Query: While it's true that any single country's CO2 emissions reductions will make little difference, only if every nation agrees to limit CO2 emissions can we achieve significant cuts on a global scale.

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Kyoto Protocol <=SEP=> The Kyoto Protocol is an international treaty which extends the 1992 United Nations Framework Convention on Climate Change ( UNFCCC ) that commits State Parties to reduce greenhouse gas emissions , based on the fact that ( a ) global warming exists and ( b ) human-made CO2 emissions have caused it . The Kyoto Protocol was adopted in Kyoto , Japan , on 11 December 1997 and entered into force on 16 February 2005 . There are currently 192 parties ( Canada withdrew effective December 2012 ) to the Protocol .   The Kyoto Protocol implemented the objective of the UNFCCC to fight global warming by reducing greenhouse gas concentrations in the atmosphere to `` a level that would prevent dangerous anthropogenic interference with the climate system '' ( Art. 2 ) . The Protocol is based on the principle of common but differentiated responsibilities : it puts the obligation to reduce current emissions on developed countries on the basis that they are historically responsible for the current levels of greenhouse gases in the atmosphere .   The Protocol 's first commitment period started in 2008 and ended in 2012 . A second commitment period was agreed on in 2012 , known as the Doha Amendment to the protocol , in which 37 countries have binding targets : Australia , the European Union ( and its 28 member states ) , Belarus , Iceland , Kazakhstan , Liechtenstein , Norway , Switzerland , and Ukraine . Belarus , Kazakhstan and Ukraine have stated that they may withdraw from the Protocol or not put into legal force the Amendment with second round targets . Japan , New Zealand and Russia have participated in Kyoto 's first-round but have not taken on new targets in the second commitment period . Other developed countries without second-round targets are Canada ( which withdrew from the Kyoto Protocol in 2012 ) and the United States ( which has not ratified the Protocol ) . As of July 2016 , 66 states have accepted the Doha Amendment , while entry into force requires the acceptances of 144 states . Of the 37 countries with binding commitments , 7 have ratified .   Negotiations were held in the framework of the yearly UNFCCC Climate Change Conferences on measures to be taken after the second commitment period ends in 2020 . This resulted in the 2015 adoption of the Paris Agreement , which is a separate instrument under the UNFCCC rather than an amendment of the Kyoto protocol .

Climate change mitigation <=SEP=> Climate change mitigation consists of actions to limit the magnitude or rate of long-term climate change . Climate change mitigation generally involves reductions in human ( anthropogenic ) emissions of greenhouse gases ( GHGs ) . Mitigation may also be achieved by increasing the capacity of carbon sinks , e.g. , through reforestation . Mitigation policies can substantially reduce the risks associated with human-induced global warming .   According to the IPCC 's 2014 assessment report , `` Mitigation is a public good ; climate change is a case of the ` tragedy of the commons . Effective climate change mitigation will not be achieved if each agent ( individual , institution or country ) acts independently in its own selfish interest ( see international cooperation and emissions trading ) , suggesting the need for collective action . Some adaptation actions , on the other hand , have characteristics of a private good as benefits of actions may accrue more directly to the individuals , regions , or countries that undertake them , at least in the short term . Nevertheless , financing such adaptive activities remains an issue , particularly for poor individuals and countries . ''   Examples of mitigation include phasing out fossil fuels by switching to low-carbon energy sources , such as renewable and nuclear energy , and expanding forests and other `` sinks '' to remove greater amounts of carbon dioxide from the atmosphere . Energy efficiency may also play a role , for example , through improving the insulation of buildings . Another approach to climate change mitigation is climate engineering .   Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) . The ultimate objective of the UNFCCC is to stabilize atmospheric concentrations of GHGs at a level that would prevent dangerous human interference of the climate system . Scientific analysis can provide information on the impacts of climate change , but deciding which impacts are dangerous requires value judgments .   In 2010 , Parties to the UNFCCC agreed that future global warming should be limited to below 2.0 ° C ( 3.6 ° F ) relative to the pre-industrial level . With the Paris Agreement of 2015 this was confirmed , but was revised with a new target laying down `` parties will do the best '' to achieve warming below 1.5 ° C . The current trajectory of global greenhouse gas emissions does not appear to be consistent with limiting global warming to below 1.5 or 2 ° C . Other mitigation policies have been proposed , some of which are more stringent or modest than the 2 ° C limit .

Emissions trading <=SEP=> Emissions trading or cap and trade is a government-mandated , market-based approach to controlling pollution by providing economic incentives for achieving reductions in the emissions of pollutants . In contrast to command-and-control environmental regulations such as best available technology ( BAT ) standards and government subsidies , cap and trade ( CAT ) schemes are a type of flexible environmental regulation that allows organizations to decide how best to meet policy targets . Various countries , states and groups of companies have adopted such trading systems , notably for mitigating climate change .   A central authority ( usually a governmental body ) allocates or sells a limited number of permits to discharge specific quantities of a specific pollutant per time period . Polluters are required to hold permits in amount equal to their emissions . Polluters that want to increase their emissions must buy permits from others willing to sell them . Financial derivatives of permits can also be traded on secondary markets .   In theory , polluters who can reduce emissions most cheaply will do so , achieving the emission reduction at the lowest cost to society . Cap and trade is meant to provide the private sector with the flexibility required to reduce emissions while stimulating technological innovation and economic growth .   There are active trading programs in several air pollutants . For greenhouse gases , which cause climate change , permit units are often called carbon credits . The largest greenhouse gases trading program is the European Union Emission Trading Scheme , which trades primarily in European Union Allowances ( EUAs ) ; the Californian scheme trades in California Carbon Allowances , the New Zealand scheme in New Zealand Units and the Australian scheme in Australian Units . The United States has a national market to reduce acid rain and several regional markets in nitrogen oxides .

Global warming <=SEP=> Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years .   In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing .   Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years .   Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) ,  whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change .   Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .