What is the greenhouse gas effect?

The greenhouse gas effect refers to the process by which certain gases in the Earth's atmosphere trap heat, preventing it from escaping back into space. This trapping of heat leads to an increase in the overall temperature of the Earth, which is crucial for maintaining the climate conditions that allow life to thrive.

Greenhouse gases, such as carbon dioxide, methane, and water vapor, absorb and re-radiate infrared radiation emitted by the Earth's surface. This creates a "blanket" effect, ensuring that the planet remains warm enough to sustain ecosystems, agriculture, and human activities. Without the greenhouse effect, the Earth would be much colder, and life as we know it would likely not exist.

The other choices do not accurately describe the greenhouse gas effect. The cooling of the Earth's surface suggests a decrease in temperature, which is contrary to what the greenhouse effect achieves. The increase of UV radiation speaks to a different atmospheric issue, primarily involving ozone depletion rather than heat trapping. The redistribution of atmospheric pressure could relate to various meteorological phenomena but does not specifically pertain to the greenhouse gas effect. Thus, the correct answer accurately reflects the primary function and significance of greenhouse gases in our climate system.