When warmer and wetter conditions returned, the birds became isolated in several islands of grass in a sea of forest.

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It's measured in a changing climate, as sea levels rise, and droughts spread, forest burns, and storms rage.

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Standing 2, 430 m above sea level, in the midst of a tropical mountain forest in an extraordinarily beautiful setting, Machu Picchu was probably the most amazing urban creation of the Inca Empire at its height.

UNESCO: MEDIA SERVICES

Natural aerosols are produced by sea salt, desert dust, volcanic eruptions and smoke from forest fires.

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Machu Picchu stands 2, 430 m above sea-level, in the middle of a tropical mountain forest, in an extraordinarily beautiful setting.

UNESCO: MEDIA SERVICES

Its location gave them refuge from the northern sea storms and access to the ship building materials found in Ireland's dense forest.

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Extensive parkland with a mosaic of forest patches and subalpine meadow communities extends from 1, 500 - 2, 000 meters above sea level.

UNESCO: Biosphere Reserve Information