Increasing Marine Heatwaves in the Indian Ocean

Context: In the study led by climate scientists from Pune has traced an increasing trend in the marine heat wave events in the Indian Ocean Region, which they say could affect marine life along with the future monsoons and cyclones.

Key Findings

• They found that Marine heatwaves have increased by up to four-fold in the tropical Indian Ocean, aided by rapid warming in the Indian Ocean and strong El Niños. 
• These marine heatwaves impact the monsoon by reducing the rainfall over the central Indian subcontinent while enhancing it over the southern peninsula.

About Marine heatwaves

• It is a short period of abnormally high temperatures in a sea or ocean.
• They are caused by a variety of factors such as sea star wasting disease, toxic algal blooms, and mass mortality of benthic communities.
• It occurs when ocean temperatures are extremely warm for an extended period of time can have significant impacts on marine ecosystems and industries.?
• Marine heatwaves can occur in summer or winter, which can be defined based on differences with expected temperatures for the location and time of year.

Impact of Marine heatwaves

• EXTREME WEATHER: Higher water temperatures associated with MHWs can cause extreme weather events such as tropical storms and hurricanes, and disrupt the water cycle.

INCREASED OCEAN STRESSORS: Like Stratification; Acidification; Deoxygenation

• It can cause changes in ocean ecosystems, impacting marine biodiversity, human health, and economies.

BIODIVERSITY & HABITAT LOSS: Habitat compression; Food web disruption; Species migration and Mass mortalities.

• It can force many species that are reliant on cold-water ecosystems to move from their familiar habitat.

ECONOMIC LOSS: Increased mortality of economically important species.

• Decreases tourism: They have other profound socio-economic impacts for coastal communities.
• Example: Aquaculture requires water temperatures to remain suitable for farmed species, while fisheries rely on species that often relocate in response to changing environmental conditions.They have major impacts on marine life and human society.

Road Ahead

• There is need to pass legislation that would help curb carbon emissions. Advancing the tools that predict marine heatwaves and adopting methods that help in changing climate and its effects on oceans is need of the hour.