修建中国长城的工程跨越了数千年。其中最著名的部分是明朝时期建造的蜿蜒的防御工事，建于14世纪至17世纪之间。它每年吸引着上千万的游客。与之相比，已有2000年历史的汉代长城——如今看起来有点像是堆放在沙漠中布满灰尘的饼干——吸引的游客要少得多。

Multi-annual measurements across Lake Superior indicate remarkable similarities between large lakes and ocean CO2 exchange during the ice-free season.

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More than 40 square kilometers of vegetation cover Antarctica, including in previously unknown areas. A new map offers fresh insights for conservation amid climate change.

Increased temperatures and drought are leading to more wildfires. And wildfire smoke aerosols can suppress precipitation, ...

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A deep learning model trained with geophysical data recorded during the well-documented 2018 Kilauea volcano eruption, Hawaii, predicts recurrent caldera collapse events.

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Minuscule meteoroids slamming into the lunar surface could be kicking up most of the atoms that make up the lunar exosphere.