Does the melting out of old stumps in Greenland prove man-made global warming today?

Question

I saw on another comment forum a guy who said he saw on TV some old stumps in Greenland, dated 7000 years go, just melting through the ice.

He said this was shown to prove global warming is so bad all the old ice is going also.

Now, I am wrong to say that this really proves a natural global warming ending 7000 years ago with the trees of an ancient forest killed by the cold, and thus showing natural global warming even farther back, far enough before that a large forest had time to become established and grow up...a natural warm cycle warmer and longer than the present?

Does this mean that the present cycle is man-made, as he claimed, and was not refuted, or does it mean what we have now is something that has happened before, and probably more so, since it was warm enough long enough to grow large trees in forest. Means the ice had to be gone, pretty much, for a forest to grow. And since it is only beginning to melt out, probably was hotter than now when it was growing.

Bob ..

Just through one of the more agressive solar cycles that I have seen, and yet it has no effect...and the little ice age when sunspots quit is just a coincidence?

Campbelp ..

Well said.

Answer 1

It proves there is warming. It doesn't prove anything about the cause. It does not prove the warming is man made and it does not prove it is natural.

Answer 2

As Campbelp and Bob have both said, it doesn't prove actually anything in itself other than that the ice is melting, there could be any one of a number of reasons for this. Sometimes factors unique to a specific area can cause localised warming or cooling, sometimes the effect is on a larger scale.

Ice is retreating almost everywhere on the planet, from Glacier National Park to the Himalayas, from the Arctic to the Antarctic. This tells us that something is happening but it doesn't provide answers to the whats, whys and hows. These answers are only provided through technical and scientific studies.

It's not just Greenland that has trees underneath the ice, this is found all over the planet and again, the explanations can be due to local or global factors.

In the past the planet has been much warmer than it is now, at one time trees grew almost everywhere and with the coming and going of ice ages they've been burried and then subsequently re-emerged.

Greenland is an interesting place to study because historical events there do not match the global picture. The main change been a movement in the North Atlantic Conveyor - the ocean current that carries warm water from the Carribean to the North Atlantic. It ensures that places like Greenland have a warmer climate than they would otherwise.

The current drifts about and the climate of Greenland (along with parts of Northern Europe) is greatly influenced by this. It means that, for example, Greenland can be warming whilst the rest of the world is cooling and vice versa. This has happened several times in the past, the trees are the ancient remnants of a time when Greenland was considerably milder than it is now (at the moment the UK is the prime beneficiary of the Atlantic Conveyor and temps here are warmed by 7°C as a consequence).

Answer 3

It's not really proof, one way or another.

First, no one disputes that climate changed naturally before, mostly by the Sun. We've measured the Sun for a long time now, and we know that it's not the cause of the PRESENT warming.

http://news.bbc.co.uk/1/hi/uk/6290228.stm

Second, things vary from place to place around the world. What happens in any one place proves little.

The bottom line:

"While evidence suggests fluctuations in solar activity can affect climate on Earth, and that it has done so in the past, the majority of climate scientists and astrophysicists agree that the sun is not to blame for the current and historically sudden uptick in global temperatures on Earth, which seems to be mostly a mess created by our own species."

http://www.foxnews.com/story/0,2933,258342,00.html

EDIT - What scientists think is important is the amount of energy the Sun is radiating, Total Solar Irradiance. It's not clear how having more or less sunspots could affect temperature. And the number of sunspots does not match up with the temperature data. More here:

http://environment.newscientist.com/channel/earth/climate-change/dn11650
http://www.nature.com/nature/journal/v443/n7108/abs/nature05072.html
http://stephenschneider.stanford.edu/Publications/PDF_Papers/DamonLaut2004.pdf