Synoptic Map-Pattern Classification Using Recursive Partitioning and Principal Component Analysis
Open Access
- 1 May 2002
- journal article
- Published by American Meteorological Society in Monthly Weather Review
- Vol. 130 (5), 1187-1206
- https://doi.org/10.1175/1520-0493(2002)130<1187:smpcur>2.0.co;2
Abstract
A method for classifying synoptic-scale maps into discrete groups is introduced. Tree-based recursive partitioning models are used to develop mappings between synoptic-scale circulation fields and the leading linear and nonlinear principal components (PCs) of weather elements observed at a surface station. Statistically unique but climatically insignificant patterns are avoided by identifying map patterns based on their association with indices related to local weather conditions. The method requires few user-adjustable parameters and includes an algorithm that provides objective guidance for determining the appropriate number of map patterns to retain. The classification method is demonstrated using daily sea level pressure and 500-hPa geopotential height maps from a domain covering British Columbia and the northeastern Pacific Ocean. The linear and nonlinear weather element PCs are derived from daily measurements of surface temperature, dewpoint temperature, cloud opacity, and u and υ wind components taken at Vancouver, British Columbia. Classification performance is tested by applying the method to precipitation and air quality scenarios. Results are compared with those from unsupervised map-pattern classifications based on the k-means clustering algorithm. Results from recursive partitioning models using linear weather element PCs as targets were better than those from the k-means algorithm. Recursive partitioning trees using nonlinear PCs as targets performed slightly worse than those using linear PCs as targets. Interestingly, trees using gridpoint circulation data as inputs outperformed models that used truncated PCs of the circulation data as inputs. Poorer results were found not to result from loss of information due to truncation of the PCs. Instead, the way information is encoded in principal component analysis (PCA) may be responsible for the poor classification performance in the recursive partitioning models using circulation PCs as inputs.Keywords
This publication has 36 references indexed in Scilit:
- The preferred structure of variability of the northern hemisphere atmospheric circulationGeophysical Research Letters, 2001
- Using Self-Organizing Maps to Investigate Extreme Climate Events: An Application to Wintertime Precipitation in the BalkansJournal of Climate, 2000
- A regime view of northern hemisphere atmospheric variability and change under global warmingGeophysical Research Letters, 2000
- Application of Non-hierarchically Clustered Circulation Components to Surface Weather Conditions: Lake Superior Basin Winter TemperaturesTheoretical and Applied Climatology, 1999
- Relationships between Synoptic Climatology and Atmospheric Pollution at 4 US CitiesTheoretical and Applied Climatology, 1999
- A NEW SPATIAL SYNOPTIC CLASSIFICATION: APPLICATION TO AIR-MASS ANALYSISInternational Journal of Climatology, 1996
- Advanced supervised learning in multi-layer perceptrons — From backpropagation to adaptive learning algorithmsComputer Standards & Interfaces, 1994
- Synoptic Circulation and Summertime Ground-Level Ozone Concentrations at Vancouver, British ColumbiaJournal of Applied Meteorology and Climatology, 1994
- A stochastic approach for assessing the effect of changes in synoptic circulation patterns on gauge precipitationWater Resources Research, 1993
- Objective Specification of Monthly Mean Surface Temperature from Mean 700 mb Heights in WinterMonthly Weather Review, 1983