Global Warming

Key Stage 4

Meaning

Global warming is a scientific observation that the average temperature of the Earth is increasing.

About Global Warming

Global warming happens naturally. However, scientists theorise the current trend of global warming is being caused by human activity on Earth. This theory is known as Anthropogenic Global Warming.

Global warming can be caused by increased concentrations of greenhouse gases such as Carbon Dioxide and Methane which are being produced in larger quantities currently due to human activity.

The exact effects of global warming are unknown. However, it is likely to affect different climates around the Earth in different ways. This is known as climate change.

climate change caused by global warming can cause habitat destruction due to changes in weather patterns in many different ecosystems possibly causing drought, flooding, temperature rises or temperature falls depending on the location.

Some scientists are investigating ways to slow or reverse global warming to prevent climate change. These methods are known as geoengineering and they are an attempt to control the average temperature of the Earth's surface.

Uncertainties about Global Warming

While the average temperature of Earth seems to be increasing there are some uncertainties in the measurements taken.

• Accurate temperature records from thermometers only go back around 160 years.
• Thermometers that were once in rural areas are now surrounded by buildings which causes a 'heat island effect' which makes the readings unreliable as there is another variable which has affected their temperature readings.
• Old thermometers were far less accurate than modern thermometers. Some scientists believe this is what caused an apparent halt in global warming over the last decade and in fact global warming didn't stop, we just got better thermometers.