Introduction to Glaciation and the Glacial Budget

🏔️ Glacial systems are natural systems that form ice sheets and glaciers and have effects on the landscape.

🔃 Inputs to a glacial system include snowfall and avalanches, while outputs include melt water and moraine.

⚖️ The balance between inputs and outputs is known as the glacial budget, which determines the mass gained or lost by the glacier.

🏔️ The mass lost and gained by a glacier determines its budget, with positive budgets indicating growth and negative budgets indicating shrinkage.

🌡️ The snow line of a glacier is influenced by factors such as slope aspect and position, with more insulation leading to higher snow lines and increased melting.

🗺️ Glacial budgets can vary on different sides of a slope, with the southern side having a higher chance of snow advance and the northern side having a lower snow line and more permanent snow cover.

❄️ The initial snowfall has a open structure with lots of air pockets, known as nevaeh or fresh snow.

🧊 As the fresh snow accumulates, it becomes more compact and the air is expelled, turning the color from white to pale blue.

🏔️ If the accumulated snow becomes large enough, it will transform into a glacier over a period of 20 to 40 years.

🏔️ Glaciers have two zones: accumulation and ablation. In the accumulation zone, inputs are greater than outputs, resulting in mass gain.

❄️ The equilibrium line is the boundary between the zones of ablation and accumulation, where net loss is equal to net gain.

📈📉 The glacial budget is determined by the difference between accumulation and ablation. A positive net balance indicates glacier advance, while a negative net balance indicates glacier retreat.

Glaciers advance and retreat based on the balance of inputs and outputs.

Glaciers can be warm-based or cold-based depending on their location.

Warm-based glaciers are smaller valley glaciers, while cold-based glaciers are larger ice caps and ice sheets.

❄️ The differences between warm-based and cold-based glaciers are due to the climate they are located in, resulting in different glacial budgets.

🌊 Warm-based glaciers have high melt rates due to high winter snowfall and summer temperature, leading to fast movement and a thin layer of fresh snow on the surface.

🗻 Cold-based glaciers have low precipitation and melt rates, resulting in slow movement and a build-up of ancient ice over thousands of years.

🧊 Glaciation involves the separation of icebergs under pressure from the main body of the glacier.

📊 The glacial budget is the balance between the inputs and outputs to the glacier, determining its growth or retreat.

⏳ The glacial budget can be analyzed in terms of zones of the glacier or time scales, such as seasons or years.