Global warming is when the sun gives off heat to earth and earth’s greenhouse gases keeps the warmth on the earth.Earth’s blanket gets thicker which keeps in more heat.
One of the biggest climate change problems is ice glaciers melting. The ice glaciers melting causes acidity. It kills the plankton which gives us 50% of our oxygen.
Renewable energy does not release greenhouse gasses. Nonrenewable energy does, and it takes a very long time to renew (half a million - a million years)