Understanding Environmental Impacts, Climate Change, and Natural Hazards
Environmental Impacts and Natural Hazards
Environmental Impact: Changes caused by living things.
Environmental Risk: Irreparable damage to the environment.
Natural Processes: Events such as volcanoes, droughts, and earthquakes.
Anthropogenic Processes: Pollution and arson caused by human activity.
Climate Change
Climate change refers to global shifts in Earth’s climate, including variations in temperature, precipitation, and wind patterns, as well as the frequency and intensity of extreme weather events like hurricanes and droughts. These changes are primarily driven by human activities.
The Greenhouse Effect
The greenhouse effect is the process where increased levels of CO2, water vapor, and methane in the atmosphere trap infrared rays. This prevents heat from escaping into space, leading to an increase in the average temperature of the Earth. This process is currently intensifying.
Causes of Climate Change
Increased emissions of greenhouse gases, especially CO2, trap heat and cause a temperature increase. CO2 emissions result from both natural phenomena (respiration of living beings, decomposition of organic matter, and volcanic eruptions) and artificial phenomena (combustion of fossil fuels and deforestation).
Effects of Climate Change
- Temperature increase of the atmosphere.
- Melting of glaciers and polar ice caps.
- Increased sea level.
- Increased evaporation leading to more intense rainfall and floods.
- Increasing soil temperature leading to desertification.
- Expansion of tropical diseases.
Solutions to Climate Change
- Reducing CO2 emissions into the atmosphere.
- Implementing energy-efficient measures and increasing the use of non-fossil fuels.
- Avoiding deforestation.
Air Pollution
Air pollution is caused by an increase in certain toxic gases in the air (CO2, NOx, SO2). While developed countries are major contributors, pollution is a global problem. The atmosphere can cleanse itself to some extent, but when pollution levels are very high, reducing emissions is the only solution.
Weakening of the Ozone Layer
The ozone layer is a region of the atmosphere formed by ozone (O3) that absorbs ultraviolet radiation (UVA). UVA radiation can cause mutations in living organisms. It was discovered 15-20 years ago that the ozone layer over the poles was thinning due to ozone-depleting gases like chlorofluorocarbons (CFCs). These gases react and produce chlorine, which destroys ozone.
Consequences of Ozone Layer Depletion
- Increased DNA mutations and skin cancer rates.
- Reduced crop yields.
- Alteration of soil microorganisms.
- Elimination of plankton.
- Weakening of the immune system.
- Increase in eye injuries.
Acid Rain
Acid rain has a high pH. It is primarily caused by the burning of fossil fuels, which releases sulfur and nitrogen oxides into the atmosphere. These oxides combine with water vapor to form sulfuric and nitric acid, which then fall as acid rain in specific areas.
Effects of Acid Rain
- Acidifies lagoons and ponds, impacting ecosystems.
- Alters soil composition and nutrient distribution, increasing the amount of heavy metals.
- Destroys forests.
- Causes respiratory problems and conjunctivitis.
- Destroys monuments (stone disease).
Seismic Hazards
Seismic hazards occur within the boundaries of tectonic plates. Earthquakes produce three types of waves: surface waves (which cause the most devastation), primary waves, and secondary waves.
Volcanoes
Volcanoes are fissures in the lithosphere where materials from the Earth’s interior are released. These materials include:
- Solid: Piroclasts (blocks, bombs, lapilli, and ash).
- Liquid: Magma that forms molten lava flows.
- Gases: S, N, and H2O.
Effects of a Volcano
- Lava flows.
- Pyroclastic material rain, ash.
- Ash clouds.
- Lahars.
- Noxious fumes.