> Sorry - this message had a typo in the e-mail address.
> Here it goes again.
> Cisco.
> 
> ----------
> From: 	James Manning
> Sent: 	Thursday, May 20, 1999 7:08 AM
> To: 	'sci1@en323.gso.uri.edi'; 'real-timers@dartmouth.edu'
> Cc: 	James Manning
> Subject: 	Edwin Link updates (20 May)
> 
> 
> Hello All,
> 
>   We have been conducting a series of experiments
> to examine the sensitivity of model solutions to
> updates in the hydrographic informationas well as the 
> use of shipboard winds and heat fluxes.
> 
> Here's what we've found comparing the modeled
> and observed positions of 4 drifters (2 in the mixed
> site - along the 45m isobath and 2 in the stratified
> site- along the 60m isobath):
> 
> 1) Base Case (May17_FCAST)
> 
>     April broadscale cruise IC T and S fields, hindcast and forecast
>     winds and heat fluxes from the AVN model through 18 May.
> 
>     Mean separation between model and observed drifters: 4.65km
> 
> 2) Case 1 (May17_FCAST2)
> 
>     As in Base Case, but updating the hydrography with the T,S
>     obtained during the 11-14 May bongo survey.
> 
>    Mean separation between model and observed drifters: 3.80km
> 
> 3) Case 2 (May18_FCAST)
> 
>    As in Case 1, but updating winds and heat fluxes with latest
>    forecast/hindcast through 19 May. 
>   
>    Mean separation bewteen model and observed drifters: 3.70km
> 
> 4) Case 3 (May18_FCAST2)
> 
>    As in Case 2, but using observed (shipboard) winds and heat flux 
>    estimates.
> 
>    Mean separation between model and observed drifters: 2.56km 
> 
> All drifter comparisons above are conducted at identical points
> in time.
> 
> Comments:  the biggest improvement to the Base Case was the use
> of observed winds and heat fluxes.  During the simulation period the
> model winds were more northward (NW instead of WNW) and stronger than 
> those measured by the ship.  The observed heat fluxes were higher by 
> about 30% during peak "heating periods".  With these values we did not 
> observe any signs of the model solution developing jets/spurious flows
> near 
> the open boundaries due to the higher heat flux input.  The water column
> at the model-stations we examined (near the tidal front area/60m isobath) 
> was warmer throughout the water column - onset of stratification is
> observed 
> during peak warming but does not persist.  We are going to experiment with
> 
> a decrease in the EKMIN, EHMIN and EQMIN parameter set to see if this 
> will help "hold" the stratification.  We discussed this also with the
> Endeavor 
> team this morning during the regular 0830h radio contact and they may try 
> the same and we'll compare notes.  This is a non-trivial departure from
> the 
> FCAST parameters and hence any change of this type will be closely 
> scrutinized and watched.
> 
> We'll stop here for now.
> 
> Cheers,
> Cisco amd Jim.
> 
>