1. An OGCM with Movable Land- Sea Boundaries w/Application to Cook Inlet L. Oey, T. Ezer & M. Johnson Princeton Univ. & Univ. Alaska

2. Goal: A Wetting & Drying (WAD) scheme that works w/OGCM’s such as the Princeton Ocean Model (POM) p.2

3. p.3

4. p.4

5. Method: Solve Full 3-D PE (include everything), and impose conditions – 1.WETMASK= 0 for D  Hdry, = 1 otherwise. 2.if (Di,j+Di-1,j)/2  Hdry 3. if WETMASKij* WETMASKi-1,j = 0 p.5

6. One-Dimensional WAD Dynamics (1a) (1b) Condition for friction to dominate is: Then LHS of (1b) can be dropped, and (1a) & (1b) give: Typical values: r  10 -4 ~10 -3 m/s (in POM, and also Balzano, 1998),   10 -4 s -1 (e.g. M 2 tide), D = O(1) m, = O(1) m s -1, and l  100’s km for tides. (2) (3) “Advection Velocity” “Diffusivity” “Sink” if Convex “Source if Concave Note the possibility of a “breaking-wave” solution The diffusive penetration distance, Lpd say, at a given time t is proportional to D(g/r)1/2. p.6

7. A Challenging (Giant) Water-Fall Problem: p.7

8. p.8

9. Tsunami: Energy Considerations: therefore, Since At land-fall, p.9

10. Cook Inlet Alaska p.10

11. Large Tidal Range Inland  Weak Tides Offshore  p.11

12. Model of Cook Inlet, Alaska p.12

13. Flood Begins @ Upper Inlet Forcing: 12-hr tide Rivers Wind: Anchorage Nikiski Drift Riv. Augustine Is. p.13

14. Wetting & Drying: p.14

15. Low Tide, River = 0 (i.e. ~ winter) Anchorage Skiing Portage Galcier 1 st Picture Turnagain Arm Knik Arm p.15

16. p.16

17. Salinity sections in upper CI at low & high tide A B C A B C p.17

18. Salinity & rip tides in central CI I=140 I=180 Kalifornsky Beach 1 hr before high tide p.18

19. Vertical Velocity W-Contours Effects of River-Induced Buoyancy on rip tides  w/River Discharge  No River: Climatology only  Homogeneous Water p.19

20. Conclusions An OGCM with dynamic (movable) land-sea boundaries has been developed The model conserves mass & energy and has been tested for idealized and analytical solutions as well as realistic conditions in the Cook Inlet wherein forcing such as tides, winds, rivers were specified Oey, 2005: A WAD Scheme for POM. Ocean Modelling, 9, 133-150. Oey, 2006: An OGCM w/Movable Land-Sea Boundaries, Ocean Modelling, in press Financial supports from MMS, and computing supports from GFDL are gratefully acknowledged. p.20