La Niña Predictions and Climate Impacts in 2024

As 2024 approaches, climate experts are analysing the absence of La Niña, climate phenomenon. Predictions for La Niña’s emergence have not materialised, raising concerns about its implications for global weather patterns. This year, the absence of La Niña may contribute to 2024 being the warmest year on record, surpassing 2016.

About La Niña

La Niña is part of the El Niño Southern Oscillation (ENSO). ENSO consists of three phases – El Niño, La Niña, and neutral. Each phase influences global weather patterns. La Niña is characterised by cooler sea temperatures in the central and eastern Pacific Ocean. It typically leads to increased rainfall in regions like India and lower temperatures.

Current Ocean Conditions

Recent data from the National Oceanic and Atmospheric Administration (NOAA) indicates near-to-below average sea surface temperatures in the equatorial Pacific. The Oceanic Nino Index (ONI) remains at minus 0.3 degrees Celsius, suggesting ENSO-neutral conditions. Predictions for La Niña have shifted from earlier expectations of a strong emergence to a weak and brief occurrence.

Reasons for Missed Predictions

Weather models generally perform better with strong temperature changes. This year, the subtle variations in ocean temperatures have led to inaccurate forecasts. The interaction between the ocean and atmosphere has not aligned with typical patterns, contributing to the failure of La Niña to materialise.

Ocean-Atmosphere Coupling

The interaction between ocean and atmosphere is crucial for determining ENSO phases. This year, the expected coupling did not occur. El Niño conditions have persisted into 2024, affecting the temperature dynamics in the Pacific. The result is a continuation of ENSO-neutral conditions rather than a transition to La Niña.

Westerly Wind Anomalies

Westerly wind anomalies have been prevalent during critical months when La Niña was expected to develop. These winds disrupt the typical conditions needed for La Niña, preventing its establishment. This atmospheric behaviour has contributed to the ongoing neutral phase.

Impact on Indian Monsoons

The interplay between ENSO and the Indian Summer monsoon is . This year, the monsoon experienced above-normal rainfall, coinciding with ENSO-neutral conditions. A robust monsoon can influence atmospheric conditions, potentially delaying the onset of La Niña.

Future Projections

Experts predict that any weak La Niña that may occur between December and February will likely be short-lived. It may transition back to ENSO-neutral conditions by March-May 2025. This implies minimal impact on the Indian winter and ongoing weather patterns.

Questions for UPSC:

1. Examine the role of the El Niño Southern Oscillation in global climate patterns.
2. Discuss in the light of current climate trends how the absence of La Niña might affect rainfall patterns in India.
3. Analyse the significance of ocean-atmosphere coupling in predicting climate phenomena like La Niña.
4. With suitable examples, discuss the relationship between monsoon patterns and ENSO phases.

Answer Hints:

1. Examine the role of the El Niño Southern Oscillation in global climate patterns.

1. ENSO consists of three phases – El Niño, La Niña, and neutral, each impacting global weather differently.
2. El Niño typically leads to warmer sea surface temperatures and altered precipitation patterns, causing droughts in some regions.
3. La Niña is associated with cooler ocean temperatures, resulting in increased rainfall and cooler temperatures in affected areas.
4. ENSO influences atmospheric circulation, which can lead to extreme weather events like hurricanes and floods.
5. The irregular cycles of ENSO occur every two to seven years, making long-term predictions challenging.

2. Discuss in the light of current climate trends how the absence of La Niña might affect rainfall patterns in India.

1. La Niña typically brings increased rainfall to India, especially during the monsoon season.
2. The current ENSO-neutral conditions indicate a lack of cooling in the Pacific, which may lead to reduced monsoon rainfall.
3. Experts predict that without La Niña, India may experience higher temperatures and less predictable rainfall patterns.
4. Current trends suggest that 2024 could be warmer, potentially affecting crop yields and water resources.
5. The absence of La Niña might lead to erratic weather patterns, complicating agricultural planning in India.

3. Analyse the significance of ocean-atmosphere coupling in predicting climate phenomena like La Niña.

1. Ocean-atmosphere coupling is crucial for understanding the interactions that dictate ENSO phases.
2. This year, the expected coupling did not occur, leading to persistent ENSO-neutral conditions.
3. Effective coupling typically results in clearer predictions of La Niña or El Niño events based on sea surface temperatures.
4. Disruptions in this coupling can lead to inaccurate forecasts and unexpected climate outcomes.
5. About these interactions is essential for improving climate models and making accurate predictions.

4. With suitable examples, discuss the relationship between monsoon patterns and ENSO phases.

1. ENSO phases influence the Indian monsoon; El Niño often leads to weaker monsoons with below-average rainfall.
2. Conversely, La Niña is associated with stronger monsoons and above-average rainfall, enhancing agricultural productivity.
3. For instance, the 2016 El Niño resulted in drought conditions across India, affecting crop yields and water availability.
4. This year’s ENSO-neutral phase coincided with above-normal rainfall, demonstrating the variability of monsoon patterns.
5. The interplay between monsoon and ENSO phases is vital for predicting weather extremes and planning for agriculture.