Oil Extraction in Alaska Flashcards
How does the extraction and transportation of oil impact the periglacial landscape system?
The extraction and transportation of oil can impact the processes, flows of material, and energy through the periglacial landscape system.
How are material flows affected by oil extraction?
Material flows are affected by the use of gravel pads, where gravel is extracted from stream and river beds for road construction. The loss of gravel alters the rate of transportation and deposition downstream, affecting the equilibrium between erosional and depositional processes in the river system.
What impact does gravel extraction have on the periglacial landscape system?
Gravel extraction disrupts the natural flow of material, altering the transportation and deposition of gravel downstream, and influencing the balance between erosional and depositional processes in river systems.
How are hydrological processes affected by gravel extraction?
Gravel extraction from a glacial outwash aquifer near Palmer resulted in a drop of over a meter in groundwater levels within a 2 km radius of the extraction site.
How are energy flows affected by oil extraction and drilling processes?
Energy flows are affected by the release and burning of gases during drilling. Flaring releases carbon dioxide into the atmosphere, contributing to the greenhouse effect. Methane is also vented without burning, further contributing to the greenhouse effect. Additionally, heat produced by extraction, transportation processes, and associated infrastructure raises temperatures in the surrounding environment.
What gases are released during drilling, and what are their impacts?
During drilling, gases such as carbon dioxide and methane are released. Carbon dioxide contributes to the greenhouse effect, while methane is a potent greenhouse gas. Both gases trap terrestrial radiation in the lower atmosphere, raising temperatures.
What impact does oil extraction have on the urban heat island effect?
In the small town of Barrow, Alaska, oil production contributes to the urban heat island effect, with mean temperatures averaging 2.2°C higher than in the surrounding rural area. On calm days, temperature differences of up to 6°C have been measured. The heat released by oil-related activities, including domestic heating systems in poorly insulated buildings, contributes to the elevated temperatures in the area.
How does oil production affect temperature fluctuations and freeze-thaw cycles?
Since drilling began, there has been a reduction of 9 percent in the number of days with temperature fluctuations around 0°C (freeze-thaw cycles). The energy released to the environment by oil-related human activities disrupts the natural freeze-thaw processes.
What are the consequences of oil extraction for the periglacial landscape system?
Oil extraction disrupts material flows, alters hydrological processes, and affects energy flows within the periglacial landscape system. These impacts can have implications for river systems, groundwater levels, temperature patterns, and natural freeze-thaw cycles.
What is permafrost?
Permafrost is perennially frozen ground that remains frozen from one year to the next, despite rising above-zero temperatures in the summer.
What is the active layer in permafrost regions?
The active layer is a shallow surface layer of material that overlays the permafrost. It thaws in the summer but freezes again during the winter.
Why does the permafrost experience less temperature variation compared to the active layer?
The permafrost is not directly exposed to the seasonal differences in air temperature, which is why it experiences less temperature variation compared to the active layer.
How can buildings and infrastructure impact permafrost?
The heat released by buildings and infrastructure can lead to the thawing of permafrost and a longer period of melting for the active layer.
What happens if a building is constructed directly onto the ground surface in permafrost regions?
If a building is constructed directly onto the ground surface in permafrost regions, some of the heat produced by the heating systems may transfer through the floor to the ground, resulting in the melting of permafrost.
What are the consequences of permafrost thawing due to building heat?
Thawing permafrost can lead to subsidence and increase the mobility of the active layer. It can also result in solifluction, a type of mass movement.
