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The Arctic is changing rapidly, and scientists have uncovered a powerful mix of natural and human-driven processes fueling that change. Cracks in sea ice release heat and pollutants that form clouds and speed up melting, while emissions from nearby oil fields alter the chemistry of the air. These interactions trigger feedback loops that let in more sunlight, generate smog, and push warming even further. Together, they paint a troubling picture of how fragile the Arctic system has become.