CISL Visitor Program (CVP) Brown Bag Seminar: "Statistical Analysis of Compressed Climate Model Data"

08/10/2018 - 12:00pm
ML Chapman Room

"Statistical Analysis of Compressed Climate Model Data"
 
Joseph Nardi and Noah Feldman
Carleton College
 
The data storage burden resulting from large climate model experiments only continues to grow. Lossy data compression methods are promising to alleviate this burden, but lossy methods introduce the possibility that key climate variable fields could be altered to the point of affecting scientific conclusions. It is therefore important to develop a detailed understanding of how compressed climate output differs from the original for different compression algorithms and compression rates. In this work, we evaluate the effects of two leading compression algorithms, zfp and sz, on daily and monthly temperature and precipitation data from the CESM Large Ensemble Project (LENS). While both algorithms show promising fidelity with the original model output, small but detectable artifacts are introduced even at low compression rates. Examples include biases in temperature gradient fields and seasonal cycles and the number of rainy days. We will discuss some of our key findings and highlight the need for evaluation methods that are sensitive to errors at different spatiotemporal scales and specific to the particular climate variable of interest.
 
Friday, August 10, 2018
12:00 p.m. - 1:00 p.m.
Mesa Lab, Chapman Room
Bring your lunch!