Hydroclimatic and Circulation Anomalies Associated with the Gulf of Mexico Hypoxic Zone

• Main Author: Vines, Natalie Amanda
• Other Authors: Robert Rohli
• Format: Others
• Language: en
• Published: LSU 2005
• Subjects: Geography & Anthropology
• Online Access: http://etd.lsu.edu/docs/available/etd-04152005-083208/

The Gulf of Mexico Hypoxic Zone (GMHZ) has been observed along the Louisiana continental shelf west of the mouth of the Mississippi River since 1985. Previous research associated the surface area of the GMHZ with runoff in the Mississippi-Missouri River Basin (MMRB), with "wet" years linked to larger GMHZs than "dry" years. This research uses monthly climate divisional Palmer Drought Severity Index (PDSI) data and Palmer Hydrological Drought Index (PHDI) data and monthly atmospheric teleconnection indices are used to predict the GMHZ extent up to several months in advance, using stepwise multiple regression techniques. The predictive equations are then used to reconstruct the extent of the GMHZ for years prior to 1985. To generate a hydroclimatologic regionalization of the MMRB, a principal components analysis (PCA) is performed to identify regions of homogeneous hydroclimatic variability that may contribute to variability in GMHZ extent. Results may be helpful to environmental planners who might use the predictions in defining upcoming seasons for the commercial seafood industry, and to environmental historians who may use the hindcasted estimates to explain variation in seafood harvests.