Linear explorations with merged CCMP/ASCAT winds (1987-2013)...

Related pages:

- Solomon Sea glider main page
- Later glider page
- Aviso comparison page
- Argo comparison page
- SW Pacific main page
- ERS winds page

Note: Monthly-mean winds were constructed from original daily files.

CCMP winds were available from July 1987 to June 2011, ASCAT winds from April 2009 to December 2013. For the overlap period, a simple average was made.

"Interannual" means the average annual cycle was removed, and the residual smoothed with a 7-month triangle filter.

- Mean solution (from Qiu et al 2010)
- Wind mean vectors and variance ellipses in frequency bands (Solomon Sea region)
- Monthly (Overlay central section for Ekman transport below)
- Annual cycle
- Interannual
- Annual cycle from ASCAT only (2009-13, finer spatial resolution):
- Variance ellipses
- Magnitudes: Mean stress Variance ellipse major axis
- Mean magnitude minus variance ellipse major axis (Do winds reverse?)
- Direction (Pos. East, counterclockwise): Mean stress Variance ellipse major axis

- Winds along sections
- Along 154°E
- Interannual along 10°S, inside the Solomon Sea
- Winds along 10°S basin-wide (RW model forcing): Taux Curl

- Basin winds
- Variance ellipses: Monthly Annual cycle Interannual
- Curl RMS: Monthly Annual cycle Interannual
- Decadal changes: 1987-2013 mean Curl Tau difference 99-13 minus 87-96 Curl difference
- Low-frequency Curl(x,t) averaged in latitude bins
- Nino/Nina winds and curl "composites" for various periods:

1987-2014 1987-99 2000-14 2007-14 (glider period)

- Ekman transport calculations

Based on a diagonal section down the center of the Sea- Interannual winds rotated to Along - and Cross-Sea components

Compare section east of Solomons: Parallel eastern section Difference (circumisland wind) - Time series integrated along the section (Sv) (Glider period) (Demeaned)
- Time series on latitude (Glider period)
- Implied dh/dt at S.I. coast (Glider period)
- Ekman slides sent to Russ (7 Feb 2014) (pdf)
- (Aug 2015) Annual cycle winds and Ekman transport
- Annual cycle Z20 and Ekman inference
- Interannual alongsea windstress and glider transport

- Interannual winds rotated to Along - and Cross-Sea components
- Rossby solution
**(Early work, Feb 2014**. See next section)

CCMP/ASCAT interannual winds.

Unless noted: c=3.0m/s, Damping=24 months.- h: thermocline depth anomalies, positive down
- ug on 165°E: All Glider period y=spz3

Total u_rw arriving at the Solomon Islands - RMS ug at the western boundary input to the NGCU: Incoming transport RMS(y) Integral RMS
- Rossby/Godfrey solution for Solomon Sea transport (Preliminary)
- Solution broken into WBC, direct, Sol.Is.: Compare glider transport Compare SOI (2 choices of dividing latitude) 1987-2013

Compare 700m obs - Compare SI, Direct, WBC pieces separately (700m): c=3.0m/s c=2.5m/s 1987-2013
- (Glider transport interannual and SOI)
- Annual cycle solution:
- Urw: At 165°E 6°S (Further S is very weak)
- Rossby solution (in parts) and observed Sol.Sea transport

- Later Rossby/TDIR work
**(Nov-Dec 2014)**

Same 1987-2013 CCMP-ASCAT winds. Updated/improved glider transports, further sophistication.- One experiment rotating the winds to along-Sea: Show region EOFs of interannual along-Sea winds
- Wind documentation (sequences of maps):
- Misc: Nino indices overlaid
- Classes of Rossby-TDIR solutions:
- Effect of damping term (fraction of wind forcing left after damping): 24-month damping 48-month
- WBC/Direct/Sol Is (4-way) split, no circumisland term:

V2: uses Rossby ug input only for SI: c=2.5m/s c=3.0m/s c=3.2m/s c=3.5m/s - WBC (Incl 12°S in WBC, no "direct")/Sol Is (3-way) split:

V3b: c=2.5m/s c=3.0m/s c=3.5m/s (Note circum labels are wrong: no circumisland term here) - WBC (Incl 12°S in WBC, no "direct")/Circum-island corrected/Sol Is (3-way) split:

V4: Includes both ug,vg Rossby transport inputs: c=2.5m/s c=3.0m/s c=3.5m/s - V5 (Use RD transports (24-month damping unless noted):
- Speed c: 2.5m/s 3.0m/s 3.5m/s
- Compare damping strength: 24, 48 month, or no damping on one page

- V6 (sixcharmi transports):

