Why is shallow water warmer

Geothermal energy emanating from the Earth averages only about one tenth of a watt per square meter. At that rate of heat flow without taking ocean currents into account , it would take well over a year just to heat the bottom meter of the ocean by one degree Centigrade.

However, the ocean is not standing still. Complex deep ocean currents driven by density variations in temperature and salinity are constantly replacing the bottom layer of ocean water with colder water.

Then what role does wind play? So we have large changes where, in the summertime, we could have temperatures in the 80s, and in the wintertime, those temperatures could be in the upper 30s to 40s. NewsWorks went to the beach to find out. When I go online and check out what the ocean temperature is in Cape May or Atlantic City, where is that information coming from, and how is it measured? Most of that information is coming from […] satellites in space, which are giving maps of temperatures.

We work with an ocean observing system that puts out maps of temperatures, and these are measured from satellites that are orbiting around the planet. So, nobody is sticking a little temperature gauge into the water? Some are. There are a few ways we can do that. One is with buoys in the ocean. NOAA, the National Oceanic and Atmospheric Administration, they run a series of buoys that are offshore that report back real-time temperatures of the surface ocean, wind conditions, meteorological parameters, all different types of things get sent back.

They patrol the waters for about 30 days at a time, measuring things like temperature, salinity of the water, and they send that information back to us every three to four hours. When I check the temperatures for some beaches near us — for example, Atlantic City and Cape May — they are about 40 miles apart, but the ocean temperatures … there can be a good six-degree difference.

So when a water body cools due to convection during a cold season it cools only until it reaches 4 Centigrade above zero. Then convection stops and the water body covers with ice.

Now surface water has a temperature of 0 Centigrade or less and bottom water has a temperature of 4 Centigrade. This works only in temperate latitudes because far to the north rivers can freeze to its bottom.

Why is surface water warmer than deep water? Seryozha R. Nov 10, Explanation: The Sun heats water. Related questions What is runoff and how is it important to surface water reservoirs?

As this happens, the thermocline breaks down. This allows mixing of the upper and lower water systems. The air temperature continues to decline with the onset of winter, and the surface layer of the lake freezes. This water is less dense than the water in deeper layers and once again a thermocline forms. With spring warming, the ice melts as the temperature rises and the thermocline is disrupted.

This allows nutrients to enter various food webs and leads to the development of algal and microorganism blooms. Ocean upwellings are fundamentally the same as those described above for lakes. Seasonal thermoclines are disrupted when the temperatures of the deeper currents approach the temperatures of the surface currents. In oceans, mixing results in massive plankton blooms in the upwelling. The movement of the current carries the upwelling to a different location.

For example, mixing on the Antarctic shelf fuels upwellings along the western coasts of both South America and Southern Africa.