A Multi-Index GEM Technique and its Application to the Southwestern Japan/East Sea
Abstract
This paper demonstrates a new gravest empirical mode (GEM) technique that constructs multi-index lookup tables of temperature and specific volume anomalies using historical hydrocasts as a function of three indices: round trip travel time from sea floor to the surface, sea surface temperature, and pressure. Moreover, the historical hydrocasts are separated into non-mixed layer (NML) and mixed layer (ML) groups, and a single GEM field is constructed for each group. This is called the MI-GEM technique. The appropriate dates for MI-GEM fields are determined by the monthly distribution of the number of NML and ML profiles in the historical hydrocasts, which are also used well correlated with the strength of the winds during the 2 yr. of observations. Comparisons with in-situ CTD casts demonstrate that the MI-GEM technique almost always produces improved full water column profiles of temperature and specific volume anomalies. Whereas the residual GEM estimates had exhibited qualitatively erroneous features like temperature inversions in the near-surface layer and too thin or thick intermediate water layers in some regions, the MI-GEM estimates avoid those problems, which were inherent to the residual GEM technique in the southwestern JES.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2005
- Accession Number
- ADA448913
Entities
People
- D. R. Watts
- Douglas A. Mitchell
- Jae-Hun Park
- Karen L. Tracey
Organizations
- United States Naval Research Laboratory