New Animation: Carbon capture in timber

 

Everyone is aware that the climate is in trouble. With increasing pressure to help tackle the climate emergency in the construction industry, experts are promoting the environmental benefits of carbon sequestration in timber and what we can do to help them slow down the rate of global warming whilst providing a sustainable resource for construction.

The air is a mixture of gases, mostly oxygen, nitrogen and carbon dioxide. They are all equally important in managing the natural environment. Co2 has gained negative connotations as it’s the main gas that is contributing to climate change, however, it’s still a crucial part of the atmosphere as without it plant life would die, and temperatures would drop by an average of 6 degrees worldwide.

The problem is that there's simply too much of it. Modern life and excessive fossil fuel use means there is a lot more carbon dioxide, and nature cannot keep up, resulting in the ecological disaster we see playing out today.

It’s widely understood that cutting down natural forests is the worst thing you could do to decrease greenhouse gases in the atmosphere. However, society is less aware of the role sustainable forestry can play in saving the earth.

Sustainable forestry

Deforestation is the removal of a forest from natural habitats such as rainforests that is then converted to non-forest use, so trees are cut down and the land they came from is used for building, farming and so on. Trees capture a lot of carbon, so when removed in mass, the global carbon stores decrease and less CO₂ is converted to oxygen.

However, there is a sustainable option that means we can still use wood as a resource without negatively impacting the environment. Modern production forests are designed to provide us with enough timber, whilst also being strategically managed to make sure not too many trees are harvested, and new ones are planted in their place. They include open ground, native tree species, productive broadleaves and a mixture of conifer species to ensure biodiversity whilst maximizing the carbon efficiency of the cycle. When wood is produced in this way, it actively plays a positive role in removing CO₂ from the atmosphere through a process known as carbon sequestration.

How does carbon sequestration work?

The leaf

It all begins with a leaf. The leaves take in carbon dioxide particles through tiny holes on their surface and combine them with water particles. Using energy from sunlight, they create oxygen and carbohydrates which act as food for the plant. The CO₂ absorbed by the leaves gets locked in the tree’s wood, no longer contributing to the climate crisis. The more wood, the less harm to the atmosphere.

The tree

Once the carbon is stored in the wood, the tree helps ecosystems to thrive, giving us life sustaining oxygen. Once trees are harvested for timber materials, the carbon in the wood continues to be stored during the product's whole life. Trees are harvested after 40 years, with each tree potentially producing 1.14m³ of timber, and storing 743kg of carbon. After those 40 years the timber product it is made into could last a very long time, storing that carbon within it for years.

The forest

Modern forests include areas of open ground, native trees, productive broad leaves and a mix of conifer species. The forests are managed in smaller areas called coupes. These coupes are felled at different intervals to create varied structure within the forest and to enhance biodiversity. After 20 years the weaker trees are harvested for wood products such as panel boards allowing the remaining trees to access more sunlight to photosynthesize and continue to grow to full height and volume. After another 20 years, most of the remaining trees in the coupe are felled mostly to manufacture long-life products and new saplings are planted. However, the native species are left standing to retain that biodiversity.

Sustainable, commercial forests are always replaced after harvest, so a continuous cycle of carbon capture is maintained.

Timber products

Timber products hold the carbon that their original tree captured. Everything you come across in daily life that is made of wood contains carbon and if disposed of carefully at the end of its life, can be recycled and reused to increase the storage period even more.

Construction and design are huge industries that could make a significant impact on our global carbon stores. Using timber not only continues the life of existing stores but will increase the demand for sustainable production forests, meaning more trees to help manage the harmful amounts of atmospheric CO₂ caused by human activity

You can find out more about the environmental benefits of wood here.