Is there any difference between atmospheric and barometric pressure?
The amount of force exerted over a surface area, by the weight of air molecules above it is known as atmospheric pressure. As elevation increases, fewer air molecules are present.Therefore, atmospheric pressure always decreases with increasing height. A column of air in cross section, measured from sea level to the top of the atmosphere, would weigh approximately 14.7 pounds per square inch. Barometric pressure is the same as Atmospheric Pressure

How is humidity different from absolute humidity?
The amount of water vapor present in the air is known as humidity. The higher the temperature, the greater the number of water molecules the air can hold. Humidity is also commonly used to describe the relative humidity. Absolute humidity is the mass of water vapor present per unit volume of air.

Is thermometer and barometer the same thing?
Thermometer is an instrument for measuring temperature consisting typically of a glass bulb attached to a fine tube of glass with a numbered scale and containing a liquid that is sealed in and rises and falls with changes of temperature. A barometer on the other hand is used to measure atmospheric pressure. A typical barometer employs a mercury-filled glass tube, sealed at one end with a mercury reservoir at the other end. The mercury then adjusts between the tube and the reservoir to reflect atmospheric pressure. Low pressure will cause the mercury to drop in the tube. High pressure forces the mercury to rise in the column.

How does one differentiate between condensation and saturation?
The process by which water vapor changes into water droplets and clouds is known as Condensation, while saturation means the maximum amount of water vapor a mass of air can hold at its current temperature.

What role does ozone play in global warming?
Usually found in the stratosphere, a colorless gas and a form of oxygen which is responsible for filtering out much of the sun's ultraviolet radiation and thus restricting them to enter the earth's atmosphere.

What is green house effect?
Greenhouse effect is the progressive, gradual warming of the earth's atmospheric temperature, caused by the insulating effect of carbon dioxide and other greenhouse gases that have proportionately increased in the atmosphere. The greenhouse effect disturbs the way the Earth’s climate maintains the balance between incoming and outgoing energy by allowing short-wave radiations from the sun to penetrate through to warm the earth, but preventing the resulting long-wave radiations from escaping back into the atmosphere. The main culprits to the greenhouse effect are greenhouse gases. The main greenhouse gases are not the major constituents of the atmosphere like nitrogen and oxygen but water vapor, carbon dioxide, methane, nitrous oxide, and chlorofluorocarbons, CFCs (organic compounds that contain carbon, chlorine, and fluorine atoms). Increase in concentrations of the latter four gases have been linked to emissions from human activity. (Most of these gases are a direct or indirect result of fossil fuel burning).