Other Factors Affecting The Greenhouse Effect

-

Aerosols, also known as particulates, are airborne particles that absorb, scatter, and reflect radiation back into space. Clouds, windblown dust, and particles that can be traced to erupting volcanoes are examples of natural aerosols. Human activities, including the burning of fossil fuels and slash-and-burn farming techniques used to clear forestland, contribute additional aerosols to the atmosphere. Although aerosols are not considered a heat-trapping greenhouse gas, they do affect the transfer of heat energy radiated from the Earth to space. The effect of aerosols on climate change is still debated, but scientists believe that light-colored aerosols cool the Earth’s surface, while dark aerosols like soot actually warm the atmosphere. The increase in global temperature in the last century is lower than many scientists predicted when only taking into account increasing levels of carbon dioxide, methane, nitrous oxide, and fluorinated compounds. Some scientists believe that aerosol cooling may be the cause of this unexpectedly reduced warming.

However, scientists do not expect that aerosols will ever play a significant role in offsetting global warming. As pollutants, aerosols typically pose a health threat, and the manufacturing or agricultural processes that produce them are subject to air-pollution control efforts. As a result, scientists do not expect aerosols to increase as fast as other greenhouse gases in the 21st century.

Comments

Post a Comment

Popular posts from this blog

Types of Pollution

-
Pollution exists in many forms and affects many different aspects of Earth’s environment. Point-source pollution comes from specific, localized, and identifiable sources, such as sewage pipelines or industrial smokestacks. Nonpoint-source pollution comes from dispersed or uncontained sources, such as contaminated water runoff from urban areas or automobile emissions. The effects of these pollutants may be immediate or delayed. Primary effects of pollution occur immediately after contamination occurs, such as the death of marine plants and wildlife after an oil spill at sea. Secondary effects may be delayed or may persist in the environment into the future, perhaps going unnoticed for many years. DDT, a nondegradable compound, seldom poisons birds immediately, but gradually accumulates in their bodies. Birds with high concentrations of this pesticide lay thin-shelled eggs that fail to hatch or produce deformed offspring. Types of Pollution: Air Pollution Water Pollution Soil Pollution
Read more

Air Pollution

-
Air Pollution, addition of harmful substances to the atmosphere resulting in damage to the environment, human health, and quality of life. One of many forms of pollution , air pollution occurs inside homes, schools, and offices; in cities; across continents; and even globally. Air pollution makes people sick—it causes breathing problems and promotes cancer—and it harms plants, animals, and the ecosystems in which they live. Some air pollutants return to Earth in the form of acid rain and snow, which corrode statues and buildings, damage crops and forests, and make lakes and streams unsuitable for fish and other plant and animal life. Pollution is changing Earth’s atmosphere so that it lets in more harmful radiation from the Sun. At the same time, our polluted atmosphere is becoming a better insulator, preventing heat from escaping back into space and leading to a rise in global average temperatures. Scientists predict that the temperature increase, referred to as global warming , will
Read more

Changes to Earth's Surface: Weathering

-
Weathering is the breakdown of rock at and near the surface of Earth. Most rocks originally formed in a hot, high-pressure environment below the surface where there was little exposure to water. Once the rocks reached Earth’s surface, however, they were subjected to temperature changes and exposed to water. When rocks are subjected to these kinds of surface conditions, the minerals they contain tend to change. These changes constitute the process of weathering. There are two types of weathering: physical weathering and chemical weathering. Physical weathering involves a decrease in the size of rock material. Freezing and thawing of water in rock cavities, for example, splits rock into small pieces because water expands when it freezes. Chemical weathering involves a chemical change in the composition of rock. For example, feldspar, a common mineral in granite and other rocks, reacts with water to form clay minerals, resulting in a new substance with totally different properties than th
Read more