The Kyoto Protocol (Japanese: 京都議定書, Hepburn: Kyōto Giteisho) was an international treaty which extended the 1992 United Nations Framework Convention on Climate Change (UNFCCC) that commits state parties to reduce greenhouse gas emissions, based on the scientific consensus that global warming is occurring and that human-made CO2 emissions are driving it. The Kyoto Protocol was adopted in Kyoto, Japan, on 11 December 1997 and entered into force on 16 February 2005. There were 192 parties (Canada withdrew from the protocol, effective December 2012) to the Protocol in 2020.
An emission intensity is the emission rate of a given pollutant relative to the intensity of a specific activity, or an industrial production process; for example grams of carbon dioxide released per megajoule of energy produced, or the ratio of greenhouse gas emissions produced to gross domestic product (GDP). Emission intensities are used to derive estimates of air pollutant or greenhouse gas emissions based on the amount of fuel combusted, the number of animals in animal husbandry, on industrial production levels, distances traveled or similar activity data. Emission intensities may also be used to compare the environmental impact of different fuels or activities. In some case the related terms emission factor and carbon intensity are used interchangeably. The jargon used can be different, for different fields/industrial sectors; normally the term "carbon" excludes other pollutants, such as particulate emissions. One commonly used figure is carbon intensity per kilowatt-hour (CIPK), which is used to compare emissions from different sources of electrical power.
Climate change mitigation (or decarbonisation) is action to limit the greenhouse gases in the atmosphere that cause climate change. Climate change mitigation actions include conserving energy and replacing fossil fuels with clean energy sources. Secondary mitigation strategies include changes to land use and removing carbon dioxide (CO2) from the atmosphere. Current climate change mitigation policies are insufficient as they would still result in global warming of about 2.7 °C by 2100, significantly above the 2015 Paris Agreement's goal of limiting global warming to below 2 °C.
A carbon footprint (or greenhouse gas footprint) is a calculated value or index that makes it possible to compare the total amount of greenhouse gases that an activity, product, company or country adds to the atmosphere. Carbon footprints are usually reported in tonnes of emissions (CO2-equivalent) per unit of comparison. Such units can be for example tonnes CO2-eq per year, per kilogram of protein for consumption, per kilometer travelled, per piece of clothing and so forth. A product's carbon footprint includes the emissions for the entire life cycle. These run from the production along the supply chain to its final consumption and disposal.
Land use, land-use change, and forestry (LULUCF), also referred to as Forestry and other land use (FOLU) or Agriculture, Forestry and Other Land Use (AFOLU), is defined as a "greenhouse gas inventory sector that covers emissions and removals of greenhouse gases resulting from direct human-induced land use such as settlements and commercial uses, land-use change, and forestry activities."
Greenhouse gas inventories are emission inventories of greenhouse gas emissions that are developed for a variety of reasons. Scientists use inventories of natural and anthropogenic (human-caused) emissions as tools when developing atmospheric models. Policy makers use inventories to develop strategies and policies for emissions reductions and to track the progress of those policies.
Greenhouse gas (GHG) emissions from human activities intensify the greenhouse effect. This contributes to climate change. Carbon dioxide, from burning fossil fuels such as coal, oil, and natural gas, is one of the most important factors in causing climate change. The largest emitters are China followed by the United States. The United States has higher emissions per capita. The main producers fueling the emissions globally are large oil and gas companies. Emissions from human activities have increased atmospheric carbon dioxide by about 50% over pre-industrial levels. The growing levels of emissions have varied, but have been consistent among all greenhouse gases. Emissions in the 2010s averaged 56 billion tons a year, higher than any decade before. Total cumulative emissions from 1870 to 2022 were 703 GtC, of which 484±20 GtC from fossil fuels and industry, and 219±60 GtC from land use change. Land-use change, such as deforestation, caused about 31% of cumulative emissions over 1870–2022, coal 32%, oil 24%, and gas 10%.
The United States produced 5.2 billion metric tons of carbon dioxide equivalent greenhouse gas (GHG) emissions in 2020, the second largest in the world after greenhouse gas emissions by China and among the countries with the highest greenhouse gas emissions per person. In 2019 China is estimated to have emitted 27% of world GHG, followed by the United States with 11%, then India with 6.6%. In total the United States has emitted a quarter of world GHG, more than any other country. Annual emissions are over 15 tons per person and, amongst the top eight emitters, is the highest country by greenhouse gas emissions per person.
