The idea is to make carbon pollution more expensive so people will use less fossil fuel
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/tax-carbon-emissions-could-soon-be-reality-washington-state
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/business-standard-new-delhi
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/carbon-dioxide
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/carbon-tax
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/climate-change
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/hydroelectricity