Presumably she's referring to her first proposal -- a carbon tax. It's my understanding that there's nearly consensus among economists that a carbon tax is the most efficient solution to global warming, but political consensus that it would never happen when framed as a tax.
If you don't know what a carbon tax is, or why it's orders of magnitude more efficient a solution than "eat less meat" I'd encourage you to look into it a bit. Essentially if you create a system where what is best for the planet is also the cheapest course of action (for individuals and businesses), you no longer have to rely on convincing every single individual to change their morality/beliefs.
2) Another big chunk of the working population would lose their jobs because their industry gets shaken up: Those working in polluting industries (coal and gas) or the huge part of the economy that's surrounding petro-chemicals (gas stations clerks, heating engineers, fuel truck drivers), etc.
You would need to redistribute the CO2 tax income as welfare checks but again: That's not a politically viable solution because the fear of job losses pretty much outweighs anything else.