Yep - that's what's being suggested.
Of course, it's only 'rich' countries that will be subject to the tax,despite the fact that 'countries' don't actually purchase plane tickets...
And then there are the super rich who don't purchase tickets, but fly in private planes.
What are the implications? Well, if you make ticket prices higher, the individuals who would normally purchase them might decide not to. That will result in less tourism across the globe - and less 'income' from the tax. Businesses who have no choice but to travel internationally will pass along those increased taxes to the individuals who purchase their products, causing an overall increase in costs, as well.
Then there is the suggestion to match the plane ticket tax with a shipping fuel tax. Of course, that drives up the costs of commerce - again making products more expensive.
The worst part of all this is that the billion and trillions 'they' want to spend to combat global warming may - just maybe - reduce temperatures by a fraction of a degree. Is a fraction of a degree really worth the extra cost?
The core problem, however, is that everyone just assumes that our current temperature is the 'right' one and that it must be preserved. Personally, I'd like it to be a bit warmer, especially during the winter months. And who can tell us, with any amount of authority whatsoever, what the 'proper' temperature of the earth should be so that we can aspire to reach it?
If you read the linked article, you'll see that another complaint from the conference is that 'rich' countries aren't giving enough money to the 'poor' countries. That whole 'redistribute the wealth' idea doesn't work - all it does is make the 'rich' want to stop producing. As Margaret Thatcher said, 'eventually you run out of other people's money.'