The Global Heat Budget
Aim- To describe and explain the global heat budget.
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Read pp8 of the Physical Core textbook.
Complete a copy of the diagram below.
Write out a definition of (i) conduction (ii) latent heat.
In what ways is heat transferred at the surface?
Using figures 1.7 describe and explain the global heat budget. 12 marks
7%
7%
7%
A 14%
B 10%
46 % absorbed at the surface
C 22%
KEY
A=
B=
C=
Heat is transferred at the surface through a number of processes;
14% is transferred by re-radiation, however of this 14%, 7% is lost to space.
10% is returned to the atmosphere through conduction,
this is where the air comes into contact with the earth’s surface and is heated.
22% is transferred by latent heat,
whereby water is evaporated from the earth’s surface, rises and when condensing takes place
returns the heat to the atmosphere.
The Global Heat Budget
Aim- To describe and explain the global heat budget.
• 100% enters the earth/atmospheric system. 23% of
those is initially absorbed by the atmosphere, 4% by
clouds and 19% by water vapour, gases and dust. 25 %
is also reflected by atmosphere, 17 % by clouds and 8%
by gases and dust. This leaves 52% heading towards
the earth’s surface, where 46% is absorbed by the
surface and 6 % is reflected. The total energy lost at this
point is 31% known as the earth albedo (total amount
reflected). The 46 units absorbed at the surface are then
transferred back into the atmosphere through a range of
processes; 14% is re-radiated (7% into the atmoshere
and 7% into space), 10% is conducted and 22% is
transferred through latent heat (energy released when
evaporated water condenses in the atmosphere).