July 1, 2019.
70% of Earth’s fresh water is held in Antarctica ice sheet. If the sheet melts, it has the potential to raise global sea levels by 190 feet (Klekociuk and Wiennecke, 2016). As the climate changes, it is imperative that to understand precipitation systems of Antarctica in order to measure and predict weather around the world. One aspect of precipitation events that we do not understand fully in Antarctica is sublimation. Data was collected from four Ott Pluvio Precipitation Gauges with Belfort Double Alter Shields placed in and around the Ross Ice Shelf from November of 2017 to present. An R program was created to analyze and visualize periods of sublimation. A sublimation event was defined as a period at least 6 hours long that had statistically significant monotonic decreasing trend based on the Mann-Kendall Test. The rate of sublimation was then estimated using a Sen’s Slope calculation. Sublimation was detected in 60 to 70 percent of summer months and 30 to 40 percent in winter months, with median summer sublimation rates from .006 to .014 mm/hr and median winter sublimation rates from .003 to .006 mm/hr. Monthly sublimation spiked in the months of December, January, and February. These initial findings on Sublimation in Antarctica can be used to analyze the relationship between sublimation and wind, humidity, and temperature. Additionally, these sublimation estimates can be used in combination with precipitation time series to find the percentage of snowfall returning to the atmosphere via sublimation.
Applied Statistics | Environmental Monitoring
National Center for Atmospheric Research (NCAR)
The 2019 STEM Teacher and Researcher Program and this project have been made possible through support from Chevron (www.chevron.com), the National Science Foundation through the Robert Noyce Program under Grant #1836335 and 1340110, the California State University Office of the Chancellor, and California Polytechnic State University in partnership with NCAR. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the funders.