Climate sensitivity

Definition

Climate sensitivity refers to the measure of how much the Earth's average temperature will increase in response to a doubling of carbon dioxide (CO2) concentrations in the atmosphere. This concept is crucial for understanding future climate projections, as it helps scientists estimate the potential impacts of greenhouse gas emissions on global temperatures and climate systems over time.

5 Must Know Facts For Your Next Test

1. Climate sensitivity is usually estimated to be between 1.5°C and 4.5°C, indicating a range of possible temperature increases with doubled CO2 levels.
2. Higher climate sensitivity values suggest a greater risk of severe climate impacts, including more extreme weather events and changes in precipitation patterns.
3. Climate models play a critical role in determining climate sensitivity by simulating different scenarios of greenhouse gas emissions and their effects on global temperatures.
4. Understanding climate sensitivity is essential for policymakers, as it informs strategies for mitigation and adaptation in response to climate change.
5. Uncertainties in climate sensitivity arise from variations in feedback mechanisms, natural climate variability, and differences among various climate models.

Review Questions

• How does climate sensitivity impact predictions made by climate models regarding future temperature increases?
  • Climate sensitivity directly influences predictions made by climate models because it provides a framework for estimating how much warming will occur in response to increased greenhouse gas concentrations. By understanding the range of possible climate sensitivities, scientists can better gauge the extent of future temperature rises under various emission scenarios. This helps refine projections and identify potential climate impacts that society may face if emissions continue to rise.
• What role do feedback mechanisms play in determining the overall climate sensitivity, and how might they complicate future projections?
  • Feedback mechanisms are critical to understanding overall climate sensitivity because they can either amplify or dampen temperature responses to increased greenhouse gases. For example, positive feedbacks like melting ice leading to lower albedo can enhance warming, while negative feedbacks may have a cooling effect. These interactions complicate future projections because they introduce uncertainties into models; predicting how these feedbacks will behave in a changing climate remains a significant challenge for scientists.
• Evaluate the implications of different estimates of climate sensitivity on global policy decisions regarding climate change mitigation.
  • Different estimates of climate sensitivity can significantly shape global policy decisions concerning climate change mitigation strategies. A higher estimate would indicate a more urgent need for aggressive emission reduction policies to avoid severe impacts from rising temperatures. Conversely, lower estimates might lead to more complacent approaches. Understanding the range of uncertainty in climate sensitivity is essential for policymakers to weigh the risks and benefits of various strategies and to prioritize actions that align with projected outcomes based on robust scientific evidence.

Related terms

radiative forcing:

Radiative forcing is the change in energy balance in the Earth's atmosphere due to factors like greenhouse gas emissions, which affects climate sensitivity and temperature changes.

feedback mechanisms: Feedback mechanisms are processes that can either amplify or dampen the effects of climate sensitivity, such as ice-albedo feedback or water vapor feedback, influencing future climate projections.

equilibrium climate sensitivity (ECS): Equilibrium climate sensitivity (ECS) specifically refers to the long-term temperature increase expected after the climate system has fully adjusted to a doubling of CO2 concentrations.