I suggest rather than pointing at people not believing in climate change, pointing at why people don't believe Climate change would be better.
1. Because of the effects of activities which have drastic effect on Climate change are not immediate
2. Because the effects of those activities are faced by future generation
these points will help you.
Add few more points on Ongoing water crisis in different parts of world. Tell how your country could be next in line of water crisis. Tell the effects of Climate change on Human health ( genetic changes it causes that could lead to defective babies) Tell the economic burden. Climate change effects on Agriculture that could lead to food crisis.
Finally few points on how to address it.
1. Planting trees
2. Conserving Electricity
3. Conserving Water
4. Using Public transport
and so on