Urban ecology in temperate climates. Greenhouse gas emissions include those of carbon dioxide and methane from the combustion of fossil fuels to supply energy needed by vast urban metropolises. Other greenhouse gases include water vapor, and nitrous oxide. Increases in greenhouse gases due to urban transport, construction, industry and other demands have been correlated strongly with increase in temperature. Sources of methane are agricultural dairy cows and landfills. Processes related to urban areas result in the emission of numerous pollutants, which change corresponding nutrient cycles of carbon, sulfur, nitrogen, and other elements. Ecosystems in and around the urban center are especially influenced
Nitrous oxide more fuel by providing more oxygen than air alone, resulting in a more powerful combustion. The gas is not flammable at a low pressure/temperature, but it delivers more oxygen than atmospheric air by breaking down at elevated temperatures. Therefore, it often is mixed with another fuel that is easier to deflagrate. Nitrous oxide is a strong oxidant, roughly equivalent to hydrogen peroxide, and much stronger than oxygen gas. Nitrous oxide is stored as a compressed liquid; the evaporation and expansion of liquid nitrous oxide in the intake manifold causes a large drop in intake charge temperature, resulting in a denser