In environmental science, which type of gases absorb long wavelength (infrared) radiation emitted by the Earth and then re emit it back towards the surface, contributing to the greenhouse effect?

Introduction / Context:
The greenhouse effect is a key concept in climate science and environmental studies. It describes the process by which certain gases in the atmosphere trap heat, keeping the planet warmer than it would be without them. These gases absorb long wavelength infrared radiation emitted from the Earth surface and then re emit some of this energy back towards the surface. This question asks for the name given to such gases, which include well known examples like carbon dioxide and methane.

Given Data / Assumptions:

• The question refers to gases that absorb infrared radiation from the Earth and re emit it towards the Earth.
• Options mention carbon dioxide, methane, greenhouse gases as a category, and ozone.
• We assume a basic understanding of the greenhouse effect in the context of global warming and climate change.
• The question seeks the general name of the group of gases, not just one example.

Concept / Approach:
Greenhouse gases are those atmospheric gases that are transparent to incoming short wave solar radiation but absorb and re emit outgoing long wave infrared radiation from the Earth. This group includes carbon dioxide, methane, nitrous oxide, water vapour, and some industrial gases. While carbon dioxide and methane are important examples, the term greenhouse gases collectively covers all such heat trapping gases. Ozone has complex roles in the atmosphere, especially in the stratospheric ozone layer, but the question is more general and focuses on the key definition describing the greenhouse effect. Therefore, the correct answer is greenhouse gases such as carbon dioxide and methane.

Step-by-Step Solution:
Step 1: Identify that the gases described absorb infrared radiation emitted by the Earth and re emit it back towards the surface. Step 2: Recall that this behaviour is characteristic of greenhouse gases, which produce the greenhouse effect. Step 3: Recognise carbon dioxide and methane as classic examples of greenhouse gases that contribute significantly to global warming. Step 4: Note that the question is asking for the general category name rather than just one specific gas. Step 5: Select the option that explicitly refers to greenhouse gases such as carbon dioxide and methane as the correct one.

Verification / Alternative check:
Environmental science texts define greenhouse gases as those atmospheric constituents that absorb and emit infrared radiation within the wavelength range emitted by Earth surface. Carbon dioxide and methane are consistently listed as major greenhouse gases. While both carbon dioxide and methane can be individually named, the broader category term greenhouse gases is used in discussions about climate change and international agreements. Ozone does absorb ultraviolet radiation and contributes to greenhouse warming in some layers, but it is usually treated in more specialised contexts. Therefore, the general description in the question matches the standard definition of greenhouse gases.

Why Other Options Are Wrong:
Carbon dioxide alone is only one example of a greenhouse gas and does not represent the entire category by itself. Methane is another important example but again is only one member of the group. Ozone is significant in absorbing harmful ultraviolet radiation in the stratosphere and also behaves as a greenhouse gas in some contexts, but the option that mentions only ozone does not describe the full set of gases discussed in the question. The option referring to greenhouse gases explicitly includes carbon dioxide and methane and best matches the general description provided.

Common Pitfalls:
Students sometimes focus on a single gas, usually carbon dioxide, because it is widely discussed in media, and overlook that several gases together contribute to the greenhouse effect. Another pitfall is to confuse the role of ozone in protecting against ultraviolet radiation with the broader greenhouse gas category. To avoid such errors, remember that the term greenhouse gases collectively refers to all heat trapping gases, with carbon dioxide and methane being prominent examples. This understanding helps in interpreting many exam questions on climate and environmental science correctly.

Final Answer:
The gases that absorb long wave radiation and re emit it towards Earth are greenhouse gases such as carbon dioxide and methane.