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Correlation Tests Between the Craven SigSvr Parameter and Severe Weather. Calvin Moorer EAS4803 Spring 09. Outline. Craven SigSvr Parameter Defined Data Source Plot with Linear Regression Pearson’s Correlation Coefficient Test Bootstrap Test of the Correlation Coefficient Conclusion.
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Correlation Tests Between the Craven SigSvr Parameter and Severe Weather Calvin Moorer EAS4803 Spring 09
Outline • Craven SigSvr Parameter Defined • Data Source • Plot with Linear Regression • Pearson’s Correlation Coefficient Test • Bootstrap Test of the Correlation Coefficient • Conclusion
Craven SigSvr Parameter • SigSvr = (mlCAPE J/kg)*(deep layer shear m/s) • CAPE(Convective Available Potential Energy) Measure instability and potential updraft strength • Deep Layer Shear- measures change in wind speed and or direction with height between 0-6km • Most significant severe weather events occur when the SigSvr Parameter exceeds 20,000 m3/s3. w1.spc.woc.noaa.gov
Data Source RUC-2 National Weather Service in Peachtree City
Linear Regression p = 0.0025 which is less than 0.05 Correlation is therefore significant.
Pearson’s Correlation Coefficient • corrcoef(x,y) x = SigSvr Parameter y = Number of Severe Weather Events ans = 1.0000 0.7283 0.7283 1.0000 • r = 0.7283 indicates a positive correlation
Bootstrap Test of Correlation Coefficient Average Correlation Coefficient r computed using the mean function yields 0.7246 in agreement with 0.7283
Conclusion • Linear Regression, Pearson’s Correlation Coefficient and the Bootstrap Test of the Correlation all prove that the Craven SigSvr Parameter correlates with the number of severe weather events. • The Craven SigSvr Parameter is useful in forecasting severe weather.