The site is called Skeptical Science because true science is indeed sceptical, and so John applies this to common "scepticism" about climate change, in order to see where the balance of evidence from the best research lies (see here for a good intro to the idea behind the site). If you have specific arguments that you've come across that seem to "disprove" climate science, here are 122 common sceptic talking points each answered in a single sentence (with links to longer answers). If you are yourself sceptical of the science of climate change, then make sure you read through the list and see if your reasons are already answered in the scientific literature. If you come across people putting forward arguments on other websites, bookmark this page and point people towards it.
Each answer refers to relevant scientific literature for those who want to take the discussion further. John is in the process of turning all his answers into three levels of readership: beginner, intermediate and advanced. The website is also being translated into numerous languages. All this work is done by volunteers, who have come across the site, found it a very useful resource and want to make it even more useful. Neither John nor any of his contributers are paid for what they do (apart from the odd PayPal donation); the site is a true labour of love.
Indeed, John has been quite open about the fact that he is concerned about climate change out of Christian love for his neighbours (especially the poor and future generations). He is doing an excellent job co-ordinating an increasingly popular, complex and useful website (which is now also a free iPhone and Android app) and he does it for love, not money. Praise God for John Cook!