Naked Science Forum

Life Sciences => The Environment => Topic started by: Pat Bar on 22/04/2009 13:30:02

Title: What happens to the heat from the Sun that warms Earth?
Post by: Pat Bar on 22/04/2009 13:30:02

Pat Bar  asked the Naked Scientists:
   
Dear Chris,
been listening to your interviews on the 702 in SA on internet radio.
It is wonderful and really interesting stuff thanks.

I was wondering how come the sun can heat the earth up so much, where does the heat go to, does it go up into the atmosphere and bleed off into space? Or does it go into the earth to the molten part of the core, is this the occasional volcanic eruptions at times?

best regards
Patrick Barclay

What do you think?

Title: What happens to the heat from the Sun that warms Earth?
Post by: Karsten on 25/04/2009 14:00:00

I would say ultimately it is radiated into space. Visible light from the sun is transformed into infrared light on this planet. It bounces around a while here and then leaves us. You turn of the sun - we get pretty darn cold fast here on Earth.

Title: What happens to the heat from the Sun that warms Earth?
Post by: paul.fr on 27/04/2009 04:23:29

Pat, you may find the following links useful:

www.nasa.gov/pdf/135642main_balance_trifold21.pdf

Quote

The Balance of Power
in the Earth-Sun System
The Sun is the major source of energy for Earth’s oceans, atmosphere, land, and biosphere. Averaged over an entire year, approximately 342 watts of solar energy fall upon every square meter of Earth. This is a tremendous amount of energy—44 quadrillion (4.4 x 1016) watts of power to be exact. As a comparison, a large electric power plant produces about 1 billion (1 x 109) watts of power. It would take 44 million such power plants to equal the energy coming from the Sun.

With all that energy out there, it seems as if Earth should just keep getting hotter. Why doesn’t this happen?
At the same time the Sun’s energy heats the planet, the planet radiates energy that we can’t see with our eyes (longwave radiation or heat) back to space. As an object heats up, it starts to dramatically increase the amount of heat energy it gives off. So the more Earth heats up, the more rapidly it will lose energy to space.

and this:
http://www.physicalgeography.net/fundamentals/7m.html

Quote

CHAPTER 7: Introduction to the Atmosphere
 
(m). Global Surface Temperature Distribution
 
If the Earth was a homogeneous body without the present land/ocean distribution, its temperature distribution would be strictly latitudinal (Figure 7m-1). However, the Earth is more complex than this being composed of a mosaic of land and water. This mosaic causes latitudinal zonation of temperature to be disrupted spatially....

just click the links for the full text.

Title: What happens to the heat from the Sun that warms Earth?
Post by: paul.fr on 27/04/2009 04:26:07

This third link is also about the radiation balance and climate change:
http://co2now.org/index.php/Know-the-Changing-Climate/Climate-System/ipcc-explains-earths-climate-system.html