The Big Idea: How Climate Projections are Made
Friday, December 14th, 2018
How do scientists roughly predict the climate in 50 or 100 years?
- Teams around the world have developed over 30 complex mathematical models to simulate the interconnected workings of Earth’s atmosphere, land, oceans and ice sheets.
- They use the models’ projections based on different trajectories for the concentration of greenhouse gases in the atmosphere to gain an idea of how different levels will affect the future climate.
How did we refine projections for Indiana’s climate?
- Each model represents the world in a different way. The Indiana Climate Change Impacts Assessment (IN CCIA) team chose 10 models that capture the range of model variability and best represent historical changes in the Midwest.
- Indiana projections used the “high” and “moderate” trajectories of greenhouse gas concentrations adopted by the Intergovernmental Panel on Climate Change. High represents a scenario where we use fossil fuels until the end of the century; medium, a future where we rapidly limit use of fossil fuels.
- The team then used statistical downscaling to make more finely calibrated projections, using 98 years of regional meteorological data.