Earth & climate
Climate change
The Earth is measurably warming: where the extra CO₂ comes from, what it does and what we can do.
What you need first
You already know that act like a blanket around the Earth. For a good 150 years, we humans have been making this blanket thicker: we burn coal, oil and gas for electricity, heating and transport, and this releases extra CO₂. Today the consequences can not only be calculated but measured directly. The good news: we know the causes precisely, and that is why we also know the solutions.
What the measurements show
Weather stations, ships and satellites measure the temperature around the globe, and some data series go back well over 100 years. The result is clear: the global average temperature is now about 1.3 °C higher than in the period 1850 to 1900, when far less coal and oil was burned worldwide. That sounds like little, but for the climate system it is a lot. are melting and getting shorter year after year, sea level is currently rising by about 4 millimetres per year, and weather extremes such as heatwaves are becoming more frequent. At the same time, air bubbles trapped in Antarctic ice show that the CO₂ level of the air is higher than at any time in the last 800,000 years.
Burning it releases CO₂ that heats the planet. Global primary energy mix, rounded: 79% fossil, 11% renewable.
The solutions are on the table
Because the extra CO₂ comes mainly from burning coal, oil and gas, the most important solution starts exactly there: generating electricity and heat from renewable sources such as sun, wind and water, because nothing is burned for it and no extra CO₂ is released. The second big lever is efficiency, meaning achieving the same result with less energy, for example through well insulated houses, economical appliances and modern technology. Many countries are already expanding renewable energy rapidly, because new solar and wind farms now deliver the cheapest electricity in many places.
What you can do yourself
The big decisions are made by politics and industry, but your everyday life counts too. Short trips by bike or on foot instead of by car, switching off lights and devices nobody needs, repairing things and using them longer instead of buying new ones: every and every litre of fuel saved means less CO₂. And perhaps most importantly: understanding how the climate works and passing that knowledge on. That is exactly what you are doing right now.
Exercises
0 of 6 solvedTime to try it yourself. You can't break anything, every attempt counts.
Where does most of the extra CO₂ in the atmosphere come from?
Which of these energy sources is renewable?
In the period 1850 to 1900 the global average temperature was about 13.7 °C, today it is about 15.0 °C. By how many degrees has it risen?
Put the chain of climate change into the right order.
- 1The global average temperature rises.
- 2The greenhouse blanket around the Earth grows thicker.
- 3People burn coal, oil and gas.
- 4Extra CO₂ enters the atmosphere.
- 5Glaciers melt and sea level rises.
Due to warming, an Alpine glacier gets about 2 m shorter every year. How many metres does it lose in 15 years?
Match each measure to why it helps the climate.
Where this leads