EMISSIONS ESTIMATES: Alberta's oil-sands companies are required to reduce the intensity of their greenhouse-gas emissions under the province's emissions trading scheme.Image: . RALSTON/AFP/Getty
Alberta’s $57 million carbon-cutting program is failing, according to the latest report from the Canadian province’s auditor-general, Merwan Saher. Like many such programs around the world, it includes an emissions trading scheme, which allows polluters to meet their emissions reductions targets by buying carbon offsets from a selection of approved projects. The offsets are supposed to be real, measurable and provable. But the report claims that the province, despite earlier warnings, has not improved its regulatory structure—and calls the emissions estimates and the offsets themselves into question.
Nature looks at the hurdles faced by Alberta and other jurisdictions over their emissions trading schemes.