The greenhouse effect occurs when greenhouse gases in a planet's atmosphere insulate the planet from losing heat to space, raising its surface temperature. Surface heating can happen from an internal heat source or come from an external source, such as its host star. In the case of Earth, the Sun emits shortwave radiation (sunlight) that passes through greenhouse gases to heat the Earth's surface. In response, the Earth's surface emits longwave radiation that is mostly absorbed by greenhouse gases. The absorption of longwave radiation prevents it from reaching space, reducing the rate at which the Earth can cool off.
The geography of Toronto, Ontario, covers an area of 630 km2 (240 sq mi) and is bounded by Lake Ontario to the south; Etobicoke Creek, Eglinton Avenue, and Highway 427 to the west; Steeles Avenue to the north; and the Rouge River and the Scarborough–Pickering Townline to the east. In addition to Etobicoke Creek and the Rouge River, the city is trisected by two minor rivers and their tributaries, the Humber River in the west end and the Don River east of downtown. Both flow southward to Lake Ontario at Humber Bay and Toronto Harbour respectively, which are part of the longer Waterfront, as well as Etobicoke Creek and the Rouge River.
The city of Vancouver, located in British Columbia, Canada, has a temperate oceanic climate. Its summer months are typically dry and modestly warm, while the rest of the year is rainy, especially between October and March. The region has frequent cloudy and overcast skies during the late fall, winter, and spring.
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 the main cause of climate change. The largest annual emissions are from 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.
Climate change has been a critical issue in Australia since the beginning of the 21st century. Australia is becoming hotter and more prone to extreme heat, bushfires, droughts, floods, and longer fire seasons because of climate change. Climate issues include wildfires, heatwaves, cyclones, rising sea levels, and erosion.
Montreal is the second largest city in Canada and the largest city in the province of Quebec, located along the Saint Lawrence River at its junction with the Ottawa River. The city is geographically constrained, with the majority on the Island of Montreal in the Hochelaga Archipelago, and has several prominent features, including the eponymous Mount Royal. The region experiences four distinct seasons and is classified as a humid continental climate, with very cold and snowy winters and warm and humid summers.
Climate change has serious effects on Russia's climate, including average temperatures and precipitation, as well as permafrost melting, more frequent wildfires, flooding and heatwaves. Changes may affect inland flash floods, more frequent coastal flooding and increased erosion reduced snow cover and glacier melting, and may ultimately lead to species losses and changes in ecosystem functioning.
The climate of Finland is influenced most by its latitude: Finland is located between 60 and 70 N. Because of Finland's northern location, winter is the longest season. Only on the south coast and in the southwest is summer as long as winter. On average, winter lasts from early January to late February in the outermost islands in the archipelago and the warmest locations along the southwestern coast – notably in Hanko – and from early October to mid May in the most elevated locations, such as northwestern Lapland and the lowest valleys in northeastern Lapland. This means that southern portions of the country are snow-covered about three to four months of the year, and the northern for about seven months. The long winter causes about half of the annual 500 to 600 millimetres precipitation in the north to fall as snow. Precipitation in the south amounts to about 600 to 700 millimetres annually. Like that of the north, it occurs all through the year, though not so much of it is snow.
Greenhouse gases (GHGs) are the gases in the atmosphere that raise the surface temperature of planets such as the Earth. What distinguishes them from other gases is that they absorb the wavelengths of radiation that a planet emits, resulting in the greenhouse effect. The Earth is warmed by sunlight, causing its surface to radiate heat, which is then mostly absorbed by greenhouse gases. Without greenhouse gases in the atmosphere, the average temperature of Earth's surface would be about −18 °C (0 °F), rather than the present average of 15 °C (59 °F).
Climate change has received significant scientific, public and political attention in Sweden. In 1896, Swedish chemist Svante Arrhenius was the first scientist to quantify global heating. Sweden has a high energy consumtion per capita, but reducing the dependency on fossil energy has been on the agenda of cabinets of the Governments of Sweden since the 1970s oil crises. In 2014 and 2016, Sweden was ranked #1 in the Global Green Economy Index (GGEI), because the Swedish economy produces relatively low emissions. Sweden has had one of the highest usages of biofuel in Europe and aims at prohibiting new sales of fossil-cars, including hybrid cars, by 2035, and for an energy supply system with zero net atmospheric greenhouse gas emissions by 2045.
Climate change is greatly impacting Canada's environment and landscapes. Extreme weather has become more frequent and severe because of the continued release of greenhouse gases into the atmosphere. The number of climate change–related events, such as the 2021 British Columbia Floods and an increasing number of forest fires, has become an increasing concern over time. Canada's annual average temperature over land warmed by 1.7 °C (3.1 °F) between 1948 and 2016. The rate of warming is highest in Canada's north, the Prairies, and northern British Columbia. The country's precipitation has increased in recent years and wildfires expanded from seasonal events to year-round threats.
The south of Sweden has a temperate climate, despite its northern latitude, with largely four distinct seasons and mild temperatures throughout the year. The winter in the far south is usually weak and is manifested only through some shorter periods with snow and sub-zero temperatures, autumn may well turn into spring there, without a distinct period of winter. The northern parts of the country have a subarctic climate while the central parts have a humid continental climate. The coastal south can be defined as having either a humid continental climate using the 0 °C isotherm, or an oceanic climate using the –3 °C isotherm.
Belgium has the 7th largest CO2 emission per capita in the EU. The CO2 emissions have dropped 19.0% since in comparison with 1990 levels. The average temperature has risen 1.9 degrees Celsius since measurements began in 1890, with an acceleration since 1954.
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 the expected changes in radiative forcing values from the year 1750 to 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.
Climate change has led to extreme weather events in South Korea that affects: social, economy, industry, culture, and many other sectors. South Korea is experiencing changes in climate parameters. Such parameters include annual temperature, rainfall amounts, and precipitation.
India was ranked seventh among the list of countries most affected by climate change in 2019. India emits about 3 gigatonnes (Gt) CO2eq of greenhouse gases each year; about two and a half tons per person, which is less than the world average. The country emits 7% of global emissions, despite having 17% of the world population. The climate change performance index of India ranks eighth among 63 countries which account for 92% of all GHG emissions in the year 2021.
A climate target, climate goal or climate pledge is a measurable long-term commitment for climate policy and energy policy with the aim of limiting the climate change. Researchers within, among others, the UN climate panel have identified probable consequences of global warming for people and nature at different levels of warming. Based on this, politicians in a large number of countries have agreed on temperature targets for warming, which is the basis for scientifically calculated carbon budgets and ways to achieve these targets. This in turn forms the basis for politically decided global and national emission targets for greenhouse gases, targets for fossil-free energy production and efficient energy use, and for the extent of planned measures for climate change mitigation and adaptation.
