What is climate change?

The term climate change refers to global-scale warming of climate, which is caused by the increasing amount of carbon dioxide, methane and other greenhouse gases in the atmosphere. The most significant greenhouse gas is carbon dioxide. It is produced, in particular, by the use of coal, oil and natural gas. In the Helsinki Metropolitan Area, the largest sources of greenhouse gases are heating, electricity consumption and traffic.

The atmosphere is like the glass ceiling of a greenhouse – it warms the earth. Similar to the glass ceiling, the greenhouse gases allow the sun’s radiation to pass through to the earth. However, they do not let all the warmth radiating back from the earth out into space.

At the moment, the amount of greenhouse gases in the atmosphere is increasing steeply, which is why a larger and larger share of the sun’s radiation remains on earth, warming it up. This ability of the green-house’s glass ceiling to act as a selective filter – allowing the sun’s radiation in, but not letting all heat radiation back through – is called the greenhouse effect. Climate change is caused by the increasing greenhouse effect.

In little over a hundred years, the average temperature of earth has risen almost by one degree, and the consequences are already visible. Due to climate change, the sea level rises, rains and floods increase and, on the other hand, droughts become more common. As the climate warms further, the risks contin-ue to grow. Access to clean water and food production on earth are at risk and biodiversity is suffering. Vulnerability to extreme weather conditions increases in urban areas.

​We can mitigate ​climate change

It is no longer possible to completely prevent climate change. We will have to adapt to global warming and its consequences. However, it is possible to mitigate climate change. The most important measure of mitigating climate change is to cut down on the use of fossil fuels and protect the carbon sinks, such as forests. The essential factors in decreasing emissions are saving energy, utilising it efficiently and producing it through renewable and emission-free methods.

Everyone can affect their own greenhouse gas emissions through their consumption habits. Traffic emissions can be decreased by favouring public transport and by biking or walking to work or to the store.

Your food choices can also impact emissions. You could, for example, cut down on your consumption of beef and ensure that you do not throw away edible food. Individually, the most significant climate-friendly acts are cutting down on air travel and decreasing the energy consumption of housing.

​Mitigating climate change requires everyone’s investment.