Because the changes were seeing are way way way faster then has ever been recorded without a natural disaster like a meteor hit. What the last ice age took 10,000 years to do, were gonna have done in under 200, but that number keeps dropping every year. Look at FL winter this year. We had 50 hours under 45f. Thats it. Never even froze. World wide march broke 7,725 weather records. My gardens overridden with leaf miners because the winter didn't knock em back but it did knock their predators back. So the farms and gardens are infested wth them till the wasp families populations build up. I've grown here my whole life and this is the second time I've seen leaf miners, and before it was 1 plant. Their tearing up my squash, basil, tomatoes, cantalope, peppers,etc....... Climate change is fact, we caused it because no volcano's blew and no meteors hit in the last 100 years. So its obviously our fault. Also explain the 800% increase in melanoma in people ages 18-35. I bring this up because my brother just had a surgery on his back removing a lot of it last month, and my mother just had it removed last week. Other then that we have no history of cancer in our families.The Earths CLIMATE has become colder(ice-age) and warmer, repeatedly throughout history.
We only began using "fossil" fuels a little over 200 hundred years ago.
If the Earth has had cooling and warming cycles long before humans even existed, how can anyone believe that WE are the cause of climate change?