By Louis Silcox as seen in the Wilmot-Tavistock Gazette
This summer has been hot, and climate change scientists predict much hotter summers ahead. What can you do? Plant trees. Lots of trees.
How do trees keep us cool? First, they provide shade, protecting us from direct sunlight. But there’s more to it than that. Tree leaves don’t get hot the way roofs, sidewalks, roads, or parking lots do. Unshaded pavement can reach temperatures 11°C to 25°C hotter than the surrounding air. Even after the sun sets, these surfaces continue to release their stored heat, keeping the surrounding air warmer well into the evening.
So where does the sun’s energy go when it hits a tree?
Instead of heating up, trees (and other green plants) use much of that energy to power photosynthesis. That’s how they produce the food they need to grow and store energy for the future (we get that energy back when we burn wood).
Trees also cool the air through a process called transpiration. As they release water vapour from their leaves – hundreds of litres on a hot day – they create a natural cooling effect, much like sweat cools our bodies. A single large tree can release up to 380 litres of water each day.
The result? Streets lined with mature trees are several degrees cooler than those without them. A shaded sidewalk can feel up to 8°C cooler than one in full sun.
Every tree planted today helps create a cooler, healthier community tomorrow. Trees don’t just survive the heat – they help us beat it!
