What is the ozone layer and why is it important? - teacher's notes

The ozone layer is a critical component of Earth's atmosphere that serves as a protective shield, absorbing the majority of the sun's harmful ultraviolet (UV) radiation. This layer, which is composed of ozone (O3) molecules, is situated in the stratosphere, a region of the atmosphere approximately 10 to 50 kilometers above the Earth's surface. The importance of the ozone layer lies in its ability to filter out UV-B radiation, which can cause skin cancer, cataracts, and impair the immune system in humans, as well as damage plant life and marine ecosystems. Understanding the ozone layer and its functions is essential for comprehending the broader implications of atmospheric changes on our planet's health and the well-being of all living organisms.

Due to certain human-made chemicals, particularly chlorofluorocarbons (CFCs), the ozone layer has been under threat, leading to the creation of an 'ozone hole' over the Antarctic. This unit is designed to help pupils grasp the significance of the ozone layer and the reasons behind its vulnerability. Through the creation of diagrams, students will visually represent the issues affecting the ozone layer. Additionally, they will explore recent developments by watching an online resource that illustrates the reduction in the size of the ozone hole, highlighting the positive impact of global environmental policies and efforts to phase out ozone-depleting substances. The unit aims to raise awareness among students about the importance of the ozone layer and the ongoing challenges in preserving it for future generations.