Environmental Science
Climate Change
Quick fact
The Earth's average temperature has risen by about 1.2°C since the late 19th century, with most of the warming occurring in the last 40 years, primarily due to human-emitted greenhouse gases.
Why this is interesting
You've heard about record heatwaves and melting ice caps, but why is the planet heating up—and is this really different from natural weather cycles?
Read the full explanation
Understanding Climate Change
Imagine Earth wrapped in a blanket that keeps it warm enough for life. This blanket is the atmosphere, which contains greenhouse gases like carbon dioxide and methane. They trap some of the Sun's heat. But since the Industrial Revolution, humans have been burning large amounts of fossil fuels (coal, oil, gas), releasing extra CO₂ into the atmosphere. This thickens the blanket, trapping more heat and causing the planet to warm. This warming disrupts weather patterns, melts glaciers, and raises sea levels. Climate change is not just about temperature highs—it shifts the entire climate system, making some regions drier, others wetter, and storms more intense.
A deeper explanation
The mechanism behind climate change lies in the enhanced greenhouse effect. Sunlight reaches Earth and warms its surface. The Earth then radiates infrared heat back toward space. Greenhouse gases (GHGs) absorb some of this outgoing radiation and re-emit it in all directions, including back to the surface. This natural greenhouse effect maintains a livable temperature. Human activities, especially burning fossil fuels, deforestation, and industrial processes, have significantly increased the concentration of GHGs—CO₂ has risen from about 280 ppm in pre-industrial times to over 420 ppm today. This additional absorption traps more heat, raising average global temperature. Climate feedback loops amplify the effect: for example, as ice melts, less sunlight is reflected (albedo effect), leading to more warming and further ice loss. Climate change matters because it affects every aspect of life—food production, water availability, health, and ecosystems. Understanding why it happens helps us design solutions like renewable energy, carbon capture, and conservation policies.