Current Affairs 13-August-2023 (The Hindu)

Corals and Coral Reef Conservation

Corals

• Corals are marine Invertebrates that occur along with Zooxanthellae.

• Zooxanthellae: Microscopic algae that reside on corals, forming a symbiotic relationship.

• Zooxanthellae assist corals in obtaining nutrients through photosynthesis.
• Corals offer a safe environment for Zooxanthellae to reside.
• Corals are typically white in color.
• The bright color of corals is due to colorful zooxanthellae.
• Coral bleaching (whitening of corals) occurs when zooxanthellae are expelled from corals due to prolonged heatwaves.

 

Steps taken by the Indian Govt to conserve coral reefs in India

• Inclusion of all corals in Schedule 1 of the Wildlife Protection Act, 1972.
• Harvesting of corals is punishable by imprisonment and fine.
• Enactment of coastal regulation zones under the Environment Protection Act, 1986.
• CRZ 1 includes marine parks, marine sanctuaries, mangroves, corals/coral reefs.
• Mining of corals is prohibited in India.
• Restriction on construction of structures in CRZ 1.
• Declaration of marine protected areas.

 

Marine Protected Areas in Peninsular India

• Exploitation of corals is prohibited in marine protected areas.
• Examples: Waters in Andaman & Nicobar Islands, Gulf of Mannar in Tamil Nadu.

 

El Nino and La Nina

El Niño–Southern Oscillation (ENSO)

The El Niño–Southern Oscillation (ENSO) occurs in

Three phases:

• 1.Neutral
• 2.El Nino
• 3.La Nina

Neutral Phase

• The neutral phase of ENSO refers to a state in which sea surface temperatures in the central and eastern Pacific Ocean are close to their long-term average.
• During this phase, there is no significant warming (El Niño) or cooling (La Niña) of the ocean waters.

El Nino

• Periodic warming of sea surface temperatures in the central and eastern equatorial Pacific Ocean.
• Disrupts oceanic circulation patterns and leads to atmospheric and climatic changes.
• Combined with the Southern Oscillation, it forms the El Nino-Southern Oscillation (ENSO), a powerful climate driver.
• ENSO refers to the cyclical swing between El Niño and La Niña (the opposite phase, characterized by cooler sea surface temperatures).
• ENSO has a significant influence on global weather patterns, including monsoon rainfall in India.

El Nino's Global Impact

• Oceanic and atmospheric coupling leads to cascading effects on global climate systems.
• Causes worldwide weather anomalies, such as droughts (Australia, Africa) and heavy rainfall (South America).
• Contributes to short-term global temperature fluctuations.
• Elevated sea temperatures during El Nino events lead to coral bleaching and disrupt marine ecosystems.
• Economic consequences affect agriculture, fisheries, water resources, and infrastructure.

El Nino's Impact on India

• Weakens the Indian monsoon, leading to reduced rainfall and drought conditions.
• Reduced rainfall affects crop yields, impacting food production and farmers' income.
• Water scarcity results from decreased monsoon rainfall, affecting drinking water and irrigation.
• Hydropower generation is impacted, increasing reliance on other energy sources.
• Economic challenges arise due to poor agricultural output and water scarcity.
• Drought conditions can lead to waterborne diseases and malnutrition.
• Infrastructure stress occurs due to water scarcity and flooding.
• Adaptation and resilience strategies, like drought-resistant crops and water management, are crucial.
• Government response includes water conservation, drought relief, and climate-resilient policies.
• Community awareness empowers proactive measures to reduce vulnerabilities.

La Nina

• Counterpart to El Nino; represents cooler-than-average sea surface temperatures in the central and eastern equatorial Pacific Ocean.
• Affects global climate patterns with contrasting effects compared to El Nino.
• Often follows El Niño and is part of the El Nino-Southern Oscillation (ENSO) climate cycle.

Global Impact of La Nina

• Cooling of sea surface temperatures influences atmospheric circulation patterns, leading to distinct weather anomalies worldwide.
• Causes increased rainfall in some regions, potentially resulting in flooding and wetter-than-normal conditions.
• Can lead to drought conditions in other areas due to shifts in atmospheric circulation.
• Affects hurricane activity in the Atlantic and Pacific, with increased likelihood of more intense hurricanes in the Atlantic.
• Contrasts El Nino's global temperature fluctuations, often contributing to cooler global temperatures during its presence.

La Nina's Impact on India

• Typically strengthens the Indian monsoon, leading to above-average rainfall and wetter conditions.
• Enhanced monsoon can lead to increased agricultural productivity but may also cause flooding and waterlogging.
• Impact on India is generally positive, although excess rainfall can result in localized challenges.
• Infrastructure planning and flood management become important during La Niña periods to prevent damage from heavy rainfall.
• Despite the positive influence on the monsoon, other regions worldwide may experience adverse effects such as droughts and hurricanes.