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4.1 Intro to Water System - Coggle Diagram

- - - - Melting polar ice: Increased temperatures cause polar ice to melt, releasing large amounts of freshwater into oceans. Freshwater dilute ocean salinity (reducing the saltwater density) & reduce the sinking of saltwater in the poles, slowing down downwelling & OCB as salinity difference between oceans is reduced.
      - Warming oceans: Ocean temperatures increased, especially in areas near the poles (deepwater currents affected). When the ocean in polar regions becomes warmer, difference in temperature between poles & equator becomes less slowing down OCB. Additionally, increased surface temperature in the polar regions slows the downwelling of cold water.
      - Disrupt global climate patterns: If OCB slows down or stops, it could lead to significant shifts in global climate.
        
        Example: Western Europe regions may experience colder temperatures despite global warming because the warm currents that moderate their climate slowed down, weakened or disappeared.
    - - Cold, salty water sinking: In polar regions, water becomes colder & saltier due to freezing & evaporation, causing it to become denser
        (due to more salinity or less temperature) & sink to the ocean floor (downwelling).
        
        Deep-water circulation: The dense, cold water moves along the ocean floor towards the equator, where it slowly rises as it warms (upwelling) due to change in density (high temperature less dense).
        
        Surface currents: Warm water from the equator travels towards the poles, replacing the cold water that sank, forming a continuous loop.
      - Circulation is crucial for distributing heat, nutrients, & gases like oxygen around the globe, helping regulate Earth's climate.
    - - transport oxygen-rich water to deeper parts of the ocean, supporting life at greater depths.
    - - zones are highly productive areas for marine life because the nutrients brought to the surface support the growth of phytoplankton, which forms the base of the marine food chain.
  - - - Global Conveyor Belt
        
        Driven by water density that is heavily dependent on temperature and salinity
        
        temperature: colder more dense; hotter less dense
        
        Salinity: greater salinity, more dense; lower salinity, less dense
        
        Warm ocean current move water
        away from equator towards pole.
        
        Cold ocean current move water away from cold region towards equator
        
        The warm Gulf Stream transport warm current from Gulf of Mexico to towards North West Europe to temperate land instead of sub artic
        
        The cold Peru current bring nutrient rich water dragged to the surface by offshore wind
    - - Temperature
        
        Variation: Higher in tropical and subtropical areas due to insolation
        
        Depth Profile: Declines steeply from 300-1000 meters, then decreases uniformly below 1000 meters (thermocline).
        Density:
      - Density
        
        Relationship with Temperature: Warmer water is less dense, while colder water is denser.
        
        Relationship with Salinity: Higher salinity increases density.
        
        Vertical Distribution: Cold, highly saline deep water is denser than warm, less saline surface water.
        
        Ocean Circulation: Differences in density drive the ocean conveyor belt.
      - Salinity
        
        Concentration: Higher in warm seas due to high evaporation rates.
        
        Influences: Runoff from rivers reduces salinity, while thawing of icebergs decreases it and freezing increases it.
        
        Trend: Increases with depth.
- - - - Kinetic/ wind energy moves clouds (from over land, usually)
        
        Solar energy melts ice producing streams/ lakes/ rising ocean levels
        
        Solar energy causes both transfer (eg advection) and transformation (eg evaporation) in hydrological cycle
        
        Precipitation/ run-off/ streamflow occurs due to gravitational energy/ difference in potential energy between the high and low positions
        
        Transpiration is driven by opening of leaf stomata which is due to chemical energy (cellular respiration in mitochondrion)