|
|
|
|
|
|||||||
| Strong low-level cold outflow
from the interior of Alaska extends through Prince William Sound, extending
from Valdez Arm south through Montague Strait. |
| Under support from the Oil Spill Recovery Institute
(OSRI), the AEFF operates a real-time version of the Regional Atmospheric
Modeling System (RAMS), producing 36 hour forecasts for the greater Prince
William Sound (PWS) initialized at 12 UTC (12Z). This is done using a nested-grid
approach (64, 16, and 4 km grid mesh), with output every hour. Forecast graphics for Grid 2 (Southern Alaska and the Gulf of Alaska), Grid 3 (greater PWS region) and sub-domains (PWS and Cook Inlet) can be found on the AEFF Weather Briefer's Page. Examples of the areas covered by the plots are shown below, and as well, instructions on how to access the animated times series of plots from the Weather Briefer's Page. |
| The plot domains
available from the Weather Briefer's Page (Click on the images for the full-sized plots) |
|
|
|
| Grid
2. With a 16-km grid spacing, Grid
2 covers Southern Alaska and most of the Gulf of Alaska. This grid is a "go-between"
between Grids 1 and 3, transferring the synoptic scale forcing to the finest-mesh
grid. |
Grid
3. The 4-km grid spacing of Grid
3 allows for The large-scale forcing to interact with the extreme topography
of the PWS surroundings to provide very localized circulation and precipitation
patterns . |
|
|
| PWS
Subdomain. This subdomain of
Grid 3 shows greater detail of the PWS proper. Note the jet exiting
Port Wells. |
Cook
Inlet Subdomain. The Cook Inlet
subdomain of Grid 3 shows greater detail of that area. Note the difference
in wind regimes between Cook Inlet and PWS, seperated by just a few 10s of
km. |
| First, go to the lower-left frame on the page
and scroll down to the section of the page shown to the right. Then,
click on the RAMS button. |
|
| Now, go to the upper right-hand panel of the
frame and find this frame: |
|
|
|
Select the "12Z cycle" as shown. From the pull down menu shown above, chose a grid domain. (Note that the "RAMS Grid 3 Shelikof" domain is not available for this cycle.) |
|
| Next, select a graphical product from the menu
shown on the right, You can also choose a time seperation between displayed
images. Note that "hourly" means 3 times as many frames and this can
result in very long download times for slow network connections. Finally, press the "LOAD!" button to load the images. |
|
|
After the images have loaded (this can take a few seconds to several minutes, depending on network speed and number of inages), the page is ready to animate. Go to the lower right-hand frame and find the menu shown in the figure above. Click "Start" to begin a time-series loop of the plots. The time spacing can be determined from the "speed" pull-down menu. smaller times (150 ms) give faster animations, larger times (1 sec) give slower animations. The "||<" and ">||" buttons step backward and forward one time respectively. |
