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EFFECTS OF OCEAN CUEEENTS ON CLIMATE. 

 By Mr. Jambb Rankin, M.P. 



i 



I WISH, this evening, in the very few remarks which I have to make, to put 

 before you one leading idea, so that you may be able to carry away and remember 

 the object and aim of this short paper ; and the idea or point which I wish to im- 

 press upon you is this— That ocean currents are far more important agents in 

 distributing the sun's heat over the surface of our globe than are the currents of 

 air, or, as we call them, the winds. 



To show this, I must ask your attention for a few minutes to some of the 

 known facts connected with that most remarkable current called the Gulf Stream, 

 and I take this current as an example because it is by far the best knovim. 



I do not intend to discuss to-night the question of the dynamics of the Gulf 

 Stream, but merely to institute a comparison between it and currents of au:, with 

 a view of testing which is the more important factor in the distribution of heat, 

 and therefore the more important as an agent affecting the climate. The Gulf 

 Stream, as is so well known, issues out of the Gulf of Mexico, round the Cape of 

 Florida, as a current about 30 miles wide, 2,200 feet deep, and moving at the rate 

 of 4 miles an hour, and its temperature is about 80° Fah. 



Now it has been calculated that such a body of water carries with it 

 into the Northern Atlantic Ocean an amount of heat equal to an energy of 

 77,479,650,000,000,000,000 foot pounds daily, or in other words a quantity equal to 

 a quarter of aU the heat of the sun poured upon that area. This amount of heat 

 derived from the sun's tropical rays is equal to half the heat of the sun which falls 

 upon the entire Arctic circle, or to an amount of heat dispersed over a belt of 32 

 mUes wide on each side of the equator, or, on a surface of 1,560,935 square miles. 

 This enormous amount of heat poured into the Atlantic, has the effect of carrying 

 off the heat from the tropics, and distributing it over the temperate and polar 

 regions, and its effect upon our island country is an elevation of temperature of 

 12° above the normal temperature of our latitude. 



It must not, however, be supposed that 12° rise of temperature is the whole 

 effect of the Gulf Stream upon the climate of our island, or of north-western 

 Europe, or of the North Atlantic generally, but the 12° is only the rise above the 

 mean or normal temperature of our latitude, for other places in the same latitude 

 as we are have their temperature affected by ocean currents as well as we ; and on 

 the other side the effect of cold Polar currents has to be considered, for the heat 

 of the warm Gulf Stream is to a great extent employed in counteracting the 

 depression of temperature caused by the Polar currents. 



I will endeavour, very briefly, to show the probable fall of temperature in the 

 North Atlantic were there no Gulf Stream of hot water. 



We have seen that the amount of heat carried by the Gulf Stream equals the 

 heat of the tropical sun on a surface of 1,560,935 square miles, and as the amount 



