Seasonal Variations in T°C, Pressure + Wind Belts

Question 1

How does latitude influence seasonal variations?

Answer 1

• at equator: angle of sun is high, so greater intensity of insolation is received so more heating (vice versa at poles)
• at equator: less atmosphere to pass through so less energy lost/scattered/reflected by atmo.
  
  • at poles: vice verses + albedo higher
• longer sun shines, more insolation received
  
  • polar regions: long days balance lack of intensity but long polar nights lose lots of energy

Question 2

How does land/sea distribution influence seasonal variations?

Answer 2

• land has lower reflectivity than sea, so more absorption of radiation (except ice)
• in land heat is confined near surface as it has poor conductors
• in sea sun rays penetrate deep, as it’s clear, distributing energy over a wider area
• land has a lower specific heat capacity than sea, so set amount of energy raises land T°C by more
• land has less water so less energy is wasted to evaporation

Question 3

How does ocean currents influence seasonal variations?

Answer 3

• surface ocean currents caused by prevailing winds
• clockwise in N. Hem, + anticlockwise in S. Hem
• water piles into domes + due to Earth’s rotation, water piles on W. edge of ocean basins
  
  • return flow = narrow, fast current (Gulf Stream)
• warm currents from near equator raise T°Cs near poles
• warm surface causes low pressure, so water moves from cold to warm + winds push warm into warm, exposing cold deep water. Process repeats