The Cooperative Institute for Climate, Ocean, and Ecosystem Studies

Hi, my name is Nico Davis. I am a junior at Colorado College studying environmental science and mathematics. Over the course of the Summer I worked with my Mentor Matt Loungo, a postdoctoral fellow and Edward Blanchard a University of Washington research scientist. We Investigated model-observational disagreements within the Community Earthsystem Model version two (CESM2) particularly in the southern ocean.

CESM2 is able to accurately reconstruct sea surface temperature (SSTs)  almost everywhere except for the southern ocean. During the past 40 years the southern ocean has experienced a SST cooling that was not predicted by CESM2. My project sought to explore this disagreement through the analysis of CESM2 output.

Initially my focus was familiarizing myself with the NCAR derecho supercomputer, bash coding, and data preprocessing. CESM2 output comes in massive files so I had to trim the data before I could load it into python and benign visualization. After preprocessing, I could begin to make sense of southern ocean climate by plotting mean state SST and SST trends. I also plotted different variables like westerly wind stress, salinity and subsurface temperature to gain a more nuanced understanding of the difference between the predicted and observed climate.

Our team also sought to compare a wind column nudging experiment to a wind stress overriding experiment in order to learn more about the physical dynamics of the southern ocean SST. By plotting its output, I determined that the  wind column nudging experiment was not able to reconstruct westerly surface wind stress thus it is not an appropriate tool for analyzing long term trends. Because of this result I shifted my focus to the analysis of the CESM2 large ensemble. By analyzing the range of outcomes for each of the 100 model runs I found some models were able to reconstruct SST trends  far more accurately. Continued work will seek to understand the factors involved in yielding a successful model run.

The program was an immersive experience in research. I learned what it was like to have  my own research project, as well as attend seminars, meetings in the Oceanography and Atmospheric Science Departments and attend PhD defenses. I learned valuable coding and data analysis skills, and I feel proud to be pursuing a first author publication with the support and guidance of my mentor, who I will continue to work with.

Project Introduction

Research Poster