Increasing Risk Of Storms, Droughts and Floods
Trees are vital for the health and balance of our planet. They provide oxygen, store carbon, support biodiversity, regulate water cycle and protect soil. However, humans are cutting down trees at an alarming rate, causing deforestation and degradation of forests around the world. This has serious consequences for the climate and the frequency and intensity of extreme weather events.
Some of the effects of deforestation on climate are:
- Greenhouse gas emissions: Trees absorb carbon dioxide from the atmosphere and store it in their biomass. When trees are cut down or burned, they release carbon dioxide back into the air, contributing to global warming. Deforestation is responsible for about 10% of global greenhouse gas emissions.
- Albedo change: Trees have a low albedo, meaning they reflect less sunlight than bare land. When trees are removed, more sunlight is reflected back to space, cooling the local temperature. However, this also reduces the amount of heat trapped by greenhouse gases in the lower atmosphere, weakening the convection currents that drive rainfall patterns. This can lead to droughts in some regions and floods in others.
- Evapotranspiration change: Trees release water vapor into the air through evapotranspiration, creating clouds and precipitation. When trees are lost, less water vapor is available for cloud formation, reducing rainfall and increasing dryness. This can also affect the movement of moisture across continents, affecting the climate of distant regions.
- Soil erosion: Trees protect the soil from erosion by wind and water. When trees are cleared, the soil becomes exposed and vulnerable to erosion, losing its fertility and organic matter. This can reduce the ability of the soil to store water and carbon, exacerbating droughts and emissions.
The changes in climate caused by deforestation can increase the risk of storms, droughts and floods in different ways:
- Storms: Deforestation can alter the atmospheric circulation and pressure gradients, affecting the formation and intensity of storms. For example, deforestation in Southeast Asia has been linked to increased frequency and severity of El Niño events, which can trigger storms and floods in some regions and droughts in others.
- Droughts: Deforestation can reduce rainfall and soil moisture, creating dry conditions that can lead to droughts. For example, deforestation in the Amazon rainforest has been associated with reduced rainfall and increased risk of droughts in South America.
- Floods: Deforestation can increase runoff and reduce infiltration, causing more water to flow over the land surface rather than into the ground. This can increase the risk of floods and landslides, especially during heavy rains. For example, deforestation in Haiti has been blamed for worsening the impacts of hurricanes and floods.
Deforestation is a major threat to the climate and the well-being of people and nature. To prevent further damage and restore what has been lost, we need to stop cutting trees and start planting them. By conserving and restoring forests, we can reduce greenhouse gas emissions, enhance rainfall, protect soil and biodiversity, and mitigate the risk of storms, droughts and floods.