View Full Version : A question about seasons

2007-Jan-11, 04:37 PM
The northern and southern hemispheres on earth "mirrors" each others with respect to seasons (the northern winter is southern summer etcetera) - or so we may think. But not exactly, since in january earth is closest to sun, and the opposite is true in the beginning of july. Is there any significant effect (more extreme seasons on average in southern hemisphere?) Do the southern hemisphere "receive" more energy from the sound during an "average" year(if we for a moment assume it is constant)?
A question more: what does the difference in geography mean (the southern hemisphere is nearly covered by oceans and much of the rest is antarctic ice)?

Larry Jacks
2007-Jan-11, 04:52 PM
I've read that the sun is up to 6% more intense in the middle of a southern hemisphere summer than for the northern hemisphere. The fact that more of the southern hemisphere is water is significant. Temperatures tend to rise faster over land than over water.

2007-Jan-11, 05:03 PM
On account of the ocean influence, generally the southern hemisphere is cooler than the Northern one for any given corresponding latitude.

2007-Jan-12, 08:34 AM
I asked this question before. Agree with posts so far ie suns energy is more intense but temperature is moderated by latent heat capacity of the oceans. However, that said the increased solar radiation reaching the surface could explain the higher incidence of skin cancer in Australia.
Also would impact on the quoted output of any given solar panel whether sited in the northern or southern hemispheres.

Ken G
2007-Jan-12, 10:39 AM
I think the skin cancer rates are not as much affected by the 6% relative increase in summer heating rates in the southern hemisphere, as by the hole in the ozone layer over New Zealand and Australia.

2007-Jan-12, 03:56 PM
Yep, most sources I´ve read agree with that.

Spaceman Spiff
2007-Jan-12, 05:09 PM
And here (http://homepages.wmich.edu/%7Ekorista/aphelion.html) is a brief explanation that I've got posted on one of my intro astronomy course's websites.

Ken G
2007-Jan-12, 05:43 PM
That's interesting-- I hadn't appreciated how much more extreme are the seasons in the nothern hemisphere.