How does the jet stream and water currents influence weather

and climate?

Temperature• The jet stream is a current of fast

moving air found in the upper levels of the atmosphere. This rapid current is typically thousands of miles long, a few hundred miles wide, and only a few miles thick. Jet streams are usually found somewhere between 6-9 miles)above the earth's surface. The position of this upper-level jet stream denotes the location of the strongest SURFACE temperature contrast (as in the diagram). During the winter months, Arctic and tropical air masses create a stronger surface temperature contrast resulting in a strong jet stream. However, during the summer months, when the surface temperature variation is less dramatic, the winds of the jet are weaker.

Wind Speed and DirectionThe winds in the jet stream not only steer storms, but also help determine the locations of areas of high and low air pressure at the Earth's surface. Winds begin with differences in air pressures. Pressure that's higher at one place than another sets up a force pushing from the high toward the low pressure.The greater the difference in pressures, the stronger the force. The distance between the area of high pressure and the area of low pressure also determines how fast the moving air is accelerated.

How do ocean currents affect weather?

• Ocean Currents- any continuous flow of water across a broad path in the ocean-the current can be in any direction, but is usually horizontal

• Warmer water evaporates and forms clouds more easily than cold water. So, when a warm current travels father north than normally, it increases the chance of more rain and/ or snow.