A study that analyzed the seven potential effects posed by potential asteroid impacts on Earth found violent winds and shock waves to be the most dangerous consequences.
University of Southampton senior research assistant Clemens Rumpf led a team of researchers who used computer models to simulate the impacts of 50,000 different asteroids on Earth ranging in size from 49 to 1312 feet (15 to 400 meters) in diameter.
The simulation included both land- and ocean-based impacts.
Asteroid impacts can produce seven effects–heat, flying debris, pressure shock waves, wind blasts, tsunamis, cratering, and seismic shaking.
For each asteroid in the simulation, the researchers estimated how many lives would be lost under each of these seven effects.
They found that more than 60 percent of the lives that would be lost in the aftermath of an asteroid impact to result from wind blasts and shockwaves.
Impacts can produce a rapid increase in atmospheric pressure, generating shock waves capable of rupturing internal organs.
Violent winds resulting from an impact are strong enough to lift and throw people and destroy entire forests.
“This is the first study that looks at all seven impacts generated by hazardous asteroids and estimates which are, in terms of human loss, most severe,” said Rumpf, who is the lead author of a study on the findings published in the journal Geophysical Research Letters.
Asteroids that hit land would produce significantly more casualties than those that hit oceans, the study found.
Ocean impacts can generate tsunamis, but the tsunamis would dissipate as they moved and break entirely once they reach the edge of a continent.
The study indicated just 20 percent of lives lost due to an impact would be caused by tsunamis.
Heat from an impact would be responsible for about 30 percent of lives lost, but its consequences could be avoided by people taking shelter in basements and underground shelters.
Seismic shaking, cratering, and flying debris accounted for very small numbers of casualties.
To have potentially lethal consequences, an asteroid must be at least 60 feet (18 meters) wide. The majority of asteroids that hit the Earth are smaller than this and break up in the atmosphere.
Four years ago, the meteor that hit Chelyabinsk in Russia was about 55 to 65 feet (17 to 20 meters) in diameter. It exploded in the air, injuring 1,000 but caused no fatalities.
Rumpf emphasized the chances of hazardous asteroids impacting the Earth are very low. Studies like this one are done to provide crucial knowledge on avoiding harm in the rare chance of an occurrence.