Climate change is a long-term shift in Earth's climate, typically over decades, leading to weather changes.
Global warming is the increase in Earth's average surface temperature due to greenhouse gases.
Temperatures have risen globally by approximately 0.8°C over the last 100 years, with Europe warming faster (by 1.3°C in the twentieth century).
Rising global temperatures can be dangerous to the balance of nature.
Surface Reflectivity
Lighter-colored objects (e.g., snow, ice, clouds) reflect more heat energy back into space, helping Earth remain cool.
Darker-colored objects (e.g., oceans, forests, soil) absorb more heat from the Sun, warming up Earth.
Earth usually absorbs around 70% of sunlight and reflects 30%; melting ice and snow due to global warming can disrupt this balance.
Global Dimming
Burning fossil fuels releases particles (soot, ash) into the air, which allows water vapor to gather and create larger clouds.
Polluted clouds contain more water and act like mirrors, reflecting more sunlight back into space (global dimming).
Global dimming can lead to colder water temperatures and decreased rainfall, potentially causing drought.
Oceans and Climate
Oceans trap heat energy from the Sun and distribute it around Earth via currents, maintaining heat transfer.
Oceans absorb approximately 40% of the carbon dioxide released into the atmosphere.
CO₂ is an acidic gas; when dissolved in water, it makes the water more acidic, affecting marine life.
Oceans are also absorbing 90% of the excess heat generated by increased greenhouse gases.
Warmer water absorbs less CO₂, which can cause more heat to stay in the atmosphere and further warm the planet.
There are sections of the North Atlantic that are currently unable to absorb as much CO₂ as they used to.
Carbon Dioxide
There has been a 40% increase in the level of carbon dioxide concentration in the atmosphere since the Industrial Revolution in the late 1700s, according to NASA scientists.
Excess carbon dioxide is causing the worldwide climate to change.
Factors of Climate Change
Oceans: Absorb heat/CO2, distribute heat via currents.
Surface Reflectivity: Reflection of sunlight by surfaces.
Global Dimming: Reflection of sunlight by polluted clouds.
Greenhouse Effect
The greenhouse effect occurs when gases in Earth's atmosphere prevent some of the heat from escaping into space.
Greenhouse gases trap heat in the atmosphere, making Earth warmer.
Main greenhouse gases: Carbon dioxide CO<em>2, methane CH</em>4, nitrous oxide N<em>2O, and water vapor H</em>2O.
Increased burning of fossil fuels has disrupted the balance of carbon dioxide, resulting in global warming and climate changes.