About

• An algal bloom is a rapid increase in the population of algae in a water body, often triggered by excess nutrients like nitrogen and phosphorus from agricultural runoff, wastewater, or pollution. 
  • Algae are simple, plant-like organisms that live in water. They can range from microscopic phytoplankton to large seaweeds like kelp.
• This nutrient enrichment process is known as eutrophication. 
• As algae grow excessively and eventually decompose, oxygen levels in the water decline, leading to hypoxia (dead zones). 
• This oxygen depletion results in the loss of marine life, reduced biodiversity, and disruption of the food chain.

Why in the News?

• A recent study observed that the severe algal bloom in an eutrophic lake escalates global warming.

How algal bloom escalates global warming?

• While phytoplankton sequester atmospheric CO2 and store it as organic carbon, most of it is eventually released back as CO2 and methane (CH4).
• Global warming has led to faster phytoplankton growth, which in turn releases more carbon dioxide and methane into the atmosphere. 
• This cycle reinforces itself, adding to climate change, with methane having a stronger warming effect than carbon dioxide.