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<br /> TABLE 1 --DAILY TIDE PREDICTIONS
<br /> tEXPLANATION OF TABLE
<br /> This table contains the predicted times and heights of the high and low wate 5 for eac," day of the year
<br /> at a number of places which are designated as reference s, ilion3 By using tidal differences from table 2,
<br /> one can calculate the approximate times and heights of the tide at many oth-r places 5v i C h are called
<br />' subordinate stations Instructions on the use of the tidal differences are found in the explanation at table 2
<br /> High water is the maximum height reached by each ric-ig tide, and low water is the minima,) height
<br /> 'reached by each falling tide Nigh and low waters can be selected from the predictions by the comparison cf
<br />' ,consecutive heights Because of diurnal inequality at certain places, however, there may be a differer%cc of
<br /> only a few tenths of a foot between one high water and low water of a day , but a marke_' d-ffert,nc,e in
<br /> height between the other high water and low water It is ,�ssentlal, therefore, in using t'le true tables to note
<br />' xcarefuify the heights as well as the times of the tides
<br /> Time —The kind of time used for the predictions at eacti reference station is rnmcated Dy the tune
<br /> meridian at the bo,mrn of each oage Day4fgnt saving tima is not used in this publicaticn I davlight sav,nq
<br /> time is required, add one (1) hour to the predicted time
<br /> Datum —The da !m from which the predicted heights are recorded is the sarne as I gal use d for the
<br /> charts of the locality The datum for the Pacific coast or the United States (including Hawa�i ansa Alaslra) t,-
<br /> the
<br /> <the mean of the lower of the two low waters of each day mor foreign coasts a datura approx,rn,3ting to mean
<br /> low water springs, Indian spring low water, or the lowest poss,ble low water is yenera ly used Thi
<br /> depression of it u datum below mean sea level (MSL) for each of she rererence stations of this volume is
<br /> given on the preceding page
<br />' Depth of water —The nautical charts published by the United States and oti ter mawi, rations show
<br /> the depth of the water as referred to a low Neater datum correspond ng to that ,your ethich It,�c pri�dir•ted tidal
<br /> ,heights are recorded ro find the actual depth of water at any time the he'aht of tha uad would be added to
<br /> ,the charted depth if the height of tide is negative—that is, if there ,s a -rtir,us . ,-, (—) ct.iore Pie tahular
<br /> height—the height snould be subtracted form the charted depth For any tirre betwean hie h ai,d lova water
<br /> the height of the tic!e may be estimated from the he,ghts o= the prucedinr aria nufcilo,rig,; t des or table 3
<br /> Imay be used The reference stations in table 1 contain the heights in centirneters as well as .n Leet
<br /> Variation in sea level —Changes in winds and barometric conditions cause vanat ons n :2a levul
<br /> from day to day In gen,:,uI, with onshore winds or a I m barometer the he ghts of both the high and low
<br /> waters will be higher than predicted while with offshore winds or a high ba,ometer they 4r ' -'a love There
<br /> are also seasonal variations in sea level but these variations have been included in the prey cnons for each
<br /> station At ocean stations the seasonal variation in sea level to uSu211y less than half a foo,
<br /> I At stations on tidal rivers the average seasonal variation in river level alle to ftes'ie s ar, t
<br /> may be considerably more than a foot The predictions for these stations nclude an a lot ante fur t,it,
<br /> seasonal variation representing average freshet and drought cond Mons Unusual ire_�ne's or
<br /> however will cause the tides to be higher or lower, respectively, th? i ureoicted
<br /> dumber of tides --There are usually two high and two low watc in a day Tine, , �c'v the P1ccn
<br /> more closely than they do the Sun and the lunar or tidal day is about 50 mire res lor;r - t^,- 'ire so,Gr qday
<br /> This causes the tide to occur later each day, and a tide that has occu re❑ near the en ' 2, e calendar day
<br /> will be followed by a corresponding tide that may slop the next day ard occur in the e,r ymorr,Fny of ho
<br /> third day Thus on certain days of each month only a single high c a singe lots. va'r ,ccurs At some
<br /> Stations during portions of each month the tide becomes diurnal—that i,,, o ily ore ri,gh and one lov, water
<br /> will occur during thp period of a lunar day
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