El Nino and Atmospheric Effects

The video tutorial explains the phenomena of El Nino and La Nina, focusing on their impact on atmospheric and oceanic conditions. It describes normal conditions, characterized by the Walker Circulation, and contrasts them with La Nina, which intensifies normal patterns, and El Nino, which disrupts them. The tutorial highlights the effects of these phenomena on weather patterns, particularly in the Pacific region, and their broader implications, such as droughts and storms. It also touches on historical knowledge of these patterns by indigenous navigators.

What is the primary focus of the figure discussed in the introduction?

• The impact of El Nino on global temperatures

• The relationship between El Nino, La Nina, and air pressure changes

• The effect of trade winds on ocean currents

• The role of the thermocline in the Atlantic Ocean

Under normal conditions, where is the air pressure higher?

• Pap, Tahiti

• Darwin, Australia

• The Western Pacific

• The Eastern Pacific

What is the Walker circulation?

• A pattern of air movement in the Atlantic Ocean

• A circulation pattern involving east to west surface winds and west to east upper atmosphere winds

• A type of ocean current in the Indian Ocean

• A weather pattern specific to the Arctic region

What happens to the thermocline during strong La Nina conditions?

• It deepens in the Eastern Pacific

• It becomes shallower in the Eastern Pacific

• It remains unchanged

• It deepens in the Western Pacific

What is the Southern Oscillation Index?

• A measure of sea surface temperature

• A measure of air pressure differences between Tahiti and Darwin

• An index of ocean salinity

• An index indicating the strength of trade winds

How do trade winds behave during an El Nino event?

• They strengthen and blow from east to west

• They relax or reverse direction

• They remain constant

• They blow from north to south

What historical evidence is there for the awareness of El Nino?

• Medieval European manuscripts

• Ancient Greek texts

• Journals of Captain Cook

• Chinese historical records

What is a significant consequence of El Nino on Southern California?

• Decreased humidity

• Milder winters

• Increased drought conditions

• Heavy rainfall and storms

What happens to fisheries during an El Nino event?

• They thrive due to increased nutrients

• They experience a boom in fish population

• They remain unaffected

• They decline due to a lack of upwelling

What is a Kelvin wave in the context of El Nino?

• A type of ocean wave that travels westward

• A wave that propagates eastward across the Pacific Ocean

• A wave that affects the Atlantic Ocean

• A wave that only occurs during La Nina