How the darkness and the cold killed the dinosaurs | EurekAlert! Science News
https://www.eurekalert.org/pub_releases/2017-01/pifc-htd011317.php
66 million years ago, the sudden extinction of the dinosaurs started the ascent of the mammals, ultimately resulting in humankind's reign on Earth.
Climate scientists now reconstructed how tiny droplets of sulfuric acid formed high up in the air after the well-known impact of a large asteroid
and blocking the sunlight for several years, had a profound influence on life on Earth. Plants died, and death spread through the food web. Previous
theories focused on the shorter-lived dust ejected by the impact. The new computer simulations show that the droplets resulted in long-lasting cooling,
a likely contributor to the death of land-living dinosaurs. An additional kill mechanism might have been a vigorous mixing of the oceans, caused by
the surface cooling, severely disturbing marine ecosystems.
"The big chill following the impact of the asteroid that formed the Chicxulub crater in Mexico is a turning point in Earth history," says Julia Brugger
from the Potsdam Institute for Climate Impact Research (PIK), lead author of the study to be published today in the Geophysical Research Letters. "We
can now contribute new insights for understanding the much debated ultimate cause for the demise of the dinosaurs at the end of the Cretaceous era."
To investigate the phenomenon, the scientists for the first time used a specific kind of computer simulation normally applied in different contexts,
a climate model coupling atmosphere, ocean and sea ice. They build on research showing that sulfur- bearing gases that evaporated from the violent
asteroid impact on our planet's surface were the main factor for blocking the sunlight and cooling down Earth.
