ATMOSPHERIC CIRCULATION AND WEATHER SYSTEMS Flashcards
The decrease in vertical pressure amounts to
about 1 mb for each 10 m increase in elevation.
In the northern hemisphere in winter pressure belts move
southwards and in the summer northwards
the horizontal winds near the earth surface respond to the combined effect of three forces –
the pressure gradient force, the frictional force and the Coriolis force
angle between the pressure gradient force, and the Coriolis force
perpendicular
angle between the pressure gradient force, and isobar
perpendicular
When isobars are straight and when there is no
friction, the pressure gradient force is balanced
by the Coriolis force and the resultant wind
blows parallel to the isobar
Geostrophic wind
cyclone in northern hemisphere direction
Anticlockwise
cyclone in southern hemisphere direction
clockwise
cells from equator to poles
Hadley cell, Ferrel cell , polar cell
El Nino
El Niño is a climate pattern that describes the unusual warming of surface waters in the eastern equatorial Pacific Ocean .
appearance of warm water off the coast of Peru is known as the El Nino.
The warm water of the central Pacific Ocean slowly drifts towards South American coast and replaces the cool Peruvian current
valley breeze
During daytime, wind blows up in the valley
Katabatic wind
The cool air, of the high plateaus and ice fields draining into the valley
an airmass.
The air with distinctive characteristics
in terms of temperature and humidity
following types of airmasses are recognised:
(i) Maritime tropical
(mT); (ii) Continental tropical (cT); (iii) Maritime
polar (mP); (iv) Continental polar (cP);
(v) Continental arctic (cA).
Extra tropical cyclones move from
west to east
