Climate feedback loops are processes that either amplify or stabilize changes in the Earth’s climate system. These loops are critical in understanding how global temperatures respond to disturbances, especially in relation to global warming and energy balance.
In IB Geography, feedback loops are key to explaining why climate change does not always follow a linear path.
There are two main types of feedback loops: positive feedback loops, which reinforce the initial change, and negative feedback loops, which counteract, dampens and slows down warming. Both play a vital role in shaping long-term climate trends and are closely linked to concepts like albedo, insolation, and the global atmospheric energy budget.
Melting Arctic Ice as a Positive Climate Feedback Loop
A well-known example of a positive feedback loop is the melting of Arctic sea ice. As global temperatures rise, more ice melts, exposing darker ocean surfaces. Unlike ice, which has a high albedo and reflects most incoming shortwave solar radiation, the ocean absorbs much of this energy. The increase in absorbed heat accelerates local warming, which in turn causes more ice to melt. This creates a self-reinforcing cycle that amplifies warming in polar regions. This process is known as polar amplification, and it’s a strong contributor to regional and global climate shifts.
Increased Cloud Cover as a Negative Climate Feedback Loop
In contrast, increased cloud cover can form part of a negative feedback loop in the climate system. When temperatures rise, more surface water evaporates, increasing atmospheric moisture. This leads to more cloud formation, especially in the lower atmosphere. Clouds reflect a significant portion of incoming insolation—shortwave solar radiation—back into space. As a result, Earth’s surface albedo increases, reducing the amount of heat absorbed. This helps cool the planet, thereby moderating the rate of global warming. However, the effect of clouds varies depending on their type, altitude, and thickness, which adds complexity to climate predictions.
Greenhouse Gases
A factor that we must quote about the accelerating global warming, is greenhouse gases (GHGs), atmospheric gases that trap heat within the Earth’s atmosphere. While they play a crucial role in maintaining Earth’s temperature through the natural greenhouse effect, increased concentrations from human activities—known as enhanced greenhouse gases (eGHGs) drive global warming which then triggers positive feedback loops.
Why Feedback Loops Matter in IB Geography
Feedback loops frequently appear in IB Geography exam questions, particularly in topics related to atmospheric systems, energy budgets, and climate change. Understanding the difference between positive and negative feedback—and knowing examples like Arctic ice melt and cloud cover—is essential for strong exam responses. They also offer insight into how human and natural processes influence the global energy balance and long-term climate patterns.
Read here for more on Atmospheric Energy Budget
Read here for more on Impacts of Global Warming
Full Global Climate Change Notes available