The general support for warming is based not so much on the quality of the data, but rather on the fact that there was a little ice age from about the 15th to the 19th century. Thus it is not surprising that temperatures should increase as we emerged from this episode. At the same time that we were emerging from the little ice age, the industrial era began, and this was accompanied by increasing emissions of greenhouse gases such as CO2, methane and nitrous oxide. CO2 is the most prominent of these, and it is again generally accepted that it has increased by about 30%.

The defining characteristic of a greenhouse gas is that it is relatively transparent to visible light from the sun but can absorb portions of thermal radiation. In general, the earth balances the incoming solar radiation by emitting thermal radiation, and the presence of greenhouse substances inhibits cooling by thermal radiation and leads to some warming.

That said, the main greenhouse substances in the earth's atmosphere are water vapor and high clouds. Let's refer to these as major greenhouse substances to distinguish them from the anthropogenic minor substances. Even a doubling of CO2 would only upset the original balance between incoming and outgoing radiation by about 2%. This is essentially what is called "climate forcing."

There is general agreement on the above findings. At this point there is no basis for alarm regardless of whether any relation between the observed warming and the observed increase in minor greenhouse gases can be established. Nevertheless, the most publicized claims of the U.N.'s Intergovernmental Panel on Climate Change (IPCC) deal exactly with whether any relation can be discerned. The failure of the attempts to link the two over the past 20 years bespeaks the weakness of any case for concern.

http://online.wsj.com/article/SB10001424052748703939404574567423917025400.html



That to me is eminently sensible.

What a hypocrite...
so some guy who takes photos is now an expert on global warming and climate change?

You keep missing the point Mozz...    no one is denying there have been rises in temperatures, just the mechanisms driving them, the long term effects and what we should and can do about them.

Poobaby...  as usual you miss the point too.  How unusual. 

Soren,

Do you want me to answer the rephrased question?

muso wrote on Apr 14^th, 2010 at 5:10pm:



Which / whose question was rephrased? how?

As always - yes please but only if you can convey the logic/concept of it first. Leave the details for/when they are needed.

See the other thread.

This conversation involving soren and I has no relevance to this thread, beo.

(Whereas any conversation between yourself and anyone has no relevance to anything.)

I only raised it here because soren was ignoring the other thread. See the other one.

Once more for the slow of wit: T h e   o t h e r   t h r e a d.

That was you in the parking fine video wasn't it?

T-H-E  O-T-H-E-R  T-H-R-E-A-D.

(And it's a hundred and sixty-five pounds you stupid f*ing woman!)

Once again:

In geological history there have been occasions where sharp rises in temperature were initiated and driven by large spikes in greenhouse gases, similar to the fossil fuel emissions spike of today. The Paleocene Eocene Thermal Maximum (PETM) is an example.

Roughly 55 million years ago, ocean pH levels dropped drastically (specifically due to CO2, as attested by sediment analysis) and global temperatures rapidly rose over 5 degrees. The resolution of available proxy records indicates that this occurred in a period of time no longer than 5000 years. It's not possible to know if it happened even faster. It could have. The likely cause was massive releases of methane from the ocean floors, perhaps due to some smaller warming or changes in sea level. It took over 100,000 years for the ocean, atmosphere, and temperatures to return to their previous state. The result was a mass extinction event that took millions of years to recover from.

Another example was the massive volcanic eruption of the Deccan traps around the end of the Cretaceous Period (around 65 billion years ago).  This was a basaltic eruption of massive proportions (a sizeable part of India). It released vast quantities of CO2, but no significant levels of particulates or SO2. Basaltic eruptions tend to be much less violent than Acid (eg Rhyolitic) volcanoes (such as Mt Pinatubo). The lava is much more liquid (less viscous) and there is no pressure build up and subsequent explosion, as is associated with the latter.