Seems to me that "climate change" is a very generic term to be using as a cause of mass extinctions...
It can be caused apparently by many, many things. It's only a result of other things happening.
Seems to me, in order to prevent the extinctions, must needs be a bit more specific as to the causation of global "climate change". Be it farts,
volcanos, asteroids, whatever...
Asteroids several times smaller than a planet can do disproportionate damage. An asteroid can cause mass-extinction (this is what is thought to have
made the dinosaurs go extinct) through major climate change. When an asteroid impacts a planet, there is a massive explosion and all the kinetic and
heat energy from the impact creates a crater several times larger than the asteroid itself. The impact (if on land) throws up massive amounts of rock
and dust, if there is enough debris, there will like be a large dust cloud for several years.
If the asteroid impacts on water, it can create a massive tsunami, or tidal wave, that can do massive destruction to shoreline communities.
The theories made now days are becoming a LOT easier to prove/disprove due to the large amounts of information gathered, shared, and possibly
simulated in our communications / information era.