Reuters: The province of Ontario, Canada’s industrial heartland, will join the Western Climate Initiative, a planned U.S.-based regional carbon credit trading pact, the province’s premier, Dalton McGuinty, said on Friday. Ontario is the fourth Canadian province, after British Columbia, Manitoba and Quebec, to sign up to the grouping, which includes California and six other U.S. states. The initiative was established by U.S. state governors fed up with what they saw as the Bush …