The studies yielded strikingly similar results, with the main difference being that one study used Celsius while the other used Fahrenheit to predict temperatures.
One of the studies, titled "Less than 2 Degrees Celsius Warming by 2100 Unlikely" and led by researchers at the University of Washington, used statistical tools and analysis to show that there is a 95 percent probability that the Earth's temperature will increase by more than two degrees by 2100 and a 1 percent probability that it will be at or below 1.5 degrees Celsius. The researchers used three factors to estimate future emissions: the total human population of earth, the gross domestic product per person, and carbon intensity, which is the amount of carbon emitted per unit of energy consumed.
"The likely range of global temperature increase is 2.0 to 4.9 [degrees Celsius] and our median forecast is 3.2 Celsius. Our model is based on data which already show the effect of existing emission mitigation policies. Achieving the goal of less than 1.5 Celsius warming will require carbon intensity to decline much faster than in the recent past," said Adrian Raftery, the primary author of the University of Washington study. This means that a two-degree Celsius rise is the favorable outcome; there is a 90 percent probability of temperatures increasing from 2 to 4.9 degrees Celsius.
The second study, "Committed Warming Inferred from Observations," authored by researchers at the University of Colorado and the Max Planck Institute for Meteorology in Hamburg, Germany, reviewed historical greenhouse gas emissions. The study determined that even if we all stopped burning fossil fuels today, the Earth's temperature would still increase by approximately 2.3 degrees Fahrenheit by the end of the century. According to the study, if greenhouse gas emissions continue to be produced at the existing rate for another 15 years, there is a 13 percent chance that global temperatures will rise by 3 degrees Fahrenheit, regardless of future greenhouse gas emissions.
"This ‘committed warming' is critical to understand because it can tell us and policymakers how long we have, at current emission rates, before the planet will warm to certain thresholds. The window of opportunity on a 1.5-degree [Celsius] target is closing," Robert Pincus, an author of the second study, said in a statement.
Although both studies anticipate a grim future in terms of global warming, they do not account for every factor. Further investing in solar power and alternative sources of energy, as well as implementing the appropriate public policies for such alternative energy industries to thrive, will be key in the fight against global warming.