Aspring tide is that occurrence where the high tides are usuallyhigher than normal while the low tides are lower than expected. Thephenomenon occurs during the full and new moon and it is causedmainly by the action of the sun and the moon on the waters of theearth. During spring tide, the moon is always either between the sunand the earth or the earth in between the sun and the moon. In bothscenarios, there is usually a greater gravitational pull by the moonand the sun hence the behavior of the tides as indicated by NationalOcean Service (2016).On the other hand, neap tides occur when the moon and the sun are atright angles to each other with reference to the earth, hencecreating opposing forces. Neap tides occur during the period ofquarter moons and the water levels are usually moderate due to theopposition. Both the spring and the neap tides occur twice in a lunarmonth. The spring tides occur during the new and full moon while theneap tide occurs during the two quarter moons.
Fromthe chart for Miami, one can note that there are three spring andneap tides. The spring tides occur between October 15thto 20th,October 25thto November 4th,and November 14thto 19th.The neap tides occur between October 20thto 25th,November 4thto 5th,and from November 19th.The spring tides can be seen as the periods when the high tides arehigher than expected and the low tides are lower than expected. Theneap tides are presented in the chat as the periods when the high andlow tides are of moderate heights.
Thetidal range is defined as the variance between the high tide and thelow tide. The difference is measured in terms of the height of thetwo tides. From the graph showing the tidal ranges of Miami, it iseasy to note that the spring tides lack consistency in their heights.These effects are caused by the states of apogee and perigee. Duringapogee, the distance between the moon and the earth is great leadingto a low gravitational pull on the earth therefore, the spring tidesbecome lower. On the other hand, perigee is experienced when the moonis closest to the earth and creates a greater gravitational pull onthe earth, leading to the development of higher spring tides.
Thereis a disparity between the water levels in Milwaukee and Miami. Thewaves in Milwaukee have short wavelengths and the tidal range isgenerally lower than that of Miami. The shorter wavelengths areattributed to the effect of the weather on the lake especially wherethe wind leads to speedy waves of lesser heights. The differencesbetween the tidal ranges of the two locations are mainly attributedto the effect of the gravitational pull of the moon and the sun. Thegravitational pull has a greater effect on the ocean water than thelake water, therefore, leading to higher tidal ranges than the onesexperienced in the lake. The water levels are mainly influenced byfactors such as the wind, temperature changes, and the amount ofrainfall, which affect the amount of water, atmospheric pressure,salinity, and the water currents.
NationalOcean Service (2016). Whatare spring and neap tides? Oceanservice.noaa.gov.Retrieved 18 December 2016, fromhttp://oceanservice.noaa.gov/facts/springtide.html