OK. Since you seem to think that science can prove "orbital variation" hundreds of thousands of years ago. The Medeivel Warn Period which WARMED up, lasted about 300 years, then, wait for it, wait for it, it cooled! I bet that too was "orbital variation"...... Try using your brain and study history. 
If you have any children I feel sad that you want to brain wash them into thinking that their existence and the progress of humanity is to blame for something none of us can control. 
Don't be a hypocrite: stop driving, taking warm showers, using indoor plumbing, flying, using your computer, cell phone, turning on your lights and warming your house. With your logic, you're killing all of us with your actions.