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How did sulfur released by the Chicxulub impact affect the atmosphere and oceans?

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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 Chicxulub impact, which occurred approximately 66 million years ago, involved the collision of an asteroid with a region of Earth's crust that was rich in sulfur-bearing minerals. Because the impact site lacked significant sulfur content in its remaining geological record, it is concluded that the event vaporized these minerals, releasing several hundred gigatons of sulfur into the atmosphere.12

This massive release of sulfur created a global haze of sulfuric acid. This atmospheric change likely triggered acid rain, which contributed to the acidification of the oceans. By altering the chemical composition of the marine environment, this process—coupled with the cessation of photosynthesis caused by dust-induced darkness—led to the widespread death of plankton and other marine organisms, ultimately disrupting the food chain and contributing to the K–T extinction event.23