Earth as a System: Energy, Matter and Life - Human Impact on Earth’s Processes

The Earth acts as a closed system for matter but an open system for energy, where solar radiation enters and heat radiation leaves. Human activities significantly alter this balance.

Greenhouse Effect: Human-induced emissions of gases like Carbon Dioxide ($CO_2$), Methane ($CH_4$), and Nitrous Oxide ($N_2O$) trap outbound long-wave infrared radiation, leading to Global Warming.

Ozone Layer Depletion: The release of Chlorofluorocarbons (CFCs) into the stratosphere leads to the breakdown of Ozone ($O_3$) molecules, increasing the amount of harmful Ultraviolet (UV) radiation reaching the surface.

Deforestation: Large-scale removal of trees disrupts the carbon cycle by reducing $CO_2$ sequestration and impacts the water cycle through reduced transpiration, leading to soil erosion and desertification.

Eutrophication: The runoff of chemical fertilizers containing Nitrogen ($N$) and Phosphorus ($P$) into water bodies causes excessive algal growth, which depletes dissolved oxygen and harms aquatic life.

Acid Rain: The combustion of fossil fuels releases oxides of Nitrogen ($NO_x$) and Sulfur ($SO_2$), which react with water vapor to form $HNO_3$ and $H_2SO_4$, lowering the $pH$ of precipitation.