\"a}nderung des regionalen Klimas durch Waldrodungen ein. Als erster widmete Theophrastus (372-288 v. Chr.) dem Thema des menschlichen Einflusses auf die Temperatur und die Qualit{\"a}t der Luft einer Region ausf{\"u}hrliche {\"U}berlegungen. Mit ihm beginnt ein Diskurs, der durch die Entdeckung und Kolonisierung Amerikas einen enormen Aufschwung erfuhr und im letzten Drittel des 19. Jahrhunderts auf globaler Ebene seinen H{\"o}hepunkt erreichte, um dann nach der Jahrhundertwende in Vergessenheit zu geraten. Alexander von Humboldt legte in seinem Amerika-Werk durch seine Fallstudie zum See von Valencia (1799) die ersten wissenschaftlichen Grundlagen f{\"u}r die systematische Untersuchung der Frage nach dem durch Menschen verursachten Ver{\"a}nderungen des Klimas. Die Fortsetzung dieser Studien in Lateinamerika durch Jean Baptist Boussingault erregten weltweites Aufsehen und wurden f{\"u}r die fr{\"u}he Umweltbewegung (George Marsh) zum zentralen Argument bei der Verteidigung der W{\"a}lder in Europa, in den U.S.A. und in den Kolonien. Dem Klimaeinfluss des Waldes wuchs immer mehr eine mythische Gr{\"o}sse zu, sodass bei der Erschliessung regenarmer Regionen (in Australien und in den U.S.A.) umfangreiche Aufforstungsprogramme die Niederschlagsmenge erh{\"o}hen sollten. Nach dem Scheitern dieser Programme war generell die Bef{\"u}rchtung erwarteter anthropogener Klimakatastrophen durch die Zerst{\"o}rung der W{\"a}lder diskreditiert.},
  language  = {de}
}
@article{Weigl2001,
  author    = {Weigl, Engelhard},
  title     = {Alexander von Humboldt and the beginning of the environmental movement},
  series = {HiN : Alexander von Humboldt im Netz ; International Review for Humboldtian Studies},
  volume    = {II},
  journal   = {HiN : Alexander von Humboldt im Netz ; International Review for Humboldtian Studies},
  number    = {2},
  publisher = {Universit{\"a}tsverlag Potsdam},
  address   = {Potsdam},
  doi       = {10.18443/15},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-34595},
  pages     = {121 -- 127},
  year      = {2001},
  abstract  = {In the middle of the 19th century the question whether expanding civilization and industrialization had an effect on climate was discussed intensely worldwide. It was feared that increasing deforestation would lead to continuous decrease in rainfall. This first scientific discussion about climate change as the result of human intervention was strongly influenced by the research Alexander von Humboldt and Jean-Baptiste Boussingault had undertaken when they investigated the falling water levels of Lake Valencia in Venezuela. This essay aims to clarify the question whether Alexander von Humboldt can be counted among the leading figures of modern environmentalism on account of this research as is being claimed by Richard H. Grove in his influential book Green Imperialism. Colonial Expansion, Tropical Island Edens and Origins of Environmentalism, 1600-1860 (1995).},
  language  = {en}
}
@phdthesis{Sorrel2006,
  author    = {Sorrel, Philippe},
  title     = {The Aral Sea : a palaeoclimate archive},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-7807},
  school      = {Universit{\"a}t Potsdam},
  year      = {2006},
  abstract  = {The intracontinental endorheic Aral Sea, remote from oceanic influences, represents an excellent sedimentary archive in Central Asia that can be used for high-resolution palaeoclimate studies. We performed palynological, microfacies and geochemical analyses on sediment cores retrieved from Chernyshov Bay, in the NW part of the modern Large Aral Sea. The most complete sedimentary sequence, whose total length is 11 m, covers approximately the past 2000 years of the late Holocene. High-resolution palynological analyses, conducted on both dinoflagellate cysts assemblages and pollen grains, evidenced prominent environmental change in the Aral Sea and in the catchment area. The diversity and the distribution of dinoflagellate cysts within the assemblages characterized the sequence of salinity and lake-level changes during the past 2000 years. Due to the strong dependence of the