Greenhouse Gases and Atmosphere

Mars' atmosphere is composed of approximately 95% carbon dioxide, with about 2.7% nitrogen and 1.6% argon. The high concentration of CO2 creates a strong greenhouse effect, though the thin atmosphere overall prevents significant heat retention.

Paddy fields produce methane through anaerobic decomposition of organic matter in flooded soil conditions. Methanogenic archaea break down organic material in the oxygen-depleted environment, releasing methane (CH4) which is a potent greenhouse gas connected with global warming. While CO2 is also a greenhouse gas, paddy fields are specifically noted for methane emissions.

1, 2 and 4 only

Yes, it is the correct answer. Carbon dioxide, sulphur dioxide and methane are responsible for the greenhouse effect.

Carbon dioxide (CO2) is the primary greenhouse gas responsible for global warming, contributing about 76% of all greenhouse gas emissions from human activities. While CFCs are also greenhouse gases with high global warming potential, CO2 is by far the major one in terms of total emissions and overall impact.

Ozone (O3) has a dual nature - it is beneficial in the stratosphere where it forms the ozone layer that protects life from harmful UV radiation, but harmful at ground level where it is a toxic pollutant and component of smog. This Jekyll-and-Hyde character makes ozone unique among atmospheric gases. Oxygen is essential for life but not harmful in normal concentrations. Carbon dioxide and methane are primarily known as greenhouse gases without significant protective roles.

All three statements are consistent with WMO data from 2006. Statement I correctly notes greenhouse gases reached record levels with CO2 being the primary driver. Statement II accurately states CO2 and N2O concentrations were at recorded highs. Statement III is also correct as methane levels remained relatively stable between 2005 and 2006, unlike the other two gases which showed significant increases.

Methane is the primary component of natural gas, typically constituting 70-90% of its composition. Natural gas is formed from the decomposition of organic matter under high pressure and temperature conditions deep underground. While natural gas contains small amounts of ethane, propane, butane, and other hydrocarbons, methane remains the dominant and most significant component by volume.

Butane gas is the main constituent of cooking gas.

Methane (CH4) is the primary component of both biogas (50-75%) and natural gas (70-90%). Biogas is produced through anaerobic decomposition of organic matter, while natural gas is a fossil fuel extracted from underground reserves.

Sulphur trioxide (SO3) is not a greenhouse gas. It rapidly forms sulfate aerosols in the atmosphere which actually scatter solar radiation and contribute to cooling, not warming. Methane, nitrous oxide, and carbon dioxide are all well-established greenhouse gases with significant radiative forcing effects.

This is the correct option as nitrogen is not a greenhouse gas.

Carbon monoxide is considered to be a non-greenhouse gas. Though CO absorbs infrared rays, it is highly unstable and does not significantly contribute to greenhouse effect. 

Global warming is primarily caused by the increased concentration of greenhouse gases, with Carbon Dioxide (CO2) being the most significant contributor due to human activities like burning fossil fuels.