Atmospheric Heat Budget

Question 1

What is the radiation balance at the Earth’s surface?

Answer 1

• Surplus

- Due to axial tilt (Variation in degrees from equator) and albedo affect (Reflects energy at poles)

Question 2

What is the radiation balance in the atmosphere?

Answer 2

• Deficit

- Due to reflection off cloud cover

Question 3

What is the combined radiation balance?

Answer 3

• Earth transfer heat from areas of surplus to areas of deficit

Question 4

What changes in insolation can influence the heat budget?

Answer 4

• Build environment (Alter albedo and energy released from urban areas can cause ‘heat islands’)
• Ocean currents (Warm currents carry heat polewards to balance heat budget)
• Distance from ocean (Land and sea differ in ability to absorb and retain heat. Sea has greater specific heat capacity and regulates temps)
• Seasons (Hemisphere pointing towards sun will experience summer and most insolation)
• Prevailing wind (Temp of wind is determined by area of origin, wind blowing over sea will be warmer in winter)
• Cloud cover (Clouds reduce UV radiation, reduce daytime temps and retain heat at night)
• Altitude (Troposphere warmed by heat radiated by land and distributed by convection and conduction)

Question 5

How much heat transfer across the planet does oceanic circulation account for?

Answer 5

20%

Question 6

What is ocean circulation driven by?

Answer 6

• Temperature

- Salinity differences

Question 7

Outline oceanic circulation in the North Atlantic

Answer 7

1) SW prevailing wind causes surface current to move NE towards higher latitudes (Forms Gulf Stream)
2) Water sinks in far N. Atlantic as it becomes colder and more saline due to high latitude
3) Corresponding cold current travels south cooling east of Canada and northern USA (Labrador Current)