Global warming

Definition

Global warming refers to the long-term increase in Earth's average surface temperature due to human activities, primarily the release of greenhouse gases like carbon dioxide and methane into the atmosphere. This phenomenon is intricately linked to various atmospheric processes, including terrestrial radiation and the greenhouse effect, influencing the chemical composition of the atmosphere and the overall climate system. As temperatures rise, it impacts climate models' predictions and causes significant changes in weather patterns and ecosystems.

5 Must Know Facts For Your Next Test

1. The Earth's average temperature has increased by about 1.2 degrees Celsius since the late 19th century, largely driven by human activities.
2. The greenhouse effect is a natural process that warms the Earth, but human-induced global warming intensifies this effect through increased emissions of greenhouse gases.
3. Ocean absorption of excess heat is causing sea levels to rise and affecting marine ecosystems, which in turn impacts global weather patterns.
4. Climate models project that if current trends continue, global temperatures could rise by an additional 1.5 to 4 degrees Celsius by the end of the century.
5. Impacts of global warming include more frequent and severe weather events, loss of biodiversity, and changes in agricultural productivity across different regions.

Review Questions

• How does terrestrial radiation contribute to the phenomenon of global warming?
  • Terrestrial radiation refers to the infrared energy emitted by Earth as it absorbs sunlight. As global temperatures rise due to global warming, the amount of terrestrial radiation increases. However, elevated levels of greenhouse gases trap more of this outgoing energy in the atmosphere instead of allowing it to escape into space. This enhanced greenhouse effect leads to further warming, creating a feedback loop that exacerbates climate change.
• Evaluate how changes in the chemical composition of the atmosphere relate to global warming and its potential impacts on climate models.
  • The chemical composition of the atmosphere has changed significantly due to human activities, particularly through increased concentrations of greenhouse gases like carbon dioxide and methane. These changes directly affect global warming by enhancing the greenhouse effect. As climate models incorporate these alterations in atmospheric composition, they become crucial tools for predicting future climate scenarios. Accurate modeling is essential for understanding potential impacts on weather patterns, sea-level rise, and ecological responses.
• Synthesize information on how global warming affects multiple components of the climate system and evaluate its implications for future climate change impacts.
  • Global warming impacts several components of the climate system, including the atmosphere, oceans, land surfaces, and cryosphere. For example, rising temperatures lead to increased evaporation rates, altered precipitation patterns, and shifting ocean currents. These changes can create extreme weather events and disrupt natural ecosystems. As we synthesize this information, it becomes clear that continued global warming will likely exacerbate existing issues like food security and health risks while also challenging adaptive capacities across various regions globally.

Related terms

Greenhouse gases: Gases in the atmosphere that trap heat, contributing to the greenhouse effect; major examples include carbon dioxide, methane, and nitrous oxide.

Climate feedbacks: Processes that can either amplify or diminish the effects of climate change; for example, melting ice reduces reflectivity, leading to further warming.

Anthropogenic emissions: Greenhouse gas emissions that result from human activities, such as burning fossil fuels, deforestation, and industrial processes.