10 questions and answers about forest, trees and climate

During the year there will be many discussions on many different levels regarding climate and climate change – and many questions will arise. Here we have summed up 10 common questions regarding forests, trees and climate – and tried giving relatively short answers. These short answers cannot cover every aspect of the problem and give a complete explanation, so we encourage you to also seek more knowledge on your own.

By Malene Bendix, Forest in Schools, Denmark
(Translated from Danish to English by Snorre Synnestvedt, Forest Society of Oslo and Akershus)

1. What is the greenhouse effect – and why does an increased greenhouse effect lead to climate change? [pic] Illustrated by Lise Sandberg

There is no longer any doubt: The world's climate is changing. Human activity during the last 100 years, with deforestation and the burning of oil and natural gas, has caused the amount of CO2 in the atmosphere to increase to a level the Earth is not “used to”. The atmosphere surrounds our planet as a layer of gas – a layer that kind of works in the same way as the glass in a greenhouse. Sunlight passes through this layer and is absorbed as heat by the Earth. Some of this heat his radiated back into space, but the extra CO2 in the atmosphere is now trapping too much of this heat.

That is why the Earth's temperature is rising – and why our climate is changing. During the last 100 years the global surface temperature has risen by 0,7 °C. The next 100 years scientists think it likely that the temperature will rise a further 1,5 to 6 °C.

This can cause many changes. Already we can see that polar ice is melting. Sea levels are expected to raise flooding low-lying land and islands and changing the coastline. More extreme weather, with more storms, more rainfall and more drought with increased desertification in areas around the Equator. All this can and will have a great impact on humans and all life on Earth. People will have to leave there homes. Species will become extinct.

Prospects are overwhelming, but we are not helpless. If we act now, it can make a big difference to the extent of the problems we will be facing the next 100 years.
Planting trees is one way to counter climate change. Saving energy is another. And the invention of new solutions is a third way. They are all important.

2. What is the carbon cycle – and how does it influence the climate?

Carbon is found many different places in our environment – dissolved in oceans and lakes, in the biomass of plants and animals, in the atmosphere as CO2, in rocks and soils, and underground as oil, coal, etc..

Carbon is constantly exchanged between the different carbon sources and carbon stocks in a process known as the carbon cycle. Carbon is primarily exchanged in the form of CO2 – and the carbon stocks are actually stocks that can absorb CO2 and reduce its concentration in the atmosphere.

Humans and the carbon cycle
Each year humans emit 7 900 million tons of carbon into the atmosphere through the burning of fossil fuels and deforestation. Carbon stocks such as lakes, oceans and afforested land trap 4 600 million tonnes. This means that we are increasing the amount of carbon in the atmosphere by 3 300 million tons per year. It is not sustainable.

To deal with this we must at once emit less CO2, stock carbon in new and existing forests and wood products, and develop alternative energy sources to coal, oil and gas.

Some figures
The European forests (outside Russia) hold 9 552 million tons of carbon. This amount is increased each year with 115,83 million tons of carbon. The Russian forests stock 37 000 million tonnes of carbon and has an annual increases of 440 million tons of carbon.

3. Why is planting trees helping to reduce climate change?

There are two ways of reducing the amount of CO2 in the atmosphere. We can emit less CO2 – and we can remove CO2