Trees, Water and Climate

For many years we’ve been hearing about how rising CO2 levels are causing our climate to change. We’ve always wondered why other factors influencing our climate are hardly being discussed. When we stumbled on a scientific research paper looking at these other factors we were happy to finally be able to understand what’s really happening.

Our climate is a complex phenomena which is influenced by many factors. The sun sends energy to earth, which responds to it in multiple ways. For example, if sea water warms, evaporation increases, which leads to cloud formation, which in turn reflects part of the sun’s energy back to space, which then reduces further warming. During the night clouds are a kind of blanket, limiting the loss of heat to the universe.

On land evaporation works different, because obviously there is less water available. But who on a hot summer’s day takes a walk through a forest cannot fail to notice the much cooler temperatures under the trees. Trees are a sort of water pump and air conditioner in one, bringing up water from the soil to their leaves. Those leaves, through millions of openings evaporate that water, which then enters the atmosphere. A lot of trees together will evaporate a lot of water on a hot day, which condenses into clouds higher in the atmosphere. At high altitudes the water vapor cools again, so that when it falls down as rain it further cools the land. Maybe we can start to see the natural cycles that regulate our climate?

Let’s make another little connection in our head, because another thing trees do is taking CO2 from the air to take out the carbon (C), so they can grow, releasing the oxygen (O2) back into the air. What we need to remind ourselves of is that more CO2 in the air also means less O2 and that’s a balance we should probably not disrupt too much.

How all of this is connected to climate change becomes obvious when we realize how much forests we have cut down, and continue to cut down. We have a rising amount of cities and fields. This is now starting to affect nature’s regulation of our climate. Added to that we also handle rain water differently than forests do. Due to the thick layer of organic material on the forest floor a lot of rainwater stays in place and infiltrates the ground. A forest builds a water storage from which it takes to control the temperature by evaporation when needed. In our cities and on our fields we miss this water capturing ability, which leads to excessive runoff and loss of rainwater. Due to this process our landscapes are slowly drying out and temperature on land further increase over time as a result. Less forests means less cooling and deforestation so results in a sword that cuts both ways.

Another effect we experience is growing extremes in the weather. We see more and longer periods of drought and an increase in the amount of big storms. There are two reasons for this. First is that higher temperatures increase the amount of energy in the atmosphere. Big storms form by vertical flows in the atmosphere and these movements increase over hotter surfaces. These big storms are part of what we call the large water cycle, which generally bring rain from the oceans to the land. The small water cycle exists as well and brings us back to trees. Evaporation on land, by plants and trees feed the small water cycle. This small water cycle tends to produce smaller showers, the normal and more frequent rains so to speak.

Because trees moderate the temperature of the earth’s surface and increase cloud formation over land, the small water cycle influences the large water cycle, because it takes away part of the energy that drives the large water cycle. Here we understand the second reason for a more extreme climate through the loss of forests.

When we think about our climate we can only be effective if we put the natural processes and regulation of our weather at the center of our reasoning. Because we actively work against these processes we further and further disable nature’s way to balance our climate. At the same time the solutions are embarrassingly simple. We only need to do two things: infiltrate rain water into the ground wherever possible and plant trees, lots of them, wherever there is space. Like that we can allow nature to function and regulate our climate.

In closing another obvious observation: when we drain our landscapes as fast as possible as we do now, we increase the runoff from the land to the sea. If we keep doing that decade after decade, don’t you think sea levels are slowly going to rise? All that water does not just disappear, it has to go somewhere.

Let’s plant trees and forests to bring back the natural self-regulating state of our landscapes. The more trees we plant the more beautiful earth will look!