Sentences with phrase «urban pollution concentrations»

Urban pollution concentrations depend on the magnitude of local emissions sources and the prevailing meteorological ventilation of the area — i.e., the height of the atmospheric layer through which the pollutants are being mixed and the average wind speed through that layer.

Not exact matches

In a typical urban area with a high level of background air pollution — for example, around 15 micrograms of fine particulate matter (PM2.5) per cubic metre, or a nitrogen dioxide concentration around 33 micrograms per cubic metre — an extra 300 trees per square kilometre was associated with around 50 fewer emergency asthma cases per 100,000 residents over the 15 year study period.

Gary Cohen, president and founder of the Massachusetts - based nonprofit Health Care Without Harm, said in a telephone interview that the risks of climate change to both the health of U.S. citizens and the U.S. health care delivery system is profound, particularly in urban areas, where warming average temperatures are exacerbated by the heat island effect and high concentrations of other air pollution like ozone and particulate matter.

Health benefits may include: physical activity from walking and cycling, which can help prevent heart disease, some cancers, type 2 diabetes, and some obesity - related risks; lower urban air pollution concentrations; lower rates of traffic injury risks for users of dedicated bicycle and pedestrian networks; and less noise stress.

High levels of public transport density are usually accompanied by higher levels of traffic - related noise and air pollution, especially in urban environments typified by a concentration of tall buildings.54 Both excessive traffic - related noise and air pollution have been linked to stress, inability to psychologically restore and depression.55 56 One of the main features included in the measure of street connectivity used in this study was the presence of bridges, overpasses or tunnels.