Sarah Maddox Under Hamish Gordon, Jasper Kirkby University of Michigan CERN REU Design of Experiments for the 2015 CLOUD Run

CLOUD Experiment The CLOUD chamber simulates cloud formation We would like to know Earth’s climate sensitivity, but the effect of clouds is highly uncertain J rate = rate of nucleation Affected by sulfuric acid concentration, ammonia concentration, organic molecules, amines, temperature, ionization (from GCR and Proton Synchrotron) Source:

Design of Experiments How do seven such parameters affect nucleation rate? Maximin Latin Hypercube Sampling The Kriging Model: A Gaussian process emulator A simple Latin Square 2D Kriging Model Interpolation The height of the red dot is interpolated from the surrounding points Source:

J Rates [4D] using Latin hypercube sampling and a known parameterization

Plans for the Future Add more variables (dimensions) to sample the 7D space cleverly Once I have a design data set in 7 dimensions (preferably about 50 data points), I will build an emulator to predict the rest of the points in 7D space. In the fall, 50 experiments will be run at these conditions, which can then be input into the model to predict the nucleation rates across the space.

Thank you!