5-1 I ncaior Map for 5-2, 



OPBIT 04390 06SEP79 211850 TO 212050 GMT GhIN 1-+=: THRESHOLD OFF TILT ANGLE 0-0 

 GRID CENTER DhTh; 211951 GMT 55.68N 155 .82W SUN EL 39 AZ 160 ROLL -0-0 PITCH 0-0 YAW 0-4 



■19 .27 .39 -S' 



algorithms: 02 01 01 00 00 03 02 00 00 00 



963 SCAN LINES PROCESSED T SCAN LINES HISSING 



.83 1.2B 2-11 ".46 5.69 9.35 11.98 25.25 32.1 



CIP VER CRT NO DPS VER SPEC- # FRAME # 

 V ZE312341 V821015 F732040 ZG312T41 



The resulting high productivity supports the valuable fisheries of the area. 

 The patchiness illustrated here is, in general, similar to the variations in 

 benthic marine populations. 



Patterns resulting from flow of water from these areas into the westward 

 Alaska Current along the shelf break can also be identified in the image. 

 Off Kodiak Island, the flow is converging from a broader eastern 

 boundary current into the swift (speeds >1 m s~'), narrow, western 

 boundary current of the Alaskan Stream (Royer. 1981). Further 

 convergence is apparent as the flow continues to the southwest. 



Because of the high coastal runoff to the east of Kodiak Island, gray 

 tones in the image near this coast will be affected by river and glacial silt as 

 well as by phytoplankton pigment concentrations. Features of the 

 nearshore circulation are thus made visible on the image. 



The narrow Alaska Coastal Current (<20 km wide) can be seen adjacent 

 to Kayak Island as a lighter tone due to large silt loads from glaciers 

 (Malaspina Glacier and others). At the southwest tip of the island the flow 

 bifurcates. A portion joins the Alaska Current, flowing westward along 

 the shelf break, while the rest flows into a cyclonic pattern behind the 

 island (arrows. 5-1). This nearshore flow is joined by the silt-laden Copper 

 River water (white) and flows westward into Prince William Sound where 

 additional, less silty water enters to cover the Copper River water. This 

 nearshore circulation has been identified by satellite-tracked drifting 

 buoys (Royer ei ai. 1979). The nearshore water of the Alaska Coastal 

 Current leaves Prince William Sound and brings nutrient-rich water to the 

 shelf fisheries east of Kodiak Island. From the image, it can be seen that 

 part of the coastal current enters Cook Inlet through the Kennedy 

 Entrance. Within Cook Inlet, light tones are caused by the high silt 

 concentrations from the Susitna and Mastanuska Rivers. There is little 

 evidence of the Alaska Coastal Current to the west of Kodiak Island since 

 the fresh water influx is small. 



5-2. Nimbus-7. Orbit 4390. 6 September 1979. CZCS Pigment Image. (M-Middleton Is., K-Kayak Is ) 



References 



Royer, T. C, 1981: Baroclinic transport in the Gulf of .Alasl(a. Parts I and II. J. Marine 



Res. 39, 239 266. 

 Royer, I.e., D. V. Hansen, and D. .1. Pashinski, 1979: Coastal flow in the northern Gull ot 



Alaska as observed by dynamic topography and salellite-lracked drogued drifl buoys, 



J. Plus. Ocecmogr.. 9, 785-801, 

 Thomson, R, E,, 1972: On the Alaskan Stream, / Phvs. Oceanogr.. 2, 363 371. 

 Wright, C, 1981: Observations of the Alaskan Stream during 1980. NO A A Technical 



Memorandum ERL PMEL-23. 



