A new study carried out by researchers from the Potsdam Institute of Climate Impact Research (PIK) suggests that the dinosaur era on Earth ended because of the dark and chill that resulted following the megastrike of an Asteroid 65 million years ago.

Previous theories on extinction of Dinosaurs from Earth blame short-lived dust created by the impact as the main reason behind end of dinosaur period on Earth.

Asteroid megastrike

It is a well known fact that a huge asteroid slammed into the Gulf of Mexico about 65 million years ago and blocked the sunlight for many years.

The new study attempted to recreate the apocalyptic time that is believed to have completely wiped out the dinosaurs from Earth. The team carried out a computer simulation study, which suggest that after the megastrike of the asteroid, little drops of sulfuric acid created high up in the atmosphere and completely blocked the sunlight for many years. The "big chill" that resulted from blocking of sunlight had catastrophic effects on Earth. It caused global temperatures to drop for three years, mixed oceans, and also killed marine life. Plants and animals on surface also started to die. Presence of sulfuric acid droplets in Earth’s atmosphere caused long-lasting cooling. The annual mean surface air temperature plummeted by about 26 degrees Celsius, to lower than freezing point.

Even in tropics, the temperature dropped from 27 degrees C to just five degrees Celsius. Since dinosaurs were accustomed to living in lush green surroundings, they could not bear such low temperatures, and eventually became extinct.

"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 PIK and the lead author of the study.

Climate recovery

According to researchers, it took almost 30 years for the climate to recover from the massive change. Co-author Georg Feulner thinks the long-term cooling resulting due to sulfate aerosols was more important for the mass extinction of dinosaurs than the dust that stayed in the atmosphere for a shorter period of time. The detailed findings of the study have been published in the Geophysical Research Letters.