Discuss some of the carbon trading systems in existence today. Must be atleast three hundred words.

Here's an example to that question, hopefully its helpful.

"The EU first started trading emissions in 2005. It was considered to be the "first multi-national emissions trading scheme in the world and is considered a forerunner of the international emissions trading scheme under the Kyoto Protocol". Joint Implementation is also another system in carbon trading. In the article it states that JI is project based. Therefore, the credits go wherever the project takes place. So the credits basically travel along with the project, even if it were to move from one country to another. A third system is called the Clean Development Mechanism (CDM). The definition states the following, "CDM credits to offset an increase in their domestic emissions during a commitment period." I still don't really understand the third one but the first two are pretty self-explanatory. If anyone understands the third system, I'd really appreciate if you could try explaining it to me in an easier manner."