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[Music throughout]

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Global temperatures are on the rise.

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As our climate changes,

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Earth is seeing more extreme and unusual weather.

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In 2019, the National Audubon Society reported

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that two-thirds of America’s birds are threatened by climate change.

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That’s 389 species in danger of extinction.

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Scientists at the University of Wisconsin-Madison

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are trying to figure out how temperature affects

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bird biodiversity across the country,

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which will help conservationists figure out

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where to prioritize their efforts.

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The team used data from Landsat’s thermal sensor,

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called TIRS,

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to map temperature across the United States.

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They also used a computer algorithm to map small-scale temperature differences.

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For example, a grove of trees in an open field.

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The algorithm compares the temperature variability in one area

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to those adjacent to it.

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The team then compared their temperature data

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to bird biodiversity across the country,

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focusing on the winter months

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and birds that don’t migrate to find warmer temperatures.

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Turns out, large-bodied bird species

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tend to choose places with higher overall temperatures.

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But for small birds and climate-threatened species,

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having a habitat with variable temperatures seems to be more important.

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The researchers speculate that some birds may use pockets of warmer habitat –

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like a nest, a snow burrow, or a patch of dense tree cover –

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to wait out a cold spell or weather event.

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In the study, temperature explained about a third of why some areas

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have more bird species than others.

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But that still leaves nearly two-thirds unaccounted for.

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To protect many bird species from extinction,

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scientists will have to find other factors affecting bird biodiversity.