All flashcards
Flashcard 1: Which phase of ENSO is typically associated with reduced hurricane activity in the Atlantic?
Answer: El Niño. El Niño increases wind shear that disrupts hurricane formation.
Flashcard 2: What atmospheric pressure pattern is associated with El Niño?
Answer: Decreased pressure over the eastern Pacific and increased pressure over the western Pacific. This pressure pattern creates weakened trade winds during El Niño.
Flashcard 3: Identify the term for the entire cycle of El Niño and La Niña events.
Answer: El Niño-Southern Oscillation (ENSO). ENSO encompasses both oceanic and atmospheric components of this cycle.
Flashcard 4: Identify the impact of La Niña on sea surface temperatures in the central Pacific.
Answer: Sea surface temperatures decrease. Enhanced upwelling brings cold deep water to the surface.
Flashcard 5: Which ENSO phase often leads to increased snow in the Pacific Northwest?
Answer: La Niña. Cooler temperatures and northern jet stream enhance snowfall.
Flashcard 6: What is the Walker Circulation?
Answer: A conceptual model of air flow in the equatorial Pacific associated with trade winds. This circulation drives normal east-to-west surface wind patterns.
Flashcard 7: What is the Southern Oscillation Index (SOI)?
Answer: A measure of the difference in air pressure between Tahiti and Darwin. SOI quantifies atmospheric pressure oscillation across the Pacific.
Flashcard 8: How does El Niño affect the monsoon season in India?
Answer: It typically weakens the monsoon, leading to drier conditions. Altered Walker Circulation reduces moisture transport to India.
Flashcard 9: Identify one economic impact of La Niña.
Answer: Increased costs for heating due to colder winters. Colder temperatures increase energy demand for space heating.
Flashcard 10: Identify the typical time interval between El Niño events.
Answer: Every 2 to 7 years. This irregular cycle varies in timing but follows this general pattern.
Flashcard 11: What happens to the Walker Circulation during La Niña?
Answer: The Walker Circulation strengthens. Enhanced pressure gradient intensifies normal circulation patterns.
Flashcard 12: What is the typical duration of an El Niño event?
Answer: 9 to 12 months. Most El Niño events peak and decay within this timeframe.
Flashcard 13: What is El Niño?
Answer: A climate pattern characterized by warming of ocean surface waters in the central and eastern Pacific. This occurs when trade winds weaken, reducing upwelling of cold water.
Flashcard 14: Which direction do the trade winds blow during El Niño?
Answer: Trade winds weaken and may reverse, blowing west to east. Weakened pressure gradient reduces normal easterly trade wind flow.
Flashcard 15: Which direction do the trade winds blow during La Niña?
Answer: Trade winds strengthen, blowing east to west. Strong pressure gradient enhances normal easterly trade wind flow.
Flashcard 16: State the impact of El Niño on global weather patterns.
Answer: Increased rainfall in the central and eastern Pacific, droughts in the western Pacific. Warm waters shift eastward, altering global precipitation patterns.
Flashcard 17: Which ENSO phase often results in floods in Australia?
Answer: La Niña. Enhanced Walker Circulation increases moisture transport to Australia.
Flashcard 18: Identify one economic impact of El Niño.
Answer: Damage to agriculture due to altered weather patterns. Extreme weather events disrupt crop yields and food production.
Flashcard 19: State the impact of La Niña on global weather patterns.
Answer: Drier conditions in the central and eastern Pacific, wetter conditions in the western Pacific. Cold waters persist in east, maintaining normal precipitation patterns.
Flashcard 20: Which ocean is primarily affected by El Niño and La Niña?
Answer: Pacific Ocean. The Pacific spans the equatorial region where ENSO events originate.
Flashcard 21: What is the effect of La Niña on the jet stream over North America?
Answer: The jet stream typically shifts northward. Northern shift keeps storm tracks away from southern regions.
Flashcard 22: Which ENSO phase is associated with coral bleaching events?
Answer: El Niño. Warmer waters stress corals, causing them to expel symbiotic algae.
Flashcard 23: What is the primary indicator used to predict ENSO events?
Answer: Sea surface temperature anomalies in the equatorial Pacific. Temperature changes in specific Pacific regions signal ENSO development.
Flashcard 24: How does La Niña affect the monsoon season in India?
Answer: It typically strengthens the monsoon, leading to wetter conditions. Enhanced Walker Circulation increases moisture transport to India.
Flashcard 25: Which phase of ENSO is typically associated with hurricanes in the Atlantic?
Answer: La Niña. La Niña's cooler waters reduce wind shear that inhibits hurricanes.
Flashcard 26: What is the typical effect of La Niña on the fisheries of the west coast of South America?
Answer: Improved fish populations due to cooler, nutrient-rich waters. Strong upwelling brings nutrients to surface, supporting fish growth.
Flashcard 27: What is the typical duration of a La Niña event?
Answer: 1 to 3 years. La Niña events tend to persist longer than El Niño events.
Flashcard 28: What is the effect of El Niño on the jet stream over North America?
Answer: The jet stream typically shifts southward. Southern shift brings storms and rain to southern regions.
Flashcard 29: Identify the impact of El Niño on sea surface temperatures in the central Pacific.
Answer: Sea surface temperatures increase. Reduced upwelling allows surface waters to warm significantly.
Flashcard 30: What is the effect of El Niño on rainfall in Southern California?
Answer: Increased rainfall. Southward jet stream carries moisture-laden storms to the region.