<human>:  What are the climate change policies that have been proposed by different countries?
<bot>: Different countries have proposed a range of climate change policies, such as carbon taxes, emissions trading schemes, renewable energy incentives, and support for research into new green technologies. Other policies include increased energy efficiency standards, the promotion of electric vehicles and public transportation options, and subsidies or incentives for low-carbon energy sources. Additionally, many countries have passed legislation or used regulation to limit fossil fuel extraction or promote other green energy sources.