Commuting is periodically recurring travel between one's place of residence and place of work or study, where the traveler leaves the boundary of their home community. By extension, it can sometimes be any regular or often repeated travel between locations, even when not work-related. The modes of travel, time taken and distance traveled in commuting varies widely across the globe. Most people in least-developed countries continue to walk to work, as the ancestors of all people did until the nineteenth century. The cheapest method of commuting after walking is usually by bicycle, so this is common in low-income countries, but is also increasingly practised by people in wealthier countries for environmental and health reasons. In middle-income countries, motorcycle commuting is very common. The next technology adopted as countries develop is more dependent on location: in more populous, older cities, especially in Eurasia mass transit predominates, while in smaller, younger cities, and large parts of North America and Australasia, communing by personal automobile is more common. A small number of very wealthy people, and those working in remote locations across the world, also commute by air travel, often for a week or more at a time rather the more typical daily commute. Transportation links that enable commuting also impact the physical layout of cities and regions, allowing a distinction to arise between mostly-residential suburbs and the more economically-focused urban core of a city, but the specifics of how that distinction is realized remain drastically different between societies, with Eurasian "suburbs" often being more densely populated than North American "urban cores".
Fuel efficiency is a form of thermal efficiency, meaning the ratio of effort to result of a process that converts chemical potential energy contained in a carrier (fuel) into kinetic energy or work. Overall fuel efficiency may vary per device, which in turn may vary per application, and this spectrum of variance is often illustrated as a continuous energy profile. Non-transportation applications, such as industry, benefit from increased fuel efficiency, especially fossil fuel power plants or industries dealing with combustion, such as ammonia production during the Haber process.
The California Air Resources Board is the "clean air agency" in the government of California. Established in 1967 when then-governor Ronald Reagan signed the Mulford-Carrell Act, combining the Bureau of Air Sanitation and the Motor Vehicle Pollution Control Board, CARB is a department within the cabinet-level California Environmental Protection Agency.
The Corporate Average Fuel Economy (CAFE) standards are regulations in the United States, first enacted by the United States Congress in 1975, after the 1973–74 Arab Oil Embargo, to improve the average fuel economy of cars and light trucks produced for sale in the United States.
Exhaust gas or flue gas is emitted as a result of the combustion of fuels such as natural gas, gasoline (petrol), diesel fuel, fuel oil, biodiesel blends, or coal. According to the type of engine, it is discharged into the atmosphere through an exhaust pipe, flue gas stack, or propelling nozzle. It often disperses downwind in a pattern called an exhaust plume.
Sustainable transport refers to the broad subject of transport that is sustainable in the senses of social, environmental and climate impacts. Components for evaluating sustainability include the particular vehicles used for road, water or air transport; the source of energy; and the infrastructure used to accommodate the transport. Transport operations and logistics as well as transit-oriented development are also involved in evaluation. Transportation sustainability is largely being measured by transportation system effectiveness and efficiency as well as the environmental and climate impacts of the system.
A green vehicle, clean vehicle, eco-friendly vehicle or environmentally friendly vehicle is a road motor vehicle that produces less harmful impacts to the environment than comparable conventional internal combustion engine vehicles running on gasoline or diesel, or one that uses certain alternative fuels. Presently, in some countries the term is used for any vehicle complying or surpassing the more stringent European emission standards, or California's zero-emissions vehicle standards, or the low-carbon fuel standards enacted in several countries.
A carbon footprint is the total greenhouse gas (GHG) emissions caused by an individual, event, organization, service, place or product, expressed as carbon dioxide equivalent. Greenhouse gases, including the carbon-containing gases carbon dioxide and methane, can be emitted through the burning of fossil fuels, land clearance and the production and consumption of food, manufactured goods, materials, wood, roads, buildings, transportation and other services. The term was popularized by a $250 million advertising campaign by the oil and gas company BP in an attempt to move public attention away from restricting the activities of fossil fuel companies and onto individual responsibility for solving climate change.
Mode of transport is a term used to distinguish between different ways of transportation or transporting people or goods. The different modes of transport are air, water, and land transport, which includes Rails or railways, road and off-road transport. Other modes also exist, including pipelines, cable transport, and space transport. Human-powered transport and animal-powered transport are sometimes regarded as their own mode, but never fall into the other categories. In general, transportation is used for moving of people, animals, and other goods from one place to another. Means of transport, on the other hand, refers to the transport facilities used to carry people or cargo ,according to the chosen mode. Each mode of transport has a fundamentally different technological solution, and some require a separate environment. Each mode has its own infrastructure, vehicles, transport operators and operations.
Individual and political action on climate change can take many forms. Many actions aim to build social and political support to limit and reduce the concentration of greenhouse gases (GHGs) in the atmosphere, with the goal of mitigating climate change. Other actions seek to address the ethical and moral aspects of climate justice, especially with regard to the anticipated unequal impacts of climate change adaptation.
