Causes For Global Warming

Carbon dioxide during the last 400,000 years and the rapid rise since the Industrial Revolution; changes in the Earth's orbit around the Sun, known as Milankovitch cycles, are believed to be the pacemaker of the 100,000 year ice age cycle.

Recent increases in atmospheric carbon dioxide (CO2). The monthly CO2 measurements display small seasonal oscillations in an overall yearly uptrend; each year's maximum is reached during the Northern Hemisphere's late spring, and declines during the Northern Hemisphere growing season as plants remove some CO2 from the atmosphere.
The Earth's climate changes in response to external forcing, including variations in its orbit around the sun (orbital forcing), volcanic eruptions, and atmospheric greenhouse gas concentrations. The detailed causes of the recent warming remain an active field of research, but the scientific consensus identifies elevated levels of greenhouse gases due to human activity as the main influence. This attribution is clearest for the most recent 50 years, for which the most detailed data are available. Some other hypotheses departing from the consensus view have been suggested to explain the observed increase in mean global temperature. One such hypothesis proposes that warming may be the result of variations in solar activity.
None of the effects of forcing are instantaneous. The thermal inertia of the Earth's oceans and slow responses of other indirect effects mean that the Earth's current climate is not in equilibrium with the forcing imposed. Climate commitment studies indicate that even if greenhouse gases were stabilized at 2000 levels, a further warming of about 0.5 °C (0.9 °F) would still occur.

Causes For Pollution

Motor vehicle emissions are one of the leading causes of air pollution. China, United States, Russia, Mexico, and Japan are the world leaders in air pollution emissions; however, Canada is the number two country, ranked per capita. Principal stationary pollution sources include chemical plants, coal-fired power plants, oil refineries, petrochemical plants, nuclear waste disposal activity, incinerators, large livestock farms (dairy cows, pigs, poultry, etc.), PVC factories, metals production factories, plastics factories, and other heavy industry.
Some of the more common soil contaminants are chlorinated hydrocarbons (CFH), heavy metals (such as chromium, cadmium--found in rechargeable batteries, and lead--found in lead paint, aviation fuel and still in some countries, gasoline), MTBE, zinc, arsenic and benzene. Ordinary municipal landfills are the source of many chemical substances entering the soil environment (and often groundwater), emanating from the wide variety of refuse accepted, especially substances illegally discarded there, or from pre-1970 landfills that may have been subject to little control in the U.S. or EU. There have also been some unusual releases of polychlorinated dibenzodioxins, commonly called dioxins for simplicity, such as TCDD.
Pollution can also be the consequence of a natural disaster. For example, hurricanes often involve water contamination from sewage, and petrochemical spills from ruptured boats or automobiles. Larger scale and environmental damage is not uncommon when coastal oil rigs or refineries are involved. Some sources of pollution, such as nuclear power plants or oil tankers, can produce widespread and potentially hazardous releases when accidents occur.
In the case of noise pollution the dominant source class is the motor vehicle, producing about ninety percent of all unwanted noise worldwide.

Causes For Litter

According to Georgia's Litter. It Costs You campaign, the most commonly found items in roadside litter clean-ups are cigarette butts, snack/take out packaging, plastic, and paper. In a statewide roadside litter survey, two thirds of the litter found along roadways was the result of negligent litter; litter from trash-hauling vehicles, unsecured loads, or construction sites. Some commonly-blamed groups are customers of fast food outlets, smokers and young adults. Studies show that areas which are allowed to remain dirty are prone to becoming dirtier, i.e. litter gives "permission" to litter. There are also natural causes such as high winds disturbing litter containers. Litter can be a result of lack of education.
Francis McAndrew's Environmental Psychology, a textbook used by scholars to explain littering by humans, reports that women, youth, rural dwellers and live-alone persons litter more than men, seniors, urban dwellers and multi-person households. Picnickers, hunters, fishermen, campers, motorboaters, water skiers, careless pedestrians, motorists, truck drivers, construction and loading dock workers, are prime litter providers. Prototype research by the state of Texas "profiled" litterers being males, youth under age 25, non-whites, smokers, and frequenters to bars, parties and fast food restaurants. These research results are replicated by many state governments to tailor and enforce litter eradication programs.

Many factors contribute to why people choose to litter, according to McAndrew. He argues the “presence of other litter” is a powerful instigator. Studies confirm that litter begets litter. A “disconnect from reality”-—apathy-—is a second dynamic. Research by Keep America Beautiful in 1999 found 75 percent of Americans admitted to littering in the last five years, yet 99 percent of the same surveyed individuals admitted they enjoyed a clean environment. Negligent, lax law enforcement contributes significantly to this disconnect. Generally, violations must be witnessed to be legally pursued. Inconvenience is another influence. Entitlement is a fourth dynamic to why people litter. A fifth factor is class alienation leading to poor education of individuals. “Dumping is a social activity we learn from...parents and pass on unconsciously to...children.” Litterers are “raised badly” by parents--“…vandals with little sense [of the] damage they do.” The temptation to litter can be motivated “by greed” and ignorance about the law and its actual enforcement, according to a Federal document by The United States Department of Justice, mentioning the criminal intent of suspects arrested for illegal waste disposal, reassured by lax law enforcement. Finally, governmental neglect influences littering. “Government… [has followed] the path of least resistance…[in addressing] externalities…that may pose…health threat[s]…to nearby communities.” Culturally biased indifference by public servants causes some communities to have persistent dumping problems