Paper 3 



-1C anomaly water. Anomalies of -1C showed also south of the 

 Aleutians and off the coast of Oregon. A strong surface pressure 

 gradient north of 40n caused stronger than normal westerly winds 

 which contributed to the below normal heating in this area. 



There were large areas of up to -2C anomaly water centered at 

 ION/ 100W and at ICN^ lAGW. In both areasr above normal 

 northeast trade winds and cloud cover persisted most of the 

 months leading to more vertical mixing and less heating than 

 usual for April. There were much smaller areas of up to +3C 

 anomaly water west of Guayaquil to 90vi . 



Along the equator east of ^20'^lf upwelling was diminished ana the 

 surface was warmed by solar heating in very light wind 

 conditions. South of 10S along the coast of Peru^ upwelling in 

 the Peru Current maintained below normal SST's during the month. 



Maif - Sea surface temperatures increased at a below normal rate 

 over the entire ENP this month. Greatest warming/^ up to 1.7C/ 

 occurred off the coasts of Washington and Oregon out to 4C0 miles 

 offshore. The SST anomaly pattern was similar to that of the 

 previous month/^ but the area oi warm anomaly decreased somewhat 

 and the area of >-2C cold anomaly increased significantly. 



There was a strong surface high pressure cell centered near 

 35N/ 145W ana a deeper than normal Aleutian lowr causing strong 

 winds* the northwesterly winds west of the low contributed to 

 lowering the SST's southeast of the Alaskan Peninsula/ while 

 southerly winds east of the low warmed the surface off the 

 Pacific Northwest. 



Extensive warming occurred along the equator east of 115lv. 

 Positive SST anomalies were >+2C in four areas where upwelling 

 was weaker than normal. The warm offshore water moved closer to 

 the coast of Peru from the eqjator to 1CS than in any month since 

 December 1972 when El Nino reacheo its maximum intensity. The 

 normal surface high pressure center off the coast of Chile and 

 Peru was weakened this month by the passage of frequent storms. 



In the fishing grounos north of the equator/ SST's increased 

 faster than normal. In the area east of IIOW/ the large negative 

 anomalies of March decreased to near normal this month. 



June - Sea surface temperatures increased by up to 4.4C over the 

 entire ENP due to seasonal warming. The areas of >-1 C anomaly 

 decreased greatly/ and a small patch of >+1 C anomaly appeared off 

 southern California. Between 30'^ to 45N and 140W to 170W/ 

 temperatures that were up to 1.7C below normal last month 

 increased to above normal values due to decreased clouo cover 

 (increased solar radiation) and lighter winds (decreased latent 

 and sensible heat flow from ocean to atmosphere). Cold anomalies 



38 



