Search results
Results from the WOW.Com Content Network
The concentrations of carbon dioxide in the atmosphere are expressed as parts per million by volume (abbreviated as ppmv, or ppm(v), or just ppm). To convert from the usual ppmv units to ppm mass (abbreviated as ppmm, or ppm(m)), multiply by the ratio of the molar mass of CO 2 to that of air, i.e. times 1.52 (44.01 divided by 28.96).
These six greenhouse gases are: carbon dioxide (CO 2), methane (CH 4), nitrous oxide (N 2 O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF 6). These greenhouse gases in the atmosphere constitute the "air pollution" that threatens both public health and welfare. 2) The Cause or Contribute Finding, in which the ...
The primary standard was set at 9 ppm averaged over an 8-hour period and 35 ppm over a 1-hour period. [10] The majority of CO emitted into the ambient air is from mobile sources. The EPA has reviewed and assessed the current scientific literature with respect to CO in 1979, 1984, 1991, and 1994. [11]
e. Air pollution is the contamination of air due to the presence of substances called pollutants in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. [ 1 ] It is also the contamination of the indoor or outdoor environment either by chemical, physical, or biological ...
The pCO 2 of Earth's atmosphere has risen from approximately 280 ppm (parts-per-million) to a mean 2019 value of 409.8 ppm as a result of anthropogenic release of carbon dioxide from fossil fuel burning. This is the highest atmospheric concentration to have existed on Earth for at least the last 800,000 years. [1]
Climate change was responsible for 3% of diarrhoea, 3% of malaria, and 3.8% of dengue fever deaths worldwide in 2004. [ 126 ] Total attributable mortality was about 0.2% of deaths in 2004; of these, 85% were child deaths. The effects of more frequent and extreme storms were excluded from this study.
Humans are the main indoor source of carbon dioxide (CO 2) in most buildings. Indoor CO 2 levels are an indicator of the adequacy of outdoor air ventilation relative to indoor occupant density and metabolic activity. Indoor CO 2 levels above 500 ppm can lead to higher blood pressure and heart rate, and increased peripheral blood circulation. [79]
The goal of the UNFCCC is to prevent dangerous human interference with the climate system. [373] As stated in the convention, this requires that greenhouse gas concentrations are stabilized in the atmosphere at a level where ecosystems can adapt naturally to climate change, food production is not threatened, and economic development can be ...