1 / 16

MID LATITUDE CYCLONES

MID LATITUDE CYCLONES. Grade 11 & 12 Climatology. What is a mid latitude cyclone. Explanation of the numbers above: The LP is caused by rising air. Air converges towards the LP area before rising. The centre is marked by an L on a synoptic weather map.

reina
Download Presentation

MID LATITUDE CYCLONES

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. MID LATITUDE CYCLONES Grade 11 & 12 Climatology

  2. What is a mid latitude cyclone

  3. Explanation of the numbers above: The LP is caused by rising air. Air converges towards the LP area before rising. The centre is marked by an L on a synoptic weather map. Air rotates in a clockwise direction around a LP centre (for the Southern hemisphere; the opposite occurs in the Northern hemisphere). Isobar readings decrease towards the centre. The rising air leads to cloudy weather / rain. How do cyclones behave

  4. Where do the mid latitude cyclones form? • These develop at the polar front, which is the meeting of cold polar air from the South, and warmer tropical air from the North (Southern Hemisphere). The cold easterly winds meet the warmer westerly winds at the polar front. The two air massess meet but they do not mix

  5. Formation at the polar front

  6. Initial Stage The meeting of these different winds creates a disturbance in the frontal surface which forms a wave in the polar front. The wave grows and intensifies, and forms a wedge of warm air penetrating the cold air. Low pressure forms at the point of the wave, and air begins to rotate in a clockwise direction (Southern Hemisphere).

  7. Initial Stage (continued)

  8. The Mature Stage • The warm westerlies push into the cold air as they are drawn clcockwise around the Low Pressure. • Where the warm air intrudes into the cold air a warm front is formed • The cold easterlies swing around due to the convergence and intrude into the warm air forming a cold front

  9. The Mature Stage (continued)

  10. Cross section of a Mature Cyclone

  11. Revision

  12. Influences • Further facts: • These weather systems move from West to East. • Mid latitude cyclones occur in groups or families (usually about 3 to 5 in a family). • They influence South Africa's weather: they bring rain to the S.W. Cape in winter and icy weather into the interior. • They are responsible for winter and early spring rain on the plateau thus filling farm dams and softening the soil for planting. • Remember:Cape Town is a winter rainfall area, due to the influence of the mid latitude cyclones. The mid latitude cyclone has different fronts and sectors; thus as it passes overhead the weather will change.

  13. Weather with the passage of a cyclone

  14. Weather • Pressure:Air pressure will increase as the cold front passes over you. Why?Because cold air is heavier and denser than warm air (thus has a higher pressure).

  15. Understand and interpret the cross-section of a mid latitude cyclone.

  16. The synoptic chart

More Related