One question that is often asked is this: What is actually being done to limit the amount of carbon emissions? One policy that is doing a good job of this is the EU Emissions Trading System, or EU ETS. This policy puts a limit on how much carbon can be emitted by things like power plants or factories. Companies buy or receive emission allowances, and they can trade these allowances with one another as needed. It also states that companies that reduce their emissions can keep the allowance from cover its future needs, or it can sell them to another company. Even airlines are affected by this policy, and all flights in and out of the EU are regulated for their carbon emissions. This policy has gotten a lot of response, one negative one being from the United States. In 2012, a act was passed "to prohibit operators of civil aircraft in the United States from participating in the European Union's emissions trading scheme". Although it has gotten some negative response, this system has been, and will further, decrease the amount of carbon emissions in the EU.

A detailed desc ription of this system can be found here: http://ec.europa.eu/clima/policies/ets/index_en.htm
The U.S. act prohibiting this can be found here:
http://www.gpo.gov/fdsys/pkg/PLAW-112pu … ubl200.pdf