BBC News - The arguments made by climate change sceptics

So what are their arguments, and how are they countered by scientists who assert that greenhouse gases, produced by human activity, are the cause of modern-day climate change?

Bjørn Lomborg: Global Warming and Mt. Kilimanjaro - WSJ.com

Climate activists claim the receding ice is evidence of the need for developed countries to reduce carbon output. Actually, the glaciers on Mount Kilimanjaro have been receding since 1890, according to research by G. Kaser, et al., published in the International Journal of Climatology (2004). They note that when Ernest Hemingway published "The Snows of Kilimanjaro" in 1936, the mountain had already lost more than half its surface ice area in the previous 56 years. This is more than it has lost in the 70 years since.

According to this study, and another published in Geophysical Research Letters (2006) by N.J. Kullen, et al., the reason the ice is disappearing is not warming temperatures, but a shift around 1880 toward drier climates. What we see today is a hangover from that climactic shift.

Climate change: rhetoric boils over

While the sun's energy does drive earth's climate, there are still questions are to whether solar disturbances do have an impact on our weather. Most scientists argue that the impact of these disturbances are minimal.

"Top" scientists unite to challenge rising tide of climate scepticism - Scotsman.com News

In a joint statement, the Met Office, Royal Society and Natural Environment Research Council said they "cannot emphasise enough the body of scientific evidence [what, specifically, is that evidence?] that underpins the call for action".
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They added that, since the IPCC presented "unequivocal" proof of a warming climate two years ago, the evidence had strengthened [specifically how?].