Winds: DGCA Aviation Meteorology questions

Here wind is a balance of forces: the pressure gradient pushes, Coriolis turns, curved isobars add a centrifugal effect and friction drags near the surface. Drift and altimeter error both follow from where the low pressure lies.

The 35 questions favour theory over local names: geostrophic and gradient wind, the change between the surface and 2000 ft, drift and altitude problems, and the Föhn and the Bora. Exam sessions have chosen 2 of these wind questions.

For the same pressure gradient the geostrophic wind is stronger at lower latitudes, because Coriolis force weakens towards the equator. In the Southern Hemisphere the surface wind is veered from the 2000 ft wind, the reverse of the northern rule.