TIffi CARIBBEAK AREA — COSTA RICA 



nSHEPT RESOURCES 



Character of the Coasts 



Costa Rica has coastlines on both the Caribbean and Pacific. C)n the Pacific side the 

 coast is about 360 miles in length and on the Caribbean, about 181 miles. Both coasts 

 were visited by the Mission. 



Pacific Coasts — The Pacific coast of Costa Rica extends in a northeasterly direction 

 from Burica Point (the boundary with the Republic of Panama) to Salinas Bay, which it shares 

 ■with the Republic of Nicaragua. In this stretch of coastline there are a nxmber of large 

 bays. Among these, from east to west, is the Gulf of D\ilce, the Gvlf of Nicoya, the Gulf of 

 Culebra, Elena Bay and Salinas Bay. In addition, there are several smaller bays, such as 

 Golfito, Ballena, Potrero, Culebra, Potrero Grande, and Juanilla. The only population center 

 of any consequence on the coast is Puntarenas situated on the east side of the Gulf of Nicoya 

 and connected with San Jose and the interior plateau by rail. 



The physical nature of the coastline is more or less typical of the Central American 

 Coast. That part of the coast open to the sea is usually sandy beach, sometiTies backed by 

 low, swampy, mangrove areas and sometimes by high, rocky cliffs. Numerous small, rocky 

 islands and ledges occur along the coast and in the bays. Further offshore the bottom may 

 be sand or mud mixed with shells. The presence of offshore banks has been reported from 

 time to time but definite information is still lacking. The 100-fathom curve is found at 

 distances from J to 30 miles offshore. TTithin the 100-fathom curve, especially in the Gulf 

 of Dulce, deep holes are found. Thus 110 fathoms is found at the head of the Gulf of Dulce 

 while near the mouth only 10 fathoms is reported. For the most part, however, the depths 

 shelve off gradually to 100 fathoms and then abruptly to 200-1000 fathoms. 



Few rivers of any size empty on the Pacific side. The largest are the Rio Tempisque, 

 Rio Viego, Rio Goto, and Rio Ksquinaa. The spring tides rise 10.8 feet and neaptides, 8.5 

 feet at Puntarenas, 



Thei^ are two seasons, the rainy and the dry, the former generally lasting from April to 

 Novenber, During the rainy season, the winds blow from the south-southwest and in September 

 and October often reach gale force, accon^janied by heavy rain. During the dry season calms 

 prevail, but in the evening there are often violent "chubascos" which blow from a direction 

 between north and east and are accompanied by heavy rain; these stonns seldom last longer 

 th^n 3/4 hour, 



Oceanographic conditions along the coast of Central America are not well knownj but in 

 some localities, such as the Gulf of Panama and the Gulf of California, upwelling followed 

 by great production of phytoplankton takes place in certain seasons of the year. It is not 

 definitely known that similar conditions occur in other regions in this general areaj but 

 the indications of swift currents, numerous eddies, and rapidly changirlg conditions would 

 be conducive to thorough mixing and local vertical movements. Tliese should be expected to 

 enhance the productivity of the waters. A further indication of mixing is provided by the 

 range of average surface water temperatvires. Off Costa Rica, the coolest water, 80.2 degrees 

 F., is found in November and the warmest, 82,0 degrees F., in May, 



The surface waters of the Pacific coast of Costa Rica are derived from the Equatorial 

 Counter Current. This is a sanewhat irregular current which sets to the eastward between 

 the northeast trade drift and the Equatorial Current and carries a body of warm water to the 

 coast of Central America. Though the limits of the counter current are imperfectly defined, 

 it appears to be comprised between the Equator and the parallel of 8 degrees N. — its greatest 

 width is never more than 5 degrees of latitude, and it generally keeps between latitude 5 

 degrees N. and 8 degrees N. The velocity of the current appears to be from § to 2 knots. At 

 about 8 degrees N., just outside the 100-fathom line on the Costa Rican coast, the Equatorial 

 Counter Current seans to split. One portion swings northwestward along the coast of Central 

 America, the other moves southeastward and joins a current moving southwestward from the Bay 

 of Panama, 



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