07:43
Faizan
Deforestation occurs when trees in a forest are destroyed faster than they can replace themselves. Natural deforestation happens during extreme weather events such as hurricanes and ice ages. Fire from lightning or volcanic eruptions destroys trees. Man-made deforestation is the clearance of trees so the land may be used for agricultural crops, ranches and urban development. Forests affect cloud formation, rainfall and temperature. They regulate weather through their absorption of solar energy, creation of rainfall and exchange of atmospheric gases. Deforestation causes soil erosion and flooding.
Albedo
Albedo is the measure of the power with which any surface reflects sunlight. Forests absorb solar radiation through leaves on trees and have a low albedo. Deforested regions have a high albedo and reflect more solar energy. As the albedo increases with deforestation, the reduction of absorbed energy also reduces air convection currents and rainfall. The daily variation of temperatures increases with forest clearance.
Evapotranspiration
Forests absorb water and nutrients from the soil through their root systems and evaporate it back into the atmosphere from their leaves. This is the process of evapotranspiration where the tree acts as a humidifier for the air. Most of the moisture in inland regions such as Central Africa comes from forests. Coastal regions receive moisture from water vapor evaporation from the surface of the oceans. Deforestation slows down precipitation and leads to drought. As tree roots no longer tap ground water, the groundwater levels fall. Tree roots also hold the soil together. Their removal loosens the soil, causing erosion and flooding.
Aerodynamics
The topmost leaves in a forest, the canopy, create a rough surface. The roughness provides friction with air currents and increases air turbulence. The turbulence provides momentum to global air circulation patterns. Tropical rain forests pump heat into the atmosphere during evapotranspiration. This air in turn circulates to cooler temperate regions on the globe. Forests also allow some air through the trees as well as over and around them. This way they slow down winds. Deforestation contributes to an increase of local wind speeds and a cooling of temperate regions.
Pollution
Forest-clearing fires release aerosols -- particulate matter such as soot -- into the atmosphere. Aerosols both heat and cool the air. Light-colored particles reflect incoming solar radiation back into space and contribute to falling temperatures. Dark-colored particles absorb solar radiation and increase temperatures. Clouds form around soot aerosols but the cloud droplets do grow large enough to trigger rainfall. The decomposition of organic matter after a fire increases carbon dioxide levels in the atmosphere.
Albedo
Albedo is the measure of the power with which any surface reflects sunlight. Forests absorb solar radiation through leaves on trees and have a low albedo. Deforested regions have a high albedo and reflect more solar energy. As the albedo increases with deforestation, the reduction of absorbed energy also reduces air convection currents and rainfall. The daily variation of temperatures increases with forest clearance.
Evapotranspiration
Forests absorb water and nutrients from the soil through their root systems and evaporate it back into the atmosphere from their leaves. This is the process of evapotranspiration where the tree acts as a humidifier for the air. Most of the moisture in inland regions such as Central Africa comes from forests. Coastal regions receive moisture from water vapor evaporation from the surface of the oceans. Deforestation slows down precipitation and leads to drought. As tree roots no longer tap ground water, the groundwater levels fall. Tree roots also hold the soil together. Their removal loosens the soil, causing erosion and flooding.
Aerodynamics
The topmost leaves in a forest, the canopy, create a rough surface. The roughness provides friction with air currents and increases air turbulence. The turbulence provides momentum to global air circulation patterns. Tropical rain forests pump heat into the atmosphere during evapotranspiration. This air in turn circulates to cooler temperate regions on the globe. Forests also allow some air through the trees as well as over and around them. This way they slow down winds. Deforestation contributes to an increase of local wind speeds and a cooling of temperate regions.
Pollution
Forest-clearing fires release aerosols -- particulate matter such as soot -- into the atmosphere. Aerosols both heat and cool the air. Light-colored particles reflect incoming solar radiation back into space and contribute to falling temperatures. Dark-colored particles absorb solar radiation and increase temperatures. Clouds form around soot aerosols but the cloud droplets do grow large enough to trigger rainfall. The decomposition of organic matter after a fire increases carbon dioxide levels in the atmosphere.
Posted in: Go Green