The fuel economy of an automobile relates distance traveled by a vehicle and the amount of fuel consumed. Consumption can be expressed in terms of volume of fuel to travel a distance, or the distance travelled per unit volume of fuel consumed. Since fuel consumption of vehicles is a significant factor in air pollution, and since importation of motor fuel can be a large part of a nation's foreign trade, many countries impose requirements for fuel economy. Different methods are used to approximate the actual performance of the vehicle. The energy in fuel is required to overcome various losses encountered while propelling the vehicle, and in providing power to vehicle systems such as ignition or air conditioning. Various strategies can be employed to reduce losses at each of the conversions between the chemical energy in the fuel and the kinetic energy of the vehicle. Driver behavior can affect fuel economy; maneuvers such as sudden acceleration and heavy braking waste energy.
Like other emissions resulting from fossil fuel combustion, aircraft engines produce gases, noise, and particulates, raising environmental concerns over their global impact and their local air quality effect. Jet airliners contribute to climate change by emitting carbon dioxide, the best understood greenhouse gas, and, with less scientific understanding, nitrogen oxides, contrails and particulates. Their radiative forcing is estimated at 1.3–1.4 that of CO
2 alone, excluding induced cirrus cloud with a very low level of scientific understanding. In 2018, global commercial operations generated 2.4% of all CO
2 emissions.
The energy efficiency in transport is the useful travelled distance, of passengers, goods or any type of load; divided by the total energy put into the transport propulsion means. The energy input might be rendered in several different types depending on the type of propulsion, and normally such energy is presented in liquid fuels, electrical energy or food energy. The energy efficiency is also occasionally known as energy intensity. The inverse of the energy efficiency in transport, is the energy consumption in transport.
The United States produced 6.6 billion metric tons of carbon dioxide equivalent greenhouse gas (GHG) emissions in 2019, 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 400 billion metric tons, more than any other country. This is over 15 tonnes per person and, amongst the top ten emitters, is the second highest country by greenhouse gas emissions per person after Canada. Because coal-fired power stations are gradually shutting down, in the 2010s emissions from electricity generation fell to second place behind transportation which is now the largest single source. In 2019, 29% of the GHG emissions of the United States were from transportation, 25% from electricity, 23% from industry, 13% from commercial and residential buildings and 10% from agriculture.
The Global Warming Pollution Reduction Act of 2007 (S. 309) was a bill proposed to amend the 1963 Clean Air Act, a bill that aimed to reduce emissions of carbon dioxide (CO2). A U.S. Senator, Bernie Sanders (I-VT), introduced the resolution in the 110th United States Congress on January 16, 2007. The bill was referred to the Senate Committee on Environment and Public Works but was not enacted into law.
United States vehicle emission standards are set through a combination of legislative mandates enacted by Congress through Clean Air Act (CAA) amendments of 1970 and beyond, and executive regulations managed nationally by the Environmental Protection Agency (EPA), and more recently along with the National Highway Traffic Safety Administration (NHTSA). These standard cover common motor vehicle air pollution, including carbon monoxide, nitrogen oxides, and particulate emissions, and newer versions have incorporated fuel economy standards.
Active mobility, active travel, active transport or active transportation is the transport of people or goods, through non-motorized means, based around human physical activity. The best-known forms of active mobility are walking and cycling, though other modes include running, rowing, skateboarding, kick scooters and roller skates. Due to its prevalence, cycling is sometimes considered separately from the other forms of active mobility.
The environmental impact of shipping includes air pollution, water pollution, acoustic, and oil pollution. Ships are responsible for more than 18 percent of some air pollutants.
Mobile source air pollution includes any air pollution emitted by motor vehicles, airplanes, locomotives, and other engines and equipment that can be moved from one location to another. Many of these pollutants contribute to environmental degradation and have negative effects on human health. To prevent unnecessary damage to human health and the environment, environmental regulatory agencies such as the U.S. Environmental Protection Agency have established policies to minimize air pollution from mobile sources. Similar agencies exist at the state level. Due to the large number of mobile sources of air pollution, and their ability to move from one location to another, mobile sources are regulated differently from stationary sources, such as power plants. Instead of monitoring individual emitters, such as an individual vehicle, mobile sources are often regulated more broadly through design and fuel standards. Examples of this include corporate average fuel economy standards and laws that ban leaded gasoline in the United States. The increase in the number of motor vehicles driven in the U.S. has made efforts to limit mobile source pollution challenging. As a result, there have been a number of different regulatory instruments implemented to reach the desired emissions goals.
Electric cars have different environmental impacts compared to conventional internal combustion engine vehicles (ICEVs). While aspects of their production can induce similar, less or alternative environmental impacts, some models produce little or no tailpipe emissions, and some have the potential to reduce dependence on petroleum and greenhouse gas emissions, depending on the source of electricity used to charge them, and health effects from air pollution. Electric motors are significantly more efficient than internal combustion engines and thus, even accounting for typical power plan efficiencies and distribution losses, less energy is required to operate an EV. Producing batteries for electric cars requires additional resources and energy, so they may have a larger environmental footprint from the production phase. EVs also generate different impacts in their operation and maintenance. EVs are typically heavier and could produce more tire, brake, and road dust, but their regenerative braking could reduce brake particulate pollution. EVs are mechanically simpler, which reduces the use and disposal of engine oil.
