Final answer:
The greenhouse effect is a natural process that warms Earth's surface, and is vital for life. The enhanced greenhouse effect, due to human activities, leads to additional warming, contributing to global warming and climate change.
Step-by-step explanation:
The greenhouse effect is a natural process that warms the Earth’s surface. When the Sun’s energy reaches the Earth, some of it is reflected back to space and the rest is absorbed and re-radiated by greenhouse gases. The absorbed energy warms the Earth’s surface, maintaining the planet’s temperature at a level capable of supporting life.
The enhanced greenhouse effect, however, refers to the additional warming that results from increased levels of greenhouse gases due to human activities, such as burning fossil fuels and deforestation. This results in more heat being trapped and an increase in Earth’s average temperature, contributing to global warming and climate change.
Both versions of the greenhouse effect involve greenhouse gases like carbon dioxide (CO₂) and water vapor (H₂O) absorbing infrared radiation, but their key difference lies in the extent of the effect. While both block infrared radiation, preventing heat from escaping to space, the similarity ends there as the enhanced effect leads to a significant increase in global temperatures due to elevated concentrations of greenhouse gases. This is why enhanced greenhouse effect does not result in a net zero temperature change but rather, a warming climate.
Greenhouse gases allow sunlight to enter the atmosphere freely. When sunlight strikes the Earth’s surface, some of it is reflected back towards space as infrared radiation. Greenhouse gases trap some of this infrared radiation and radiate it all directions, including back to the Earth’s surface. This is what keeps the Earth’s surface much warmer than it would otherwise be without these gases.