An Evaluation of the Antarctic Mesoscale Prediction System using Unique New Data from the CONCORDIASI Field Program
This study focuses on establishing and diagnosing the errors in AMPS by comparing the forecast soundings at different lead times against dropsonde observations made during CONCORDIASI. Interpolations to model eta coordinates and pressure levels provided a basis for analyzing the data through all levels of the troposphere as well as the lower stratosphere. A statistical analysis discovered substantial issues including consistent 1-2-K positive temperature biases and 3-4-K positive dew point biases at the surface during lead times ranging from 12-108 hours. Proposed causes of these errors include the radiation and snow parameterization schemes. An investigation using the Rapid Radiative Transfer Model is planned. In addition, vertical transport of moisture also appears to be an issue with large dew point biases of over 5 K and low correlations in the upper atmosphere. No substantial biases in the winds have been found. Further plans include a spatial analysis by surface characteristics and a comparison to the European Centre for Medium Range Weather Forecasting's operational global model to establish the benefit of LAM's in the Antarctic.