Kelompok 04

Summary

This presentation explains the global climate phenomena of El Niño and La Niña, highlighting their effects on weather patterns, ecosystems, and economies. It covers the Walker circulation, where warm air rises in the Pacific and causes rainfall, and the contrasting weather impacts of El Niño (warming in the eastern Pacific) and La Niña (cooling in the same region). The presentation discusses the teleconnections, environmental impacts such as droughts and coral bleaching, and the models used for predicting these phenomena, including atmospheric, oceanic, and integrated models. Overall, it provides a comprehensive overview of how these climate events shape global weather and ecosystems.

Takeaways

• 😀 **Walker Circulation**: The movement of warm, moist air in the Pacific Ocean creates rainfall and influences global weather patterns.
• 🌍 **El Niño**: A global climate phenomenon where warming of sea surface temperatures in the eastern Pacific causes disruptions in weather patterns, typically every 2-7 years.
• 🌧️ **La Niña**: The opposite of El Niño, where cooler sea surface temperatures in the Pacific lead to different weather impacts, such as more rainfall in some regions and droughts in others.
• 🌐 **Teleconnection**: Refers to the global climate impact of El Niño and La Niña, affecting regions such as Southeast Asia, Australia, and the Americas by altering their seasonal weather.
• 🔥 **Environmental Impacts of El Niño**: Includes increased forest fires, coral bleaching, and shifts in fish migration patterns due to altered ocean temperatures.
• 💨 **Atmospheric Models**: Use mathematical simulations to predict weather patterns by modeling air circulation, temperature, and pressure, helpful for short-term forecasts.
• 🌊 **Oceanic Models**: Simulate changes in ocean temperatures and currents to understand the onset and effects of El Niño and La Niña events.
• 🔗 **Integrated Models**: Combine both atmospheric and oceanic models to provide a more comprehensive understanding of climate dynamics, although they require significant resources.
• 📊 **Statistical Models**: Utilize historical data to identify patterns and predict weather, offering an efficient way to forecast short-term weather but with less accuracy for extreme events.
• 🌎 **Global Weather Disruption**: El Niño and La Niña events have wide-reaching effects, from changing rainfall patterns in Indonesia to increased winter temperatures in parts of North America and the southern U.S.

Q & A

What is the Walker Circulation?

The Walker Circulation is the atmospheric circulation pattern that occurs over the equatorial Pacific Ocean. It involves warm, moist air rising over the western Pacific (near Indonesia), creating clouds and rainfall. The air then flows eastward at high altitudes before descending in the eastern Pacific. This circulation influences global weather patterns.

How does the phenomenon of El Niño occur?

El Niño is a climate phenomenon caused by the warming of sea surface temperatures in the central and eastern Pacific Ocean. This warming disrupts normal wind patterns and causes changes in atmospheric pressure, which affects global weather patterns. El Niño events typically occur every 2 to 7 years and last for 12 to 15 months.

What are the primary characteristics of El Niño?

El Niño is characterized by a periodic rise in sea surface temperatures in the central and eastern Pacific, a decrease in upwelling of cold water in the eastern Pacific, and a shift in atmospheric pressure between regions like Darwin, Australia, and Tahiti. These changes can cause widespread disruptions in global weather, such as droughts in Asia and wetter conditions in the Americas.

How does La Niña differ from El Niño?

La Niña is essentially the opposite of El Niño. It is characterized by cooler-than-normal sea surface temperatures in the central and eastern Pacific. This cooling leads to a strengthening of the typical Walker Circulation, with stronger trade winds and more upwelling in the eastern Pacific. La Niña often results in drier conditions in the Americas and wetter conditions in Southeast Asia and Australia.

What is meant by 'teleconnection' in the context of El Niño?

Teleconnection refers to the distant relationship between El Niño events in the Pacific Ocean and weather patterns in other parts of the world. For instance, El Niño can cause changes in rainfall patterns, leading to droughts or floods in regions far from the Pacific, such as Southeast Asia, Australia, and the Americas.

What impacts does El Niño have on Southeast Asia and Australia?

During an El Niño event, Southeast Asia and Australia typically experience extended and intensified dry seasons, which can lead to droughts, wildfires, and water shortages. This is due to the disruption in normal atmospheric circulation and a reduction in rainfall.

How does El Niño affect the United States?

El Niño tends to cause warmer and drier winters in the western United States, particularly in California, while increasing rainfall in the southeastern regions, such as Florida. These shifts in weather can lead to floods in some areas and droughts or wildfire risks in others.

What environmental consequences are linked to El Niño?

El Niño can cause a range of environmental issues, such as coral bleaching due to warmer ocean temperatures, forest fires due to prolonged dry conditions, and disruptions in marine life, including the migration patterns of fish. The changes in water temperature can reduce fish populations and damage ecosystems.

What are the different types of climate models used to predict El Niño events?

There are several types of models used to predict El Niño events, including atmospheric models, oceanic models, integrated models (which combine atmospheric and oceanic data), and statistical models. Each model type has its strengths and challenges, with integrated models providing the most comprehensive view by simulating both ocean and atmospheric processes.

How are El Niño predictions made using climate models?

El Niño predictions are typically made by comparing observed sea surface temperature anomalies in the Pacific with model predictions. Models may use historical data to identify patterns and predict future events. A strong correlation between predicted and observed anomalies helps improve the accuracy of these forecasts.