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Why did dust from the Chicxulub impact make Earth colder?

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The Chicxulub asteroid — Earth impact hazard An artist's rendering of the impact of a near-Earth object 66 million years ago in what is today the Caribbean region. Many scientists think that the collision of a large asteroid or comet nucleus with Earth triggered the mass extinction of dinosaurs and many other species near the end of the Cretaceous Period.

The cooling of Earth following the Chicxulub impact was primarily caused by the injection of massive quantities of fine dust and debris into the atmosphere. This material created a global cloud that effectively blocked sunlight from reaching the surface for years or even decades.123

By preventing solar radiation from penetrating the atmosphere, this "impact winter" led to a significant drop in global temperatures, which are estimated to have fallen by as much as 28 °C (50 °F). The lack of sunlight also halted photosynthesis, which disrupted the food chain and contributed to the mass extinction of approximately 80 percent of all species, including the dinosaurs. Additionally, the impact vaporized sulfur-rich rocks, releasing several hundred gigatons of sulfur into the atmosphere, which formed a haze of sulfuric acid that further influenced the planet's climate and chemistry.123