Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Pressure: Highs and Lows Name: ___________________________ Date: _________________ Pressure is measured in milibars using a barometer. On a map we can look for areas of similar pressure and connect them with lines. These lines are called isobars. You will see many Isobars zigzagging across the U.S. on the map. Notice that isobars curve and never cross each other! If the numbers decrease as milibars move away from the center, it is a high pressure system. If the numbers increase as milibars move away from the center, it is a low pressure system. 1. Label the areas of high pressure centers with an H in the box and low pressure centers with an L in the box. 2. Based on yesterday’s research, what type of weather will they be having in Missouri (*)? clear skies and sunshine OR cloudy skies and precipitation 3. Based on yesterday’s research, what type of weather will they be having in Montana (@)? clear skies and sunshine OR cloudy skies and precipitation @ * CUA: The pressure in a high is greater than the surrounding air. Its winds blow out. The pressure in a low is lower than the surrounding air so wind is blowing inward. In the northern hemisphere the wind blows clockwise, called an “anticyclone,” around centers of high pressure. The wind blows counterclockwise, called a “cyclone” around lows. It is the opposite in the southern hemisphere. 4. Label the wind systems on the right as cyclone and anticyclone. 5. Draw arrows for the wind directions on the map around the H and L of the high and low pressure systems. Wind Strength Remember that wind is the horizontal movement of air from an area of high pressure to an area of lower pressure. The strength of the wind is determined by changes in the pressure, called the pressure gradient. A large change in pressure over a short distance (shown on a weather map as lines very close together) would indicate strong winds. On a weather map, isobars that are close together indicate a strong pressure gradient. The drawing of the cyclone and anticyclone reminds you of the direction of the wind within a pressure system. Complete the map below again…it’s the same one as the front. 6. Label the area of high pressure centers with an H and low pressure centers with an L. 7. Indicate on your map where you expect the strongest winds with a large “S.” This is where the lines are closest together. 8. Write an “A” next to the “S” if it is an anticyclone. Write an “AC next to the “S” if it is a cyclone. 9. Find Maryland on the map. Based on the systems you identified, describe the shift in wind and weather as the system approaches you from west to east. __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ Use the information and map below to answer questions 10-13. The map below shows a low pressure system (labeled ‘L’) and a high pressure system (labeled ‘H’) over the United States. AIR PRESSURE SYSTEMS OVER THE UNITED STATES H L 10. The large ‘H’ represents the center of a high pressure system. Which most likely describes the properties of the air in the high pressure system? A B C D warm, moist air warm, dry air cool, moist air cool, dry air 12. The large ‘L’ represents the center of a low pressure system. Which best describes the vertical and horizontal motions of air at the low pressure center? A B C D 13. Winds along the surface between the pressure systems will generally move _______. A B C D 14. Air is falling and moving inward at the surface. Air is falling and spreading outward at the surface. Air is rising and moving inward at the surface. Air is rising and spreading outward at the surface. from the high pressure center to the low pressure center from the low pressure center to the high pressure center from high elevations to low elevations from the ocean to the continent Which location is likely to have the greatest air pressure? A B C D Top of Earth’s atmosphere Upper surface of clouds Middle of clouds Surface of the Earth