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.
Surface ocean currents are driven mainly by winds and are affected by seasons.Deep ocean currents are driven mainly by density and temperature gradients. However the most important and fundamental causes for the formation of the ocean currents are solar heating,winds and gravity. 1) Ocean currents are driven by the circulation of wind above surface waters. The water moves in the direction of the wind.