A low-carbon diet is any diet that results in lower greenhouse gas emissions. Choosing a low carbon diet is one facet of developing sustainable diets which increase the long-term sustainability of humanity. Major tenets of a low-carbon diet include eating a plant-based diet, and in particular little or no beef and dairy. Low-carbon diets differ around the world in taste, style, and the frequency they are eaten. Asian countries like India and China feature vegetarian and vegan meals as staples in their diets. In contrast, Europe and North America rely on animal products for their Western diets.
The climate policy of China is to peak its greenhouse gas emissions before 2030 and to be carbon neutral before 2060. Due to the buildup of solar power and the burning of coal, Chinese energy policy is closely related to its climate policy. There is also policy to adapt to climate change. Ding Xuexiang represented China at the 2023 United Nations Climate Change Conference in 2023, and may be influential in setting climate policy.
Greenhouse gas emissions by Australia totalled 533 million tonnes CO2-equivalent based on greenhouse gas national inventory report data for 2019; representing per capita CO2e emissions of 21 tons, three times the global average. Coal was responsible for 30% of emissions. The national Greenhouse Gas Inventory estimates for the year to March 2021 were 494.2 million tonnes, which is 27.8 million tonnes, or 5.3%, lower than the previous year. It is 20.8% lower than in 2005. According to the government, the result reflects the decrease in transport emissions due to COVID-19 pandemic restrictions, reduced fugitive emissions, and reductions in emissions from electricity; however, there were increased greenhouse gas emissions from the land and agriculture sectors.
In 2021, net greenhouse gas (GHG) emissions in the United Kingdom (UK) were 427 million tonnes (Mt) carbon dioxide equivalent, 80% of which was carbon dioxide itself. Emissions increased by 5% in 2021 with the easing of COVID-19 restrictions, primarily due to the extra road transport. The UK has over time emitted about 3% of the world total human caused CO2, with a current rate under 1%, although the population is less than 1%.
Representative Concentration Pathways (RCP) are climate change scenarios to project future greenhouse gas concentrations. These pathways describe future greenhouse gas concentrations and have been formally adopted by the IPCC. The pathways describe different climate change scenarios, all of which were considered possible depending on the amount of greenhouse gases (GHG) emitted in the years to come. The four RCPs – originally RCP2.6, RCP4.5, RCP6, and RCP8.5 – are labelled after a possible range of radiative forcing values in the year 2100. The IPCC Fifth Assessment Report (AR5) began to use these four pathways for climate modeling and research in 2014. The higher values mean higher greenhouse gas emissions and therefore higher global surface temperatures and more pronounced effects of climate change. The lower RCP values, on the other hand, are more desirable for humans but would require more stringent climate change mitigation efforts to achieve them.
The amount of greenhouse gas emissions from agriculture is significant: The agriculture, forestry and land use sectors contribute between 13% and 21% of global greenhouse gas emissions. Emissions come from direct greenhouse gas emissions. And from indirect emissions. With regards to direct emissions, nitrous oxide and methane makeup over half of total greenhouse gas emissions from agriculture. Indirect emissions on the other hand come from the conversion of non-agricultural land such as forests into agricultural land. Furthermore, there is also fossil fuel consumption for transport and fertilizer production. For example, the manufacture and use of nitrogen fertilizer contributes around 5% of all global greenhouse gas emissions. Livestock farming is a major source of greenhouse gas emissions. At the same time, livestock farming is affected by climate change.
China's total greenhouse gas emissions are the world's highest of any country, accounting for 35% of the world's total according to the International Energy Agency. The country's per capita greenhouse gas emissions are the 34th highest of any country, as of 2023.
Greenhouse gas emissionsbyRussia are mostly from fossil gas, oil and coal. Russia emits 2 or 3 billion tonnes CO2eq of greenhouse gases each year; about 4% of world emissions. Annual carbon dioxide emissions alone are about 12 tons per person, more than double the world average. Cutting greenhouse gas emissions, and therefore air pollution in Russia, would have health benefits greater than the cost. The country is the world's biggest methane emitter, and 4 billion dollars worth of methane was estimated to leak in 2019/20.
World energy supply and consumption refers to the global supply of energy resources and its consumption. The system of global energy supply consists of the energy development, refinement, and trade of energy. Energy supplies may exist in various forms such as raw resources or more processed and refined forms of energy. The raw energy resources include for example coal, unprocessed oil & gas, uranium. In comparison, the refined forms of energy include for example refined oil that becomes fuel and electricity. Energy resources may be used in various different ways, depending on the specific resource, and intended end use. Energy production and consumption play a significant role in the global economy. It is needed in industry and global transportation. The total energy supply chain, from production to final consumption, involves many activities that cause a loss of useful energy.
