Climate change crusader Al Gore praises Ontario's cap and trade system during Toronto visit

Former U.S. vice-president and climate change crusader Al Gore is praising Ontario's cap-and-trade system, calling it better than a carbon tax.

Gore,who sat downwith Premier Kathleen Wynnein a one-on-one interview in front of hundreds of students at RyersonUniversity on Thursday, says the way Ontario currently fights climate change is the "superior" system.

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He says cap and trade lets government work directly with emitters to cut carbon emissions over time.

Carbon pricing is shaping up to be a key issue in the province's spring election, with all four candidatesvying to lead the opposition Progressive Conservatives vowing to scrap cap-and-trade and fight the imposition of a federal carbon tax, if they're elected June 7.

Gore praised Wynne for her Liberal government's efforts to fight climate change and took a shot at theTory leadership hopefuls, saying their proposals would set the province back.

Ontario's cap-and-trade system, launched last year, is aimed at lowering greenhouse gas emissions by putting caps on the amount of pollution companies in certain industries can emit. If they exceed those limits they must buy allowances at quarterly auctions or from other companies that come in under their limits.

'Optimism and hope'

Among the university students werearound 200students from various high schools who were invited to the talk in downtown Toronto. They each hailed from one of Ontario's nearly 2,000 certified EcoSchools a program which "focuses on environmental action and learning," according to Lindsay Bunce, the executive director of Ontario EcoSchools.

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"Access to leadershiplikethis, and access to innovation and ... the reinforcement of the positivity and optimism around climate change is so critical for these students to hear," she told CBCToronto.

"It wascriticalthat an event like this isfocusedon optimism and hope."

Juliana Melina and Darren Joseph, students atFrancis Libermann Catholic High School, both attended the talk on Thursday.

"[Gore]really told us that we had to take action, that we can and that we will or should," said Melina.

Joseph explained that his school is holding an environmental conference this year, and that they regularly host cleanups around the property.

"We've done so much, and we want to follow in Al Gore's footsteps to be a better school and to make a better world," he said.