In December 2006, Dr. Mark Trexler authored a controversial paper called A Consumer’s Guide to Retail Carbon Offset Providers. He studied and ranked the numerous firms selling carbon offsets - also known as carbon credits - and named several firms with credible products. However, some of the most popular companies in the fledgling industry came out smelling, well, rather bad. The report caused quite a flap.

Dr. Trexler is Managing Director of EcoSecurities Global Consulting Services, an international carbon trading and consulting firm. I caught up with him at the noisy EUEC Energy and Environment Conference held at the end of every January in the foothills of Tucson, Arizona. Scientists, policy makers and business leaders from around the world gathered to tackle the fabulously difficult issues of climate change and energy.

Here are Dr. Trexler’s thoughts on topics including whether the Federal Trade Commission will find fraud in the carbon market during its ongoing investigation, when he thinks carbon credits work, and whether to buy them.

A couple of notes in case you’re not familiar with terms used in this piece. Additionality describes whether a project that is the beneficiary of carbon credit funds objectively reduces atmospheric CO2 or not. The Chicago Climate Exchange is one of a number of groups that's similar to a stock exchange for the carbon market. HFC-23 is a greenhouse gas almost 12,000 times more potent than CO2.

Here’s our conversation.

Music courtesy of: Tucson’s own Tesoro for Pistolero, and my good friends Opencloud for Shark Repellant, the Life and Chronicles of Sir Jason of Planet Doobias, and Do It Now.

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