Aral Sea hydrology to inputs from its tributaries, the lake levels are ultimately linked to fluctuations in meltwater discharges during spring. As the amplitude of glacial meltwater inputs is largely controlled by temperature variations in the Tien Shan and Pamir Mountains during the melting season, salinity and lake-level changes of the Aral Sea reflect temperature fluctuations in the high catchment area during the past 2000 years. Dinoflagellate cyst assemblages document lake lowstands and hypersaline conditions during ca. 0-425 AD, 920-1230 AD, 1500 AD, 1600-1650 AD, 1800 AD and since the 1960s, whereas oligosaline conditions and higher lake levels prevailed during the intervening periods. Besides, reworked dinoflagellate cysts from Palaeogene and Neogene deposits happened to be a valuable proxy for extreme sheet-wash events, when precipitation is enhanced over the Aral Sea Basin as during 1230-1450 AD. We propose that the recorded environmental changes are related primarily to climate, but may have been possibly amplified during extreme conditions by human-controlled irrigation activities or military conflicts. Additionally, salinity levels and variations in solar activity show striking similarities over the past millennium, as during 1000-1300 AD, 1450-1550 and 1600-1700 AD when low lake levels match well with an increase in solar activity thus suggesting that an increase in the net radiative forcing reinforced past Aral Sea's regressions. On the other hand, we used pollen analyses to quantify changes in moisture conditions in the Aral Sea Basin. High-resolution reconstruction of precipitation (mean annual) and temperature (mean annual, coldest versus warmest month) parameters are performed using the "probability mutual climatic spheres" method, providing the sequence of climate change for the past 2000 years in western Central Asia. Cold and arid conditions prevailed during ca. 0-400 AD, 900-1150 AD and 1500-1650 AD with the extension of xeric vegetation dominated by steppe elements. Conversely, warmer and less arid conditions occurred during ca. 400-900 AD and 1150-1450 AD, where steppe vegetation was enriched in plants requiring moister conditions. Change in the precipitation pattern over the Aral Sea Basin is shown to be predominantly controlled by the Eastern Mediterranean (EM) cyclonic system, which provides humidity to the Middle East and western Central Asia during winter and early spring. As the EM is significantly regulated by pressure modulations of the North Atlantic Oscillation (NAO) when the system is in a negative phase, a relationship between humidity over western Central Asia and the NAO is proposed. Besides, laminated sediments record shifts in sedimentary processes during the late Holocene that reflect pronounced changes in taphonomic dynamics. In Central Asia, the frequency of dust storms occurring during spring when the continent is heating up is mostly controlled by the intensity and the position of the Siberian High (SH) Pressure System. Using titanium (Ti) content in laminated sediments as a proxy for aeolian detrital inputs, changes in wind dynamics over Central Asia is documented for the past 1500 years, offering the longest reconstruction of SH variability to date. Based on high Ti content, stronger wind dynamics are reported from 450-700 AD, 1210-1265 AD, 1350-1750 AD and 1800-1975 AD, reporting a stronger SH during spring. In contrast, lower Ti content from 1750-1800 AD and 1980-1985 AD reflect a diminished influence of the SH and a reduced atmospheric circulation. During 1180-1210 AD and 1265-1310 AD, considerably weakened atmospheric circulation is evidenced. As a whole, though climate dynamics controlled environmental changes and ultimately modulated changes in the western Central Asia's climate system, it is likely that changes in solar activity also had an impact by influencing to some extent the Aral Sea's hydrology balance and also regional temperature patterns in the past. <hr> The appendix of the thesis is provided via the HTML document as ZIP download.},
  subject      = {Aralsee},
  language  = {en}
}