What are El Niño and La Niña?
Explanation: The correct answer is C) Alternating phases of ocean-atmosphere interaction in the tropical Pacific. El Niño and La Niña are the two alternating phases of a climate pattern known as the El Niño-Southern Oscillation (ENSO). During El Niño, warmer-than-average sea surface temperatures occur in the central and eastern tropical Pacific Ocean, while La Niña is characterized by cooler-than-average sea surface temperatures in the same region.
What causes the occurrence of El Niño and La Niña?
Explanation: The correct answer is D) Interactions between ocean and atmosphere. El Niño and La Niña are primarily caused by interactions between the ocean and the atmosphere in the tropical Pacific region. These interactions involve changes in oceanic and atmospheric circulation patterns, which influence sea surface temperatures and atmospheric conditions, resulting in the development of either El Niño or La Niña events.
What are the typical effects of El Niño on global weather patterns?
Explanation: The correct answer is D) All of the above. El Niño can have various effects on global weather patterns. It is often associated with increased hurricane activity in the Atlantic Ocean, widespread droughts in tropical regions such as Australia and Southeast Asia, and below-average rainfall in parts of South America. These impacts arise from the altered atmospheric circulation patterns and changes in oceanic conditions associated with El Niño events.
Which of the following is a characteristic of La Niña events?
Explanation: The correct answer is D) Increased ocean upwelling along the coast of South America. La Niña events are characterized by cooler-than-average sea surface temperatures in the central and eastern tropical Pacific, which result in increased ocean upwelling along the coast of South America. This upwelling brings nutrient-rich cold waters to the surface, promoting the growth of marine life and influencing local weather patterns.
How often do El Niño and La Niña events occur?
Explanation: The correct answer is B) Every year. El Niño and La Niña events occur on average every two to seven years, with some variations in the time intervals between events. The occurrence of El Niño and La Niña is part of the natural climate variability known as the El Niño-Southern Oscillation (ENSO), and their frequency and intensity can have significant impacts on weather patterns and climate conditions around the world.