Even though the Chicxulub asteroid is known for the impact that killed off the dinosaurs, it also caused a mass extinction event that changed the evolutionary course for many species. Another profound impact that it had on the planet was hundreds of thousands of years of global warming following the asteroid strike.
Temperatures rose at a higher rate than they are climbing today.
Global Warming After The Asteroid Impact
Scientists have debated on the consequences of the Chicxulub asteroid on the climate of Earth. There has been a debate on whether the impact caused global cooling because of the soot that it produced in the atmosphere that was able to block out the sun. Others have argued that carbon was released from the Earth's crust when the asteroid impact occurred. This, along with the carbon from wildfires, caused global warming during this time.
Scientists from a team of different universities determined that the asteroid impact increased global temperatures by 5 degrees Celsius during that time. The team's findings were published in the journal Science. This temperature increase lasted for 100,000 years after the Chicxulub impact.
Researchers estimate that 65 million years ago, an asteroid that was 6 to 9 miles in size crashed into the Yucatan Peninsula in Mexico. They estimate that temperatures rose exponentially for the first minutes or hours then decreased dramatically due to the amount of dust and soot that blocked out the sun after the impact. Carbon dioxide released during the impact caused global warming that occurred after.
This study is the first to show the impact of the greenhouse gases that were released in this period and to say how long the global warming lasted after the impact.
Analysis Of Fish Fossil In Tunisia
To determine the impact of the Chicxulub impact during that period of time, researchers analyzed sand-grain sized fish teeth, scales, and bones from the El Kef section of Tunisia. In the study, they say that these samples were able to retain oxygen isotopic signatures that show what the temperature of Earth was during the period of time when the animal was alive.
Researchers found that during this time the amount of oxygen isotope, oxygen 16, increased relatively. This would signal a temperature increase. Overall, they analyzed 40 different samples from Tunisia. The samples were: 10 from 50,000 years before the impact, 20 from the 100,000 years after the impact, and 10 more samples from 200,000 after the impact.
The oxygen isotopes found in the samples differed among all the groups of samples. Their research shows that temperatures were able to come back down 100,000 years after all of the carbon dioxide was released into the atmosphere. This could shed light on how long it would take for Earth to recover from the current wave of greenhouse emissions into the atmosphere.
