Bazz: "If human activity is such a large influence then why has it not been able to overpower the slight decrease in global temperature that has been experienced in recent years and so force significant temperature rise?"

You are just repeating the same question you asked above (Thursday, 28 August 2008 7:47:04 AM) that was already answered. Your argument is equivalent to saying that the sea level isn't rising, by looking only at a low tide. We are at a trough in the 11 year solar cycle. See NASA:
http://data.giss.nasa.gov/gistemp/2007/
It hasn't stopped the alarming rate of reduction of global ice and glaciers, and the melting of the permafrost, warming of the oceans, and other longer term effects.

No Sams it is not the same question and I am still looking for an
answer to the first question;

However there does seem to me to be a question over what proportion
of global warming is caused by human activity ?

If global warming was such a panic stations matter then it should not
have been brought to a grinding halt by a couple of months of near
zero sunspot counts.
I hear tell that there has been a single next cycle sunspot seen so
maybe we are about to get off the bottom.
Radio condx to Europe are noticeably better today so maybe the
temperature will rise soon.