Consider the anomalous conditions that accompany El Nino . Explain how two of th
ID: 115868 • Letter: C
Question
Consider the anomalous conditions that accompany El Nino . Explain how two of these conditions are physically consistent with a reduced east-to-west (EW) pressure gradient.
El Nino Reduced EW pressure gradient. Disruption of Walker cell: Reduced trade winds below and westerlies above. El Niño Conditions . .Reduced equatorial upwelling and Equator marine productivity. Weakening of equatorial cold tongue, i.e. warmer E-Pacific. Reduced thermocline and sea level 120E slopes. Upwelling water in the east is less cold and less nutrient rich. Thermocline . omencan Meteorological Society 80 w The above changes in pressure, wind, sea level, and upwelling are physically consistent with each other.Explanation / Answer
The El Nino conditions are as given in the El nino box and now its our turn to know how these conditions are physically consistent to each other.
As shown in the figure,the EW pressure gradient is low and due to the exchange of warm and cold water in the equatorial ocean north south wise the wind flow is also affected so the wind flows from east to west .By this kind of wind flow the temperature is balanced and equilibrium is maintained .If we use phase rule here it is a single component system and we have pressure constant as atmospheric pressure so the variable is temperature which is balanced by the wind flow ,so these two conditions physically consistent .