Lectures_11b - Hurricanes Hurricane Carlotta moving...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Fig. 11-CO, p.292 Hurricanes Hurricane Carlotta moving northeastward parallel to the coast of Mexico during June, 2000. With sustained winds of 100 knots and a central pressure near 95.0 kPa, Carlotta ranks as a Category 3 hurricane on the Saffir-Simpson hurricane scale.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Fig. 11-1, p.294 A tropical wave (also called an easterly wave) as shown by the bending of streamlines—lines that show wind flow patterns. (The heavy dashed line is the axis of the trough.) The wave moves slowly westward, bringing fair weather on its western side and showers on its eastern side.
Background image of page 2
Fig. 11-2, p.295 Hurricane Elena over the Gulf of Mexico, about 130 km as photographed from the space shuttle Discovery during September, 1985. Because this storm is situated north of the equator, surface winds are blowing counterclockwise about its centre (eye). The central pressure of the storm is 95.5 kPa, with sustained winds of 195 km/hr near its eye.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Once a tropical storm (low pressure) begins to form, the convergence pulls in moisture evaporating from the sea surface generally above 27°C The lifting, cooling and condensation converts moisture into heat within thunderstorms . This heat release strengthens the inflow further, resulting in greater evaporation from the ocean. If this positive feedback continues it can lead to the development of a hurricane or typhoon . Bands of thunderstorms spiral toward the eye , a column of descending air at the heart of the cyclone (this is unlike a wave cyclone). Hurricane development
Background image of page 4
A hurricane is an intense rotating storm system that forms over warm tropical waters typically in the late summer or early fall . Hurricanes are circular in shape, ranging from 300 to 1,000 km across, and have winds over 118 km/h within 50 kilometres of the centre. The formation of a hurricane requires a low pressure disturbance over a large expanse of warm water. The evaporation of this water will intensify the resulting storm. This formation must be far enough from the equator so that winds will circulate around a centre of low pressure due to the Coriolis force. The Coriolis force is too weak near the Equator to create the needed rotation. There must be low vertical wind shear Hurricane Development
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The hurricanes that strike North America form in the tropical North Atlantic and Caribbean and move on a westerly to northerly track, steered by the prevailing winds. They strike the mainland on either the Gulf or Atlantic coasts. The tropical disturbance stage of hurricane development is characterized by a collection of thunderstorms forming in the easterly flow over warm tropical waters (27C) with only a slight rotation. The tropical depression
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 06/05/2010 for the course EATS 1011 taught by Professor Johnm during the Winter '10 term at York University.

Page1 / 40

Lectures_11b - Hurricanes Hurricane Carlotta moving...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online