I have spent a considerable amount of time talking about global warming and related subjects, but I have yet to really talk about the other side of the argument. I only think it’s fair that both sides be stated. There are those who are skeptical about the seriousness or even the existence of global warming, making arguments that range from claiming that there is no direct link to humans contributing to rising global temperatures to the date gathered is forced, incomplete, and even inaccurate.
Let me just say that I am in agreement with the majority of scientists and with the mounting data being collected stating that global warming is a real and serious threat that needs to be handled now before it’s to late to do anything about it. The skeptics are in denial, due to political or economic reasons, and they refuse to engage properly in the debate by acknowledging the evidence of the opposing side. So in order to make sense of what the skeptics are claiming, I will line their argument up with the scientific consensus so that way it will be clear what the skeptics are responding to in their claims and just what evidence they are overlooking when they claim such things.
The Basics
So basically the skeptics claim that there is no credible evidence to suggest that humans are connected with global warming (if global warming is happening at all that is). They then go on to claim that all the evidence is circumstantial in its attempt to connect rising temperature with carbon dioxide (CO2). As I stated before, this belief goes against the scientific consensus with no prominent and qualified member of the scientific community saying otherwise. 
However, there are those who, both in the public and scientific community, speak out against the consensus. Donald Trump has stated that he does not think global warming is real, using snow and cold winters as evidence. Other deniers can be found in such field as architecture (when it comes to the need for green buildings) and weather forecasting (around 25% or local forecasters claim global warming is a myth). Despite these denials, the overwhelming majority is in agreement that this is a real problem, and that majority includes the people who matter (the experts who dedicate their careers to understanding climate).
The Debate
Skeptics argue that by looking at this graph, it is clear that CO2 levels do not match up with rising temperatures (or at least not always which is enough to establish reasonable doubt). The consensus on the other argues that single graph from a small area cannot possibly demonstrate evidence on a world-wide scale. They continue to argue that CO2 rises have happened previous to temperature rises in the past, so that lag cannot link CO2 to temperature rises. The consensus claims that this is a misinterpretation of their data. They are claiming that CO2 is speeding up temperature rises currently, not claiming anything about the past.
Skeptics also point out that the vast majority of temperature records are from land-based stations, leaving 70% of the world’s surface unrecorded. Since cities and town raise the temperature due to the “urban heat island effect”, the data cannot be trusted. The scientific consensus, however, is aware of such a phenomenon and has taken into account its effects, applying filters against such distortion. There is another phenomenon that the skeptics cling to that’s called the “Medieval Warm Period”. This period during the medieval times was actually recorded to be warmer than current day, long before humans started to expel CO2 into the atmosphere. They claim that this is further proof that CO2 and temperature rises are not connected to one another. The consensus responds to this by arguing that it was only a local warming, not a global warming, meaning the two are very different. They use ice core data to demonstrate that temperatures varied between warm and cold around during this period. Furthermore, there is not enough evidence to support the skeptics belief. In response to the consensus’s rebuttal, skeptics dismiss the evidence from ice cores as being unreliable, and of course the consensus argues against this dismissal.
Then there is always the attacks thrown but the skeptics. They claim that data has been forged or distorted in order to support the argument of the consensus. If something does’t exactly fit, the evidence is edited so that it does. They also believe that there is a conspiracy between the top climate scientists to hide and distort data. This of course is not true. If data is edited is it for reasons such as the correcting of pervious results whenever new evidence is discovered, and such conspiracy theories between respected scientists have no proof.
In conclusion, the debate comes down to the skeptics arguing that CO2 is not connected to global warming, if global warming is happening at all. Global warming is nothing but a conspiracy to raise fear and all its supportive data is unscientific and biased.
Sources
http://www.informationisbeautiful.net/visualizations/climate-change-deniers-vs-the-consensus/
http://www.mnn.com/earth-matters/climate-weather/photos/7-surprising-global-warming-deniers/nonbelievers
http://en.wikipedia.org/wiki/Climate_change_denial