El Niņo and La Niņa are the names for two particular sets of meteorological conditions which occur in the Pacific Ocean. Although these conditions only occur in the Pacific, they affect the weather over large areas of the globe.
This exercise looks at the normal weather conditions in the Pacific Ocean. We will then look at how these conditions change during El Niņo and La Niņa events.
Exercise: Look at the following map and describe the situation when El Niņo conditions are not present.
1. The Pacific, pressure system and ocean currents, normal conditions map by design agency "Zur Gestaltung-Nürnberg", modified by Julia Heres Please click to enlarge!
Numbers in the map above
1: Northern Tropics (23.5 °N) 2: Southern Tropic (23.5 °S) 3: North America (Mexico), and off shore: cold California stream (white arrows) 4: South America (Peru), and off shore: cold Humboldt stream (white arrows) 5: High Pressure over the Easter Islands
Look at the map above.
What is correct?
1) Air pressure in the eastern part of the Pacific is ...
a) relatively high.
b) relatively low.
c) the same as in the western part.
d) the same as in the Caribbean.
2) The high pressure area over the Easter Islands is ...
a) destabilised by the warm ocean current off the Chilean and Peruvian coast.
b) stabilised by the warm ocean current off the Chilean and Peruvian coast.
c) destabilised by the cold ocean current off the Chilean and Peruvian coast.
d) stabilised by the cold ocean current off the Chilean and Peruvian coast.
3) Air pressure over Australia and South East Asia is ...
a) relatively low.
b) relatively high.
c) the same as in the eastern part.
d) the same as over Hawaii.
About this page:
author: Dr. Helmut Schrettenbrunner - University of Nürnberg, Germany educational reviewing: Dr. Yvonne Schleicher , Julia Heres - University of Nürnberg, Germany last update: 2003-09-08
