Despite the abundance of evidence that exists to prove that climate change does exist, there are still scientists and scholars who are skeptical about the claim. A major argument against climate change existing is that climate has changed before so human beings cannot be the reason for climate change - 33% of Americans agree to this statement ("Americans’ Knowledge Of Climate Change"). This is true that the climate has changed before. Greenhouse gases were involved in most of the climate changes in Earth’s history. When the gases in the Earth’s atmosphere were reduced, the climate on Earth became colder. When these gases were increased, the climate became warmer. Mass extinctions have even occurred as a result from global warming that was caused …show more content…
A climate model can be defined as a “mathematical representation of the climate system based on physical, biological and chemical principles. ("Introduction To Climate Dynamics And Climate Modelling - What Is A Climate Model ?")” Climate models of course have to be tested to see if they work. All models are generally tested in a process called ‘Hindcasting’. In the test, loosely estimated inputs for past events are entered into the model to see how well the output matches the known results. If the model gets the past right, there is good reason to think that the models future predictions are right as well. Scientists have tested models against the current records that suggest that carbon dioxide must be the cause of global warming. These models could not reproduce records that suggest the Earth is warming without taking rising carbon dioxide levels into account. Another example of a successful climate change model predicting a climate change is shown in a paper done by James Risbey in 2014. In his study, he looked at each 15 year period since the 1950s, and compared how accurately each climate model simulation had represented El Nino/La Nina conditions during those 15 years. The El Nino events are the warming of the tropical Pacific, while the La Nina events are the cooling of the tropical Pacific ("What Are El Niño And La Niña Events?"). He found that when the climate models were synchronized with the El Nino/La Nina Cycles, the climate models had accurately predicted the global surface warming (Nuccitelli), concluding that “the projections well estimate the observed trends for all 15-year periods over the past half-century” (Risbey). Another example where climate models were accurately able to predict future climate systems was the eruption of Mt. Pinatubo - an active volcano in the Cabusilan Mountains. The climate models had successfully predicted the climate response