Chixculub: created a nasty cauldron and more (Introduction)

by David Turell , Tuesday, June 30, 2020, 00:33 (1390 days ago) @ David Turell

More support the impact was the major factor in the dinosaur rub out:

https://phys.org/news/2020-06-asteroid-impact-volcanoes-earth-uninhabitable.html

"Modelling of the Chicxulub asteroid impact 66 million years ago shows it created a world largely unsuitable for dinosaurs to live in.

"The asteroid, which struck the Earth off the coast of Mexico at the end of the Cretaceous era 66 million years ago, has long been believed to be the cause of the demise of all dinosaur species except those that became birds.

"However, some researchers have suggested that tens of thousands of years of large volcanic eruptions may have been the actual cause of the extinction event, which also killed off almost 75% of life on Earth.

"Now, a research team from Imperial College London, the University of Bristol and University College London has shown that only the asteroid impact could have created conditions that were unfavourable for dinosaurs across the globe.

"They also show that the massive volcanism could also have helped life recover from the asteroid strike in the long term.

"'We show that the asteroid caused an impact winter for decades, and that these environmental effects decimated suitable environments for dinosaurs. In contrast, the effects of the intense volcanic eruptions were not strong enough to substantially disrupt global ecosystems.

"'Our study confirms, for the first time quantitatively, that the only plausible explanation for the extinction is the impact winter that eradicated dinosaur habitats worldwide."

***

"'In this study we add a modelling approach to key geological and climate data that shows the devastating effect of the asteroid impact on global habitats. Essentially, it produces a blue screen of death for dinosaurs."

"Although volcanoes release Sun-blocking gases and particles, they also release carbon dioxide, a greenhouse gas. In the short term after an eruption, the Sun-blockers have a larger effect, causing a 'volcanic winter'. However, in the longer term these particles and gases drop out of the atmosphere, while carbon dioxide stays around and builds up, warming the planet.

"After the initial drastic global winter caused by the asteroid, the team's model suggests that in the longer term, volcanic warming could have helped restore many habitats, helping new life that evolved after the disaster to thrive."

Comment: From either cause they are gone, but this study adds to our knowledge, and we've still ended up with beautiful birds.