SUNKEN COSTS

摘要

Paris will host the 21st United Nations Climate Change Conference of the Parties (COP21) in December. The annual conference brings countries together in an effort to tackle climate change and led to the creation of the Kyoto Protocol, an international treaty that requires member states to reduce greenhouse gas emissions. The commitment period ended in 2012,famouslyfailing to meet targets. A second round of commitment is now in action, and member states are once again debating how to tackle the thorny issue of climate change. Alongside reducing carbon emissions, Kyoto also encourages man-made carbon sinks (i.e. ways to take carbon out of the atmosphere to offset emissions). The carbon we emit does not stay in the atmosphere indefinitely, instead it circulates through various sources and sinks: ecosystems, the geosphere, the ocean, and the atmosphere.