About 66 million years ago, a colossal asteroid collided with Earth, creating the immense Chicxulub crater. This event triggered a worldwide winter and caused the widespread extinction of dinosaurs.
However, recent models indicate that a key factor in these drastic changes was the dust produced by the impact.
The widely accepted theory is that freezing temperatures played a major role in the extinction of dinosaurs; meanwhile, the enigma lies in understanding how the asteroid impact precipitated such a rapid climate shift.
A recent study published in Nature Geoscience points to silicate dust as the culprit because, when the asteroid struck the Yucatan Peninsula in Mexico, it propelled vast amounts of this dust into the atmosphere.
The Earth was enveloped in a dense layer of dust so extensive that it obscured the sun. This not only caused significant cooling but also had a critical impact on plant life.
Without sunlight, plants worldwide were unable to perform photosynthesis. In just 14 days following the asteroid collision, all photosynthesis had ceased.
Models indicate that this state persisted for 620 days, which is nearly two years.
The absence of photosynthesis led to a rapid die-off of plants, essentially erasing the primary level of nearly all of Earth’s food chains. Survival was only possible mainly for animals and plants capable of hibernation. So, as a result, 75% of all species on the planet perished.
Then, photosynthesis returned to its normal levels about four years following the impact. Nonetheless, the dust lingered in the atmosphere for an additional 11 years, maintaining the long 15-year winter period.