Historical upper treeline (front) and actual treeline (back) in the Polar Ural, Russia.
Source: Jan Esper
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Fossil trunk in a river bed, Yamal, Russia.
Source: Lukas Fellmann
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In situ fossile stump at the upper treeline in the Polar Ural, Russia.
Source: Jan Esper
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Another fossile stump in the Polar Ural, Russia.
Source: Jan Esper
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Northernmost treeline (>72°N) in Taimyr, Siberia, Russia.
Source: Lukas Fellmann
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Treeline in the Putorana Mountains, Siberia, Russia.
Source: Lukas Fellmann
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Pure walnut forest on loess, central Kirghizia.
Source: Jan Esper
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Loess erosion, central Kirghizia.
Source: Jan Esper
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Inner-mountainous circulations system typical for the Karakorum, Pakistan.
Source: Jan Esper
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Betula/Juniperus timberline in 4,000 m a.s.l., Karakorum, Pakistan.
Source: Jan Esper
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Aspect and vegetation. North-facing slope with a mixed Juniperus, Pinus, Picea forest in the Bagrot valley, Karakorum, Pakistan.
Source: Jan Esper
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Glacier and side-moraine, Karakorum, Pakistan.
Source: Thomas Reineke
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Irrigated agricultural area, Karakorum, Pakistan.
Source: Jan Esper
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Avalanche, Loetschental, Switzerland.
Source: Jan Esper
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Avalanche and injury, Loetschental, Switzerland.
Source: Jan Esper
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Map including High Asia.
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1000-yr old Juniperus turkestanica tree in about 4,000 m a.s.l., Karakorum, Pakistan.
Source: Jan Esper
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Uncovered root system of a juniper tree, Karakorum, Pakistan.
Source: Jan Esper
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Typical star-shaped cross section including strip bark formation of an old juniper tree, Karakorum, Pakistan.
Source: Jan Esper
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Reaction wood on a Pinus cembra cross section from the upper timberline, Engadin, Switzerland.
Source: Jan Esper
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Cross section of a Larix decidua root including a change in wood formation caused by exposure.
Source: Holger Gärtner
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Core samples.
Source: Jan Esper
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Abrupt growth release on a Larix sibirica cross section from the Anabarskoe plateau, Siberia, Russia.
Source: Jan Esper
(high res jpg) Ref.: Esper et al., GRL (2004).

700-yr old historic building ("Stadel") in Ferden, Lötschental, Switzerland.
Source: Ulf Büntgen
(high res jpg) Ref.: Büntgen et al., Erdkunde (in review).

Core sampling.
Source: Jan Esper
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Core sampling.
Source: Jan Esper
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Core sampling.
Source: Jan Esper
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Core sampling.
Source: Jan Esper
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Core sampling.
Source: Jan Esper
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Sampling heights for treeline studies.
Source: Jan Esper
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Sampling a large Cedrus atlantica tree in the Middle Atlas, Morocco.
Source: Jan Esper
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Cedrus atlantica, Middle Atlas, Morocco.
Source: Jan Esper
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Dead Cedrus atlantica forest in the Middle Atlas, Morocco. Trees were pollarded to feed animals.
Source: Jan Esper
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Another dead Cedar forest.
Source: Daniel Nievergelt
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Cedrus atlantica.
Source: Jan Esper
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25 m long root of a Cedrus atlantica tree.
Source: Jan Esper
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The long root again.
Source: Daniel Nievergelt
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Wedging ring, Juniperus spec.
Source: Jan Esper
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Density variation, Juniperus spec.
Source: Jan Esper
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Callus tissue caused by frost, Juniperus spec.
Source: Jan Esper
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Negative pointer year (narrow ring), Juniperus spec.
Source: Jan Esper
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Compression wood, Juniperus spec.
Source: Jan Esper
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Diagonal growth, Juniperus spec.
Source: Jan Esper
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Meteorological station in about 3,800 m a.s.l., Karakorum, Pakistan.
Source: Jan Esper
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Meteorological station, Tien Shan, Kirghizia.
Source: Jan Esper
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Juniper forests in the Karagui valley, Tien Shan, Kirghizia.
Source: Jan Esper
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Block glacier, Tien Shan, Kirghizia.
Source: Jan Esper
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Twisted juniper trees, Tien Shan, Kirghizia.
Source: Jan Esper
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Fieldwork fun, Tien Shan, Kirghizia.
Source: Jan Esper
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Fieldwork fun, Tien Shan, Kirghizia.
Source: Jan Esper
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Ph.D. students.
Source: Jan Esper
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Morning impression Rakaposhi Mt., Karakorum, Pakistan.
Source: Jan Esper
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