How Plants Can Change Our Climate?

Plant growth can have a considerable effect on the climate,” says Wolfgang Buermann, a geographer at Boston University. He explains that there are several ways in which plants can alter the temperature of the Earth’s atmosphere. Through the process of photosynthesis, plants use energy from the sun to draw down carbon dioxide from the atmosphere and then use it to create the carbohydrates they need to grow. Since carbon dioxide is one of the most abundant greenhouse gases, the removal of the gas from the atmosphere may temper the warming of our planet as a whole.

Plants also cool the landscape directly through the process known as transpiration. When the surrounding atmosphere heats up, plants will often release excess water into the air from their leaves. By releasing evaporated water, plants cool themselves and the surrounding environment. “It’s like sweating. When you sweat you cool the surface of your skin,” says Buermann. Over a forest canopy or a vast expanse of grassland, large amounts of transpiration can markedly increase water vapor in the atmosphere, causing more precipitation and cloud cover in an area. The additional cloud cover often reinforces the cooling by blocking sunlight.

As plants ‘breathe’ and ‘perspire’ they help cool the atmosphere. Plants consume carbon dioxide—a significant greenhouse gas—in the process of photosynthesis. The reduction of carbon dioxide in the atmosphere has an indirect cooling effect. Plants also cool the atmosphere because they release water vapor when they get hot, a process similar to sweating. The diagram at left shows the microscopic structure of a leaf, and the processes of photosynthesis and transpiration.