11. These storms derive their energy from the sharp temperature contrasts in the middle latitudes . 12. Nearly all ice caps in the middle latitudes of Africa and South America have disappeared. 13. In middle latitudes , it is more accurate to speak of ozone depletion rather than holes. 14. Unlike the westerlies in the middle latitudes , the polar easterlies are often weak and irregular. 15. Disturbances that have features of tropical and middle latitude cyclones are sometimes called subtropical storms. 16. Lineated valley fill is common in the middle latitudes , especially near the northern dichotomy boundary. 17. Members of this family occur throughout the oceans of the world at low to middle latitudes . 18. Disturbances that share features of both tropical and middle latitude cyclones are sometimes called sub-tropical storms. 19. The oceanic climates occur in the higher middle latitudes , between 45?and 60?north and south latitude. 20. Typically, several days after the typhoon's effects reach the middle latitudes , eastern North America turns much cooler.
