GEOG 102 Midterm 1 Review

Mid-Term Structure

• Examination consists of 10 multiple-choice questions and 7 short answer questions.
• Students must answer 5 short answer questions, each worth 4 marks.
• Responses should be written in full sentences; diagrams are encouraged for clarity.

Study Strategy

• Identify core concepts from each lecture.
• Utilize overview and summary slides to grasp broad topics.
• Review lecture slides and assigned textbook readings for additional context.
• Understand and compare concepts, such as metastable vs. dynamic equilibrium.

Earth System Science

• Focus on topics like human impact, open/closed systems, feedback loops, and equilibrium.

The Human Footprint

• Emphasizes sustainability across agriculture, energy, resources, and development.
• Examples include the impact of Belgian wind farms and deforestation in Rio de Janeiro.

Open vs. Closed Systems

• Open systems interact with their environment, having both inputs and outputs of energy and matter.
• Closed systems, like Earth regarding water and air, have limited resources and are relatively self-contained.

Feedback Loops

• Positive feedback amplifies changes, leading to greater deviations from the starting state, creating instability.
• Negative feedback moderates change, promoting stability and self-regulation within the system.

Equilibrium States

• Systems can reach equilibrium, maintaining balance over time.
• Types of equilibrium include:
  • Steady-state: Fluctuations around an average value.
  • Dynamic equilibrium: Changes in average values over time.
  • Metastable equilibrium: Resulting from abrupt transitions between states.

Earth's Axial Tilt

• The Earth's axis tilts at approximately 23.5° relative to the plane of the ecliptic, influencing seasonal changes.
• Earth's shape affects sunlight distribution, with sunlight spread over larger areas at the poles.

Milankovitch Cycles

• Variations in Earth's orbit and axial tilt affect climate and seasonal patterns over thousands of years.

Greenhouse Effect

• Longwave radiation from Earth is absorbed by greenhouse gases like CO2, H2O, and CH4, leading to increased atmospheric temperatures.
• Low, thick clouds generally cool the Earth by reflecting sunlight, while high, thin clouds trap heat.

Greenhouse Gases Sources

• Major sources of methane include rice cultivation, livestock waste, and fossil fuel usage.
• Nitrous oxide emissions are linked to motor vehicles and nitrogen fertilizers, with a long atmospheric lifetime of 121 years.

Residence Time of Gases

• CO2 has a prolonged residence time in the atmosphere, influenced by uptake rates from oceans, plants, and rock weathering.

Human Impact on Climate

• Current CO2 levels are historically similar to the Pliocene era (3-5 million years ago), when Arctic temperatures were significantly higher, and sea levels were notably elevated.

Heat Transfer Mechanisms

• Heat transfer occurs from hot to cold regions through:
  • Conduction: Direct transfer between molecules.
  • Radiation: Energy spread as electromagnetic waves.
  • Convection: Vertical energy movement in fluids.
  • Advection: Horizontal energy movement similar to convection.

Sensible vs. Latent Heat

• Sensible heat is the energy felt as temperature changes.
• Latent heat is the energy consumed or released during phase changes, such as when water freezes, releasing heat.

Principal Temperature Controls

• Key factors affecting temperature include:
  • Latitude: Distance from the equator.
  • Altitude/Elevation: Height above sea level.
  • Cloud Cover: Impacting solar radiation.
  • Proximity to Water Bodies: Water's specific heat moderates temperatures.

Prepare for your GEOG 102 midterm with this comprehensive review. The quiz consists of multiple choice and short answer questions focused on core concepts from lectures. Utilize the overview and summary slides to bolster your understanding and confidently tackle the exam.