Causes of global warming

There are various factors that cause global warming. Firstly, some scientists believe that global warming is caused by natural factors such as:
''Changes in the Earth's orbit around the sun
Explosions on the sun (sun spot)
volcanic emissions
changes in the Earth's orientation toward the sun
As the world evolves, changes in the earth environment affect climate in different ways. For example, volcanic eruptions can cause temperature to decrease because the smoke can act like umbrella and stop sunlight .also any slight change in the Earth's orbit could cause the earth to move closer or away from the sun. This will radically change earth temperature because it will become closer to sun (source of heat).
Human activities cause:
It may seem hard to believe that people can actually change the earth climate. But scientists think that people lead to an increase in the mount of greenhouse gases. After the industrial revolution, we began altering our climate and environmental through agricultural and industrial activities.
Before this revolution human activities release few gases but now through population growth, fossil fuel burning and deforestation .we are affecting the mixture of gases in the atmosphere .also the trash that we send to the landfills produce a greenhouse gas called methane. On the other hand, there are many human activities that cause global warming such as automobiles and coal-burning power plants. These activities produce greenhouse gases which are the main reason that made the planet warm up. Carbon dioxide (CO2) is the most significant green houses gas because factory smokestacks, automobile and other human activities produce 22 billion tons of Carbon dioxide in to the earth's atmosphere each year , while animal agriculture , manure and other sources produce 250 million tons of methane (Ch4) each year.
Greenhouse gases:
Many chemical compounds found in the earths atmosphere act as “greenhouse gases” .these gases permit sunlight to enter the atmosphere freely ,when sunlight strikes the earth surface .some of it reflected back to space and some of them is absorbed and trapped in the atmosphere .over time the temperature of the earth surface remain constant . But later the amount of greenhouse gases increase in air that lead to trap more heat in earth atmosphere. And some of this gases which caused by human activities are carbon dioxide, methane, cfcs nitrous oxide and ozone. This gases have special properties .they are transparent to visible wavelengths of light and they have strong absorption regions called bands .our greenhouse gases emission come mostly from energy use . These are driven largely by economic growth, fuel used for electricity.