How Trees Can Help Fight Global Warming

For this week’s blog we discuss how trees can help fight global warming.

Now more than ever, global warming is in the news. Even chilly, rainy Britain has been experiencing the consequences of the warming trend, from unusually hot summers to stormy, flood-prone winters.

Whatever else you’re doing to combat global warming, there’s one especially positive step you can take: plant trees and take excellent care of them. We explain why.

Trees ‘Lock Up’ Greenhouse Gases While Growing

You’ve probably heard that trees are a very good thing because they produce oxygen for us to breathe. While this is true, it’s only part of a much bigger picture.

Trees also remove carbon dioxide from the atmosphere and turn it into cellulose, an important component of the tree’s structure (think of cellulose as something very roughly akin to your skeleton).

This is a significant observation because carbon dioxide (often shortened to its chemical formula, CO₂) is a major cause of global warming.

When there’s too much of it in the atmosphere, as at present, it absorbs a lot of the heat reflected by the earth. This heat would otherwise be radiated into space.

In this way, carbon dioxide turns the earth’s atmosphere into a kind of greenhouse, which is why it is often referred to as a greenhouse gas.

Trees turn CO₂ into cellulose through a process called photosynthesis, the mechanics of which you almost certainly slept your way through in school.

It’s a complicated piece of biochemistry, but all you really need to remember is this: as trees grow, they capture more and more atmospheric carbon and incorporate it into their branches, leaves, roots and trunk.

Most trees are prolific carbon-grabbers, and will store more carbon than they release until they reach old age.

Trees Reflect Solar Radiation Back Into Space

Not only do trees actively remove carbon dioxide (a powerful greenhouse gas) from the environment, they also act as reflectors for the sun’s rays. This reflective mechanism—known as the albedo effect—helps keep the earth cool.

The phenomenon isn’t unique to trees, but it is something they do well, especially where there are large numbers of them planted together.

One interesting aspect of the albedo effect of trees is its variability. A recent research paper from France suggests that traditional broad-leaved tree species such as birch, oak and hazel are much better at reflecting solar radiation than conifers.

For us that’s just one more reason to choose native tree species over exotics (there are of course conifer species native to the British Isles, but only three of them: yew, juniper and scots pine).