07.1 Hydrological Cycle

Mid-Course Check-In

  • Reminder of course objectives and progress.

  • Group quiz to assess understanding and retention.

  • Opportunity for student feedback (via Menti).

Advice for Second Assessment

  • Guidance provided to improve performance on the upcoming assessment.

Systems in Physical Geography

  • Emphasis on understanding systems approach using the hydrological cycle as a primary example.

    • Landscapes are interconnected through stores, fluxes, and connections.

    • Classification into categories: Ocean, Atmosphere, Terrestrial.

  • Discussion on significant systems in Physical Geography:

    • Ecosystems

    • Biogeography

    • Biogeochemical cycles

    • Interconnected nature of the natural environment.

Hydrological Cycle Overview

  • Central to Physical Geography, linking to global systems (energy, climate, sea-level change).

  • Comprehension of key stores and fluxes is essential.

  • Recognizing the cycle's relevance to topics such as:

    • Global energy systems

    • Climate dynamics

    • Palaeoclimate reconstruction.

Importance of the Hydrological Cycle

  • Described as a massive material circulation on Earth.

  • Integrates with global systems affecting landforms and climate.

  • Impacts observed at both regional and local scales.

Simplified Model of the Hydrological Cycle

  • Visual representation (Petersen et al., 2011).

  • Groundwater importance highlighted.

Turnover Times and Non-Ocean Storage

  • Effects of glacial climate on hydrological cycle rates discussed:

    • Current water locked in glaciers: 26M km³ = 65m sea level.

    • Historical data: 77M km³ = 197m sea level 20,000 years ago.

  • Key processes include:

    • Evaporation and transpiration

    • Sublimation

    • Condensation and precipitation.

  • Examine transfer of energy with water.

Global Energy Transfer System

  • Hydrological cycle's role in Earth's energy balance:

    • Insolation greatest at the equator; drives heat transfer.

    • Influences distinctive climate zones and weather patterns.

  • Patterns of rainfall:

    • Tropical regions

    • Desert areas

    • Polar fronts.

Case Study Example: Stable Isotopes

  • Stable isotopes provide insight into climatic changes across glacial and interglacial periods.

    • Heavier values associated with greater ice on land.

  • Variability seen in ocean and ice-core records.

Closing Thoughts

  • Hydrological cycle's connections with global systems (ocean circulation, biogeochemical cycles).

  • Importance of understanding stores, fluxes, and processes within the cycle.

  • Climate change's potential impact on the hydrological cycle to be examined in future topics.