Effects of ENSO, NAO (PVO), and PDO on Monthly Extreme Temperatures and Precipitation

• Other Authors: Brolley, Justin Michael (authoraut), O'Brien, James J. (professor directing dissertation), Berg, Bernd (outside committee member), Ahlquist, Jon (committee member), Cai, Ming (committee member), Ruscher, Paul (committee member), Department of Earth, Ocean and Atmospheric Sciences (degree granting department), Florida State University (degree granting institution)
• Format: Text
• Language: English
• Published: Tallahassee, Florida: Florida State University 2007
• Subjects: Meteorology; Canada; Pacific; North Atlantic; North Atlantic oscillation
• Online Access: https://diginole.lib.fsu.edu/islandora/object/fsu%3A184995/datastream/TN/view/Effects%20of%20ENSO,%20NAO%20%28PVO%29,%20and%20PDO%20on%20Monthly%20Extreme%20Temperatures%20and%20Precipitation.jpg

The El Nino-Southern Oscillation (ENSO), the North Atlantic Oscillation (NAO), the Pacific Decadal Oscillation (PDO), and the Polar Vortex Oscillation (PVO) produce conditions favorable for monthly extreme temperatures and precipitation. These climate modes produce upper-level teleconnection patterns that favor regional droughts, floods, heat waves, and cold spells, and these extremes impact agriculture, energy, forestry, and transportation. The above sectors prefer the knowledge of the worst (and sometimes the best) case scenarios. This study examines the extreme scenarios for each phase and the combination of phases that produce the greatest monthly extremes. Data from Canada, Mexico, and the United States are gathered from the Historical Climatology Network (HCN). Monthly data are simulated by the utilization of a Monte Carlo model. This Monte Carlo method simulates monthly data by the stochastic selection of daily data with identical ENSO, PDO, and PVO (NAO) characteristics. In order to test the quality of the Monte Carlo simulation, the simulations are compared with the observations using only PDO and PVO. It has been found that temperatures and precipitation in the simulation are similar to the model. Statistics tests have favored similarities between simulations and observations in most cases. Daily data are selected in blocks of four to eight days in order to conserve temporal correlation. Because the polar vortex occurs only during the cold season, the PVO is used during January, and the NAO is used during other months. The simulated data are arranged, and the tenth and ninetieth percentiles are analyzed. The magnitudes of temperature and precipitation anomalies are the greatest in the western Canada and the southeastern United States during winter, and these anomalies are located near the Pacific North American (PNA) extrema. Western Canada has its coldest (warmest) Januaries when the PDO and PVO are low (high). The southeastern United States has its coldest Januaries with high PDO and low PVO and ...