1. HYDROGRAPHY OF THE NAVO CENCAL REGION FOR DEC01
                       
LT Kitch Kennedy
OC3570

2. What is hydrography Historically, the term hydrography has meant the
scientific study of the physical conditions of systems
of water. Within the field of physical oceanography,
hydrography is the branch of our field which looks
to understand the movements of the ocean through
its measurable physical properties, including:
temperature, salinity, and oxygen, and chemical
constituents.

3. Project Domain

4. Dynamic Topography
General circulation through the entire layer of the CCS.
California Current (CC)
California Undercurrent (CUC)
Davidson Current (CC)
Dynamic through driving flow.
Contour dyn-m

5. Dynamic Topography Surface signature Meandering CC
Weak Davidson current present.
Strong onshore flow into Monterey Bay
Contour dyn-m

6. Dynamic Topography Heart of the CUC CC weakening
Product of large scale gradients
Relatively strong poleward flow
CC weakening
Max depth ~500m
Contour – dyn-m

7. Dynamic Topography Both CC and CUC still apparent
Breakdown of dynamic trough
Overall weakening currents
Topography influencing CUC
Contour – dyn-m

8. Pressure fields on Sigma level
Pressure btwn dbar
Dome of low pressure corresponds to dynamic trough
CC and DC
Contour – 4 dbar

9. Pressure fields on Sigma level
Pressure btwn dbar
Stronger gradients = stronger currents
CUC influencing poleward flow along the coast
Onshore flow building pressure max in Monterey Bay
Contour – 5 dbar

10. Pressure fields on Sigma level
Pressure dbar
More variability in the flow
Core of the CUC
Meander in CC not present at upper levels
Contour – 5 dbar

11. Density vs. Salinity Curve
Equatorial Pacific
water
Pacific Sub-artic Water
-26.7
-26.2
-25.8

12. Surface Salinity
Weak salinity gradient in the heart of the data region
Fresh water signatures
Mouth of San Francisco bay
Pacific Sub-artic water
Larger salinity gradient correlates well with 0/200 dynamic height contours

13. Salinity Analysis Fresh water run-off near SF Bay not evident
Salinity max near coast
Equatorial water advected north by DC and CUC
Mixing of Sub-artic and Equatorial waters
Strong gradient may represent the boundary of the CC
Equatorial Pacific
water
Pacific Sub-artic Water
-26.7
-26.2
-25.8
Contour – 0.03

14. Salinity Analysis CUC advection high salinity along the coast
Relatively fresh pool created by subduction of surrounding waters
CTD cast plots
Equatorial Pacific
water
Pacific Sub-artic Water
-26.7
-26.2
-25.8
Contour – 0.02

15. Salinity Analysis Distinct boundary btwn water masses
Stronger currents allowing less mixing
Equatorial Pacific
water
Pacific Sub-artic Water
-26.7
-26.2
-25.8
Contour – 0.01

16. Sea Surface Temperature
Poor indicator of current dynamics
Warm water in region of dynamic trough
Highly influenced by air-sea interactions
Cooler water in vicinity of Monterey and San Francisco Bays
Cold water intrusion from SW
Contour – 0.2 degC

17. ADCP Data Qualitative comparison
Strong correlation with 0/200 and 25.8 Sigma-lvl pressure contours

18. QUESTIONS?