EGD or Upper Endoscopy Procedure. The device used during an EGD procedure is called a flexible endoscope. It is tubular in shape and is very similar to the colonoscope that gastroenterologists use to examine a patientâs colon during a colonoscopy procedure, just thinner in diameter.
What causes ocean currents? Ocean currents result from two processes - the action of wind on the surface of the water, and from variation in water temperature that causes movement- a process known as convection. Convection occurs because the oceanic waters heat up becoming less dense.
In this way, the ocean currents help regulate Earth's climate by facilitating the transfer of heat from warm tropical areas to colder areas near the poles. The water of the ocean surface moves in a regular pattern called surface ocean currents. On this map, warm currents are shown in red and cold currents are shown in blue. Image Credit: Windows to the Universe. The global wind patterns cause the surface currents to form in the uppers layer of the ocean. Where these winds blow in the same direction for long periods of time, large currents develop and transport vast amounts of water over long distances.