AP Environmental Science Flashcards: El Nino And La Nina

What this deck covers

This deck focuses on El Nino And La Nina, giving you a quick way to review the definitions, rules, and examples that matter most for AP Environmental Science.

How to use these flashcards

Work through these flashcards in short sessions. Try to answer each prompt before flipping the card, then revisit any cards you miss until the explanation feels automatic.

Flashcard 1: 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 2: What is La Niña?

Answer: A climate pattern characterized by cooling of ocean surface waters in the central and eastern Pacific. This occurs when trade winds strengthen, increasing upwelling of cold water.

Flashcard 3: 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 4: 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 5: 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 6: What atmospheric pressure pattern is associated with La Niña?

Answer: Increased pressure over the eastern Pacific and decreased pressure over the western Pacific. This pressure pattern strengthens trade winds during La Niña.

Flashcard 7: 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 8: 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 9: 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 10: Which ENSO phase often leads to increased snow in the Pacific Northwest?

Answer: La Niña. Cooler temperatures and northern jet stream enhance snowfall.

Flashcard 11: Identify the typical effect of El Niño on the fisheries of the west coast of South America.

Answer: Decline in fish populations due to warmer, nutrient-poor waters. Warm water suppresses upwelling of nutrient-rich cold water.

Flashcard 12: What happens to the Walker Circulation during El Niño?

Answer: The Walker Circulation weakens or reverses. Reduced pressure gradient disrupts normal atmospheric circulation.

Flashcard 13: 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 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 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 16: 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 17: Identify the effect of La Niña on winter temperatures in the northern United States.

Answer: Colder than normal winter temperatures. Northward jet stream shift allows Arctic air to penetrate south.

Flashcard 18: Identify the primary mechanism driving the ENSO cycle.

Answer: Interaction between oceanic and atmospheric processes in the Pacific. Ocean-atmosphere feedback loops create this oscillating climate pattern.

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: 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 21: 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 22: What happens to the Walker Circulation during La Niña?

Answer: The Walker Circulation strengthens. Enhanced pressure gradient intensifies normal circulation patterns.

Flashcard 23: 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 24: What is the effect of La Niña on rainfall in Southern California?

Answer: Decreased rainfall. Northward jet stream diverts storms away from the region.

Flashcard 25: Which ENSO phase often leads to increased snow in the Pacific Northwest?

Answer: La Niña. Cooler temperatures and northern jet stream enhance snowfall.

Flashcard 26: 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 27: 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 28: 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 29: Which ENSO phase is associated with coral bleaching events?

Answer: El Niño. Warmer waters stress corals, causing them to expel symbiotic algae.

Flashcard 30: Which ENSO phase often results in drought in Australia?

Answer: El Niño. Weakened Walker Circulation reduces moisture transport to Australia.

Flashcard 31: Identify the effect of La Niña on winter temperatures in the northern United States.

Answer: Colder than normal winter temperatures. Northward jet stream shift allows Arctic air to penetrate south.

Flashcard 32: 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.

Flashcard 33: 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 34: 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 35: 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 36: 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 37: 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 38: 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 39: 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 40: 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 41: 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 42: What is the effect of La Niña on rainfall in Southern California?

Answer: Decreased rainfall. Northward jet stream diverts storms away from the region.

Flashcard 43: What atmospheric pressure pattern is associated with La Niña?

Answer: Increased pressure over the eastern Pacific and decreased pressure over the western Pacific. This pressure pattern strengthens trade winds during La Niña.

Flashcard 44: 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 45: 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 46: 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 47: 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 48: 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 49: Which ENSO phase is associated with coral bleaching events?

Answer: El Niño. Warmer waters stress corals, causing them to expel symbiotic algae.

Flashcard 50: What happens to the Walker Circulation during El Niño?

Answer: The Walker Circulation weakens or reverses. Reduced pressure gradient disrupts normal atmospheric circulation.

Flashcard 51: 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 52: 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 53: Identify the effect of El Niño on winter temperatures in the northern United States.

Answer: Warmer than normal winter temperatures. Southward jet stream shift brings warm Pacific air inland.

Flashcard 54: 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 55: Which ENSO phase often results in floods in Australia?

Answer: La Niña. Enhanced Walker Circulation increases moisture transport to Australia.

Flashcard 56: 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 57: What happens to the Walker Circulation during La Niña?

Answer: The Walker Circulation strengthens. Enhanced pressure gradient intensifies normal circulation patterns.

Flashcard 58: Identify the effect of El Niño on winter temperatures in the northern United States.

Answer: Warmer than normal winter temperatures. Southward jet stream shift brings warm Pacific air inland.

Flashcard 59: 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 60: Which ENSO phase often results in drought in Australia?

Answer: El Niño. Weakened Walker Circulation reduces moisture transport to Australia.

Flashcard 61: 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 62: 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 63: Identify the typical effect of El Niño on the fisheries of the west coast of South America.

Answer: Decline in fish populations due to warmer, nutrient-poor waters. Warm water suppresses upwelling of nutrient-rich cold water.

Flashcard 64: 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 65: 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 66: What is La Niña?

Answer: A climate pattern characterized by cooling of ocean surface waters in the central and eastern Pacific. This occurs when trade winds strengthen, increasing upwelling of cold water.

Flashcard 67: 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 68: 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 69: 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.

Flashcard 70: 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 71: Identify the primary mechanism driving the ENSO cycle.

Answer: Interaction between oceanic and atmospheric processes in the Pacific. Ocean-atmosphere feedback loops create this oscillating climate pattern.

Flashcard 72: 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 73: 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 74: 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 75: 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 76: 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 77: 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 78: Which ENSO phase often results in floods in Australia?

Answer: La Niña. Enhanced Walker Circulation increases moisture transport to Australia.