The consequences of climate change might not be as bad as the consequences of preventing it. That's a pretty important thing to figure out because what if you end up creating a bigger calamity than you prevent?

What does "heavy losses" mean? If you don't quantify it, it means the same as "light losses". Is it worse than WWII? Worse than WWI? Worse than Communism? Worse than the Spanish Flu? Worse than AIDS? Worse than malaria? Worse than smoking? These things each killed many millions in the past century and somehow civilization has never been better!

So before worrying about preaching, first figure it out yourself. Otherwise you're nothing more than an amplifier for some other activist's arbitrary emotions.