Using Figure 8 and your own knowledge, assess the relative importance of factors leading to the development of this landscape - AQA - A-Level Geography - Question 4 - 2021 - Paper 1

To assess the factors leading to the development of the periglacial landscape shown in Figure 8, we must consider both the physical characteristics of the environment and the climatic conditions.

1. Thermokarst Formation

Thermokarst is a significant process in the formation of this landscape. In periglacial regions, the melting of ice-rich permafrost results in the development of irregular depressions and lakes. As the ice melts, water accumulates, forming the small, medium, and large lakes visible in the image. This process is influenced heavily by local relief, which dictates where the water collects.

2. Climate and Temperature Variation

The aerial photograph indicates that the region is experiencing a temperature increase which facilitates permafrost thawing during the summer months. The time of the image capture, early summer, suggests that much of the ice still remains, yet its rates of melting are rapid due to rising temperatures. Understanding thermal dynamics is crucial in comprehending how permafrost evolves into thermokarst landscapes.

3. Local Relief Characteristics

Local topography plays a vital role in the rate of ice melting. Areas with gentle slopes may allow for more efficient drainage of melted water, influencing the formation of larger lake systems. In contrast, more rugged areas may trap water, causing varied lake sizes across the landscape.

4. Geomorphological Processes

Interactions between ice, water, and the underlying geology are crucial for thermokarst formation. Mechanical weathering processes, as well as chemical weathering of the soil, contribute to the landscape’s evolution. Furthermore, periglacial features such as polygons indicate active processes that shape the terrain.

Conclusion

In conclusion, while thermokarst is the central factor, it is essential to view it in conjunction with climatic conditions, local relief, and geomorphological processes. These factors interact intricately to govern the landscape's development as observed in Figure 8.