US 7,069,258 B1 · Weather prediction method for forecasting selected events

Abstract

The invention provides methods, systems, and computer program products for short term probability forecasting of selected weather-related events. These embodiments are adaptable for any geographical region that can be identified and for which a reasonable number of data points exist. The inventive method uses a data set of n observations of m parameters, where the parameters may be statistically correlated. A Principal Component Analysis may be performed, with the data set as input, to provide a reduced set of principal components that are uncorrelated and account for most of the variance in the input data set. An orthogonal transformation may be performed on the reduced set of principal components to provide a rotated set of principal components that are aligned with the corresponding parameters in the input data set. Finally a logistic regression may be performed on the rotated set of principal components to derive an S-shaped predictive equation for the probability of a binary weather-related event of interest. An illustrative embodiment of the invention is given for forecasting the probability for the number of lightning flashes exceeding a selected value, for the western United States climatological area.

Claims16

Dependent claims

A method of predicting the occurrence of a selected weather event, the method comprising the steps of:

identifying a first set of parameters that relate to the selected weather event, wherein the parameters in the first set are statistically correlated;
identifying a data set comprised of a plurality of observations for the weather event over a selected geographical area, each observation containing values for the parameters;
performing a Principal Component Analysis (PCA) to identify and select a reduced set of principal components corresponding to a second set of parameters, the reduced set of principal components being uncorrelated, the second set of parameters being a subset of the first set of parameters, the parameters in the second set of parameters contributing at least a majority of the variance of the first set of parameters;
rotating the reduced set of principal components to provide a third set of parameters, wherein each parameter corresponds to a physical data measurement;
and
performing a logistic regression on the third set of parameters to determine the predictive equation for forecasting of the selected weather event.

3 more elements

A system for forecasting the probability of occurrence of a selected weather event, the system comprising:

selecting a geographical area, the geographical area being divided into a regular grid;
developing predictors for observed values of atmospheric phenomena within the geographical area;
collecting a plurality of observations of the predictors for each portion of the grid over a period of time;
forming a data matrix [X]having n rows and m columns, each row representing the i-th observation and each column representing the j-th parameter, where i is an index from 1 to n and j is an index from 1 to m;
normalizing the data within the data matrix to provide a scaled data matrix [Z], wherein parameters having different magnitudes of variance may be equally weighted;
calculating a correlation matrix [R] from the scaled data matrix [Z];
calculating an eigenvector matrix [E] containing eigenvectors calculated from the correlation matrix [R] and an eigenvalue matrix [Λ] containing eigenvalues calculated from the respective eigenvectors, wherein the eigenvector matrix [E] provides a set of orthogonal vectors relating to variance;
calculating a PC loadings matrix [A] from the eigenvector matrix [E] and the eigenvalue matrix [Λ];
calculating the PC score matrix [F] from the scaled data matrix [Z] and the PC loadings matrix [A];
and,
performing a logistic regression using the PC score matrix [F] to provide a probability for the occurrence of the selected weather-related event.

8 more elements

A computer program product for forecasting the occurrence of a weather event, the computer program product embodied on one or more computer-readable media and comprising:

computer-readable program code means for input of a data set comprised of observations of data parameters made during a known time period at geographical sites;
computer-readable program code means for performing a Principal Component Analysis (PCA) to identify and select a reduced set of principal components corresponding to a subset of the data parameters, the reduced set of principal components being uncorrelated, the parameters in the subset of parameters contributing at least a majority of the variance of all the parameters;
computer-readable program code means for performing a logistic regression to determine the predictive equations for forecasting the occurrence of the selected weather event.

Dependencies are inferred from the claim text.

Weather prediction method for forecasting selected events

Life of this patent

Weather prediction method for forecasting selected events

Life of this patent

Abstract

Claims16