# Regarding various types of atmospheric pollution

Does all the car pollution (from about 150 million cars at least in the U.S. and a lot more in all of North America and the rest of the world) all the smoke-stack pollution of various factories and all the Airline pollution running day after day have a deleterious and damaging effect on the general atmosphere and, over time, the climate?

Given all the observed pollution that China has caused itself and some of the resulting weird weather events there this certainly seems to be evidence of the damaging effects of car and factory pollution. Has anyone calculated how much exhaust from cars is produced in one day on average in a 'moderate' sized city?

Of course it seems with all the increased oil production in the U.S. and elsewhere we, human beings are going to keep are love-affair with gas-powered cars for the next 200 or 300 years. That is if we don't use up all the oil and gas in the ground before then.

• What is defined as a 'moderate' sized city? – user889 Dec 24 '14 at 10:50
• What exactly do you mean by "pollution"? In particular, does CO$_2$ count as "pollution"? – David Hammen Dec 24 '14 at 13:28
• Do cars produce any type of pollution or emitted gases that might cause breathing problems? Can car emissions in gaseous form ever mix with precipitation and 'fall' to the ground? Is there anything even remotely dangerous to living things 'within' car emissions? – 201044 Dec 27 '14 at 3:40
• Did the United Nations leader at a press conference about the Human impact on climate change recently say we human beings are responsible for some of the 'dramatic' changes? Car and Factory pollution seem like good candidates. – 201044 Dec 27 '14 at 3:43
• Is there an endless supply of oil and gas ? – 201044 Jan 25 '15 at 5:40

As a USA resident, the EPA is the best place to start when wondering about the emissions inventory of atmospheric pollutants or pollutant precursors that affect the National Ambient Air Quality Standards (e.g. Particulate Matter, Carbon Monoxide, Sulfur Dioxide, Lead, Nitrogen Oxides, Volatile Organic Compounds). The EPA compiles a comprehensive emissions inventory of all criteria pollutants at the county level which is available in the National Emissions Inventory (compiled once every 3 years). You can see the summary of your county at http://www.epa.gov/air/emissions/where.htm. As for the effects of atmospheric pollution, it is important to consider the lifetime of said pollutants in the atmosphere in order to put their environmental impacts into perspective. For instance, the air pollutants covered by the National Ambient Air Quality Standards have immediate health effects when high concentrations are breathed in regularly. Both animals and plants are adversely affected by these irritating and sometimes toxic chemicals, but these pollutants are also reactive and do not last long in the atmosphere unless they are constantly being replenished (e.g. daily traffic). Air quality also impacts critical nitrogen loads on ecosystems and possible production of acid rain.

If you are interested in Greenhouse Gases (e.g. methane, carbon dioxide, CFCs, nitrous oxide), the EPA has a separate site for those emissions since they are not part of the same regulatory framework http://www.epa.gov/climatechange/ghgemissions/ . Greenhouse gases typically do not cause adverse health effects for plants or animals on land. However, they have long-term radiative effects (e.g. the greenhouse effect) because they stay in the atmosphere for many years and trap infrared light. These long-term radiative effects are what can change climate and consequently land cover. Furthermore, most of the excess carbon is absorbed by the ocean, which creates carbonic acid. Increased acidity of the ocean causes severe problems for marine ecosystems.

The EPA states that in 2012 the CO2 equivalent GHG emissions for the USA by sector was:

Electricity production (32% of 2012 greenhouse gas emissions) - Electricity production generates the largest share of greenhouse gas emissions. Over 70% of our electricity comes from burning fossil fuels, mostly coal and natural gas.

Transportation (28% of 2012 greenhouse gas emissions) - Greenhouse gas emissions from transportation primarily come from burning fossil fuel for our cars, trucks, ships, trains, and planes. Over 90% of the fuel used for transportation is petroleum based, which includes gasoline and diesel.

Industry (20% of 2012 greenhouse gas emissions) - Greenhouse gas emissions from industry primarily come from burning fossil fuels for energy as well as greenhouse gas emissions from certain chemical reactions necessary to produce goods from raw materials.

Commercial and Residential (10% of 2012 greenhouse gas emissions) - Greenhouse gas emissions from businesses and homes arise primarily from fossil fuels burned for heat, the use of certain products that contain greenhouse gases, and the handling of waste.

Agriculture (10% of 2012 greenhouse gas emissions) - Greenhouse gas emissions from agriculture come from livestock such as cows, agricultural soils, and rice production.

Land Use and Forestry (offset of 15% of 2012 greenhouse gas emissions) - Land areas can act as a sink (absorbing CO2 from the atmosphere) or a source of greenhouse gas emissions. In the United States, since 1990, managed forests and other lands have absorbed more CO2 from the atmosphere than they emit.

If we consider GHGs on a global level (see Global Carbon Project http://www.globalcarbonproject.org/carbonbudget/index.htm ) we can see how each sector has impacted the atmospheric concentration of CO2 over the past 143 yrs.

• All those sources include all pollution types in general. CO2 is a byproduct of any combustion. The problem with GHGs is that it is a global crisis in multiple biomes and climate regimes. Air quality pollution, with the exception of metals like lead, does not generally persist long enough to have any global impacts since the precursors/pollutants have long been chemically terminated or deposited on the regional landscape. Control technologies can limit air quality impacts, but you can't really "scrub" or "convert" GHG emissions, thus the importance of reducing or sequestering. – farrenthorpe Dec 27 '14 at 22:51
• GHGs are a global crisis because they stay in the atmosphere for many years and cause radiative effects (e.g. increased heat trapping) which leads to climate change (e.g. glaciers melting, sea levels rise, shifting ecosystems). Furthermore, most of the excess carbon is absorbed by the ocean, which creates carbonic acid. Increased acidity of the ocean does cause adverse health effects for plants and animals. – farrenthorpe Dec 28 '14 at 2:55
• Absolutely, any combustion source or depletion of forested land causes increased GHGs. However, the largest source of GHGs from humans is CO2 from power plants (primarily coal burning). I hightly suggest you check out globalcarbonproject.org if you are interested in source contributions of GHGs to the atmosphere. – farrenthorpe Dec 28 '14 at 3:04
• Actually I believe diesel powered freight (trucks + ships) has a higher GHG contribution than passenger cars. Thus many climate experts stress the importance of acquiring goods locally/regionally. – farrenthorpe Dec 28 '14 at 3:45
• @201044 Assuming you are talking about human-caused atmospheric pollution... Lead was a major problem years ago and is still re-suspended into the air in places like Los Angeles. Lead is an element that does not go away, but is toxic and linked to criminal rates. Sulfur dioxide was also a major problem for acid rain, but controls have lessened that considerably. Also, it's important to keep in mind that stratospheric ozone killers (e.g. CFCs) are also GHGs, so they have double impact. If you are a little more specific about the "problematic pollution" of interest, I could say more. – farrenthorpe Jan 20 '15 at 20:18