Currents & Climate Ch 14.2
Warm-water currents i.e. Gulf Stream Creates mild climate at high latitudes such as British Isles (much warmer than Newfoundland which is at the same latitude)
Cold-water currents i.e. California Current Creates cooler climate in WA, OR, CA Much cooler than inland climates
Upwelling 1. surface water is blown off shore 2. cold water from ocean floor is pulled upward to replace the warm surface water 3. this deep water brings nutrients from ocean floor 4. phytoplankton flourishes, so this helps support healthy fisheries
El Nino El Nino Southern Oscillation (ENSO) Trade winds relax Upwelling slows on S. American coast Thermocline is deeper Nutrient supply decreases Fisheries decline
Worldwide results of ENSO Rains less in the western Pacific Rains more near Peru Drought in Indonesia & Australia Warmer, wetter winters in SE USA
El Nino Typically last months Occur every 3-7 years
Effects of El Nino Flash floods Mudslides (i.e. California) Droughts in Indonesia & Australia Drought = crop failure
La Nina Cooler than normal sea-surface temps in tropical Pacific Easterly trades strengthen Upwelling intensifies Indonesia & Australia are wetter Dries in SE USA, SW USA & Plains of USA Warm water is abnormally deep in W. Pacific
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