Why are these 2 graphs so smilar, and what do they tell us?

Question

http://data.giss.nasa.gov/gistemp/graphs/Fig.A3.lrg.gif

http://data.giss.nasa.gov/gistemp/graphs/Fig.A4.lrg.gif

Answer 1

Earth's northern hemisphere contains most of the land and most of the human population (about 90%).

Answer 2

It tells us that our global temperature is definitely getting warmer in the course of time.

Answer 3

It tells me a couple of things that I already know.

1) That the Southern hemisphere is mostly water

2) The oceans are cooling off.

This is also what keeps our planet from ever having runaway global warming whether its caused by nature or contributed to by man.

Now couple the oceans cooling off with a less active sun cycle and you will start seeing the heat of the land graph start to climb downwards.

Alex: Pull out a map of the world or even a globe and you will see that there is significantly more water mass than land mass in the Southern hemisphere. Here all help you:

http://www.nationalgeographic.com/xpedit...

Answer 4

obviously the data is irrelevant.

it tells us what we want to hear.

oh, and stop trying to educate the terminally intellectually deficient.

too bad Densa doesn't recruit here.

they'd make a killing.

Answer 5

As there are more pirates in the northern hemisphere, we can conclude that pirates are responsible for global warming.

Answer 6

Both graphs show the difference in temperature (temperature anomaly)  from the long term average (typically this is the 30 year running mean temperature).

First graph shows the annual and 5-yr running mean anomaly temperature.  As many people have already pointed out, most of the and land area in in the northern hemisphere.  Land more quickly responds (absorbs shortwave and releases long wave) radiation - heat) than water does so where there is more land, there is more heat. and more temperature variation.  This in part causes the northern hemisphere to have more variation than the southern. The 5 year running means (solid line) reduces the variation some so that clear 5 year trends can be seen.   We can kind of see a reduction in air temps from ~1940 until ~1970 but the temps at there lowest are higher than those around 1900.  To find the causes, you might look to see if there were any significant aerosol sources (volcanic activity for example), or solar cycles around then.  But we can't tell the causes from the graphs, just that the long term trend looking at the graph overall) tends to indicate an increase in air temp.

The second graph shows the moderating effects of the oceans. Water tends to heat more slowly and release heat at a slower rate than land.  That's why the ocean temperature anomalies tends to be less variable than land temperature anomalies .  The oceans are a source of heat during cold periods and a source of cool during hot periods.  The graph shows that both land and ocean temperature have tended to rise since 1880, with the ocean temperature rising at a slower rate (as expected) than land temperatures.

Also, the oceans/land graph shows the same cooling between 1940 and 1970 for land and sea.  This I think corresponds to a reduction in hurricane activity for that period.  We have had reduced activity hurricane activity for a while and scientist are still trying to understand the relationships between hurricane numbers and strength and ocean and air temperatures.  Some say to expect stronger storms by not an increase in numbers, others same more storm, some say we won't be any different than "normal" (pre-lull numbers and intensities). The records don't go back far enough define the relationship statistically.  Models will again have to be used and corrected as more information and evidence is collected.

Answer 7

What people say about there being more oceans in the SH is bogus: the sea is warming FASTER than the land in the SH but much slower in the north. Slower warming in the south has nothing to do with oceans.