2.5 m/s 3.0m/s 3.5m/s D = 24mon: X X X D = 48mon: X X X D = None: X X X - Compare observed and TDIR-predicted transport for various southern BC latitudes:

7 latitudes (separate plots) Test: zonal inflow only to S.I. - As V4 but experiment with different coastal averaging for circumisland term (above are 1° from coasts):

All for c=3.0m/s: Coastal gridpoint only 2° from coasts (Slight differences) - Damping/speed solution envelopes: 9 solutions Overlay Nino3.4 Low-frequency
- As V4 but for
**Average Annual Cycle**, c=3.0m/s

Add real time to 153042, all curves in 1 panel (sixcharmi only)

For obs through 153042, include Vrw at Sol Sea mouth, WBC from 24.5°S

- Rossby Sol Sea inflow and Nino3.4
- Rossby Sol Sea inflow elements and corresponding observations
- Circum-island wind term: Interannual, both sides Annual and interannual differences
- Rossby-implied WBCs:
- Coast of Australia (simple Rossby mass balance with zero BC at 29°S):
- WBC interannual anomalies Combined u_rw and WBC
- RMS transport: Incoming transport WBC

No-damping comparisons: Incoming WBC - Correlation of Australia coast WBC with glider transport

- WBC on the east coast of Solomons (TDIR):
- WBC interannual anomalies
- Details: Show N,Sbound split (y,t) Incoming and split transport totals Overlay Nino3.4

Checking using full cross/alongshore terms - Damping comparison:
- Incoming and split totals: 48-month damping No damping
- S,Nbound split (y,t): 48-month No damping

- Extend back to 1990: Incoming and split transport Overlay Nino3.4 WBC(y,t)

Low-frequency: 25-month running mean Overlay Nino3.4 4-year running RMS

- WBC on outer coasts of both Australia and the Solomon Islands (TDIR):
- Early run to 2013: WBC 1990-2013, include Nino3.4
- Damping comparisons: 48-month damping No damping
- Incoming URW: 1990-2014 2007-14
- WBC 2007-2014 (FC)
- What if the WBC integration started at latitude y?
- Time series overlaid: 12.5-22.5°S by 2° 12.5-17.5°S by 1° 14.5-17.5°S by 1° (most relevant)
- Correlation (of WBC with itself starting at 28.5°S, I think)

Correlation of TDIR solution with obs for different starting lats - Solutions for latitude/c/damping choices compared to observations

Add 3 realtime missions through 153042 - Solutions for y_s=15.5°S (overall best):

c=3.0m/s, D=24 c=3.5m/s, D=24 c=3.0m/s, D=48 c=3.5m/s, D=99 - Update for realtime through 153042. Also include Vrw contribution at Sol Sea mouth:

- Distance traveled by a Rossby wave in 1 year
- TDIR Solomon Sea inflow back to 1987
- Time series for different southern BC choices (FC):

28.5°S 24.5°S 20.5°S 18.5°S 15.5°S - Wind/curl era-mean maps:

1988-2014 1988-1996 1999-2014 Difference - Another way to look at it:

Time-dependent IR soln: Au-S.A. / NZ-S.A. / S.I.-S.A. / Au-S.I. /tdir AU-NZ

- Time series for different southern BC choices (FC):

- Coast of Australia (simple Rossby mass balance with zero BC at 29°S):
- Mean currents from these winds (Island Rule):
- Island Rule calculation details (circumisland term):
- Winds observations if gridded ... Original (1/4°) On 1° grid
- Relevant regions: Block colors Lines over mean curl
- Circum-island wind terms: NZ Australia Solomon Islands

- Mean WBC along the east coast of the Solomons (Result for 2007-13 winds)
- Results (Transport relative to S. America (Sv)):

Region Circum-Is. term Curl term Total Direction NZ –0.18 22.43 22.25 Northward Solomons –0.86 –9.61 –10.47 Southward Australia 0.50 13.79 14.29 Northward Au if no NZ 0.50 11.78 12.28 Northward

Notes:

14.29 – 22.25 = –7.96 (southward) between NZ and Australia

14.29 – (–10.47) = 24.76 (northward) between Solomons and Australia

ITF = 14.29 Sv

Interior transport inside Solomon Sea ~ –2Sv (southward)

- Island Rule calculation details (circumisland term):

- One experiment rotating the winds to along-Sea: Show region EOFs of interannual along-Sea winds
- Figures from Qingdao and UW talks (Oct and Dec 2015)
- OFES comparisons: Full-depth OFES OFES to 700m
- Obs transport and TDIR solution: Interannual Annual cycle (pdfs)
- Winds and curl in late 2013