Disclaimer: Copyright infringement not intended.

Context

• In February 2025, global sea ice cover reached a new record low, with the combined extent of Arctic & Antarctic sea ice falling to 15.76 million sq km.
• This is a big reduction from the previous record low of 15.93 million sq km. this previous low was recorded in In early 2023.

What is Sea Ice?

• Sea ice means ice that forms & floats on the surface of the sea. It is mainly found in the Arctic & Antarctic regions.
• These Different from glaciers because ice sheets, & icebergs, sea ice forms in the ocean. And it expands in winter & melts in the summer. And some remain all over year.
• This sea ice is an important indicator of climate health because it directly influences the planet's energy balance & climate.

Key Observations

1. Current Sea Ice Extent:
   • Arctic Sea Ice is currently at lowest recorded.
   • Antarctic Sea Ice is also very close to a new low. A satellite record from the late 1970s is showing a trend of decreasing sea ice.
   • From 1979 to the present, Around 77,800 sq km of sea ice was lost annually. As per National Snow and Ice Data Center (NSIDC).
2. Historical Trends:
   • Between 1981 and 2010, the Arctic sea ice extent decreased by 2% / decade during September
   • September is the month when it reaches its minimum extent.
   • Antarctic Sea Ice: From 2014-2017, Antarctica lost 2 million sq km of sea ice. This is  mostly 4 times the size of Spain.
   • In 2023, Antarctic sea ice was more than 2 million sq km below the maximum extent, which is 10 times the size of the UK.

Reasons Behind the Dip:

1. Warm Air and Oceans:
   • Both the Arctic & Antarctic regions are facing warmer than normal temperatures. And it is contributing to sea ice melt.
   • Antarctic sea ice: Important factors covers the presence of ice breaking winds, warm air & ocean temperatures near the end of the Southern Hemisphere summer from December to February.
   • Arctic sea ice: In Arctic, unusually warm ocean temperatures delay the freezing in Hudson Bay. Hudson bay is a saltwater body in northeastern Canada.
   • And storms also disrupt ice formation near the Barents & Bering seas.
   • Additionally, Arctic sea ice is becoming thinner & more fragile. And this is making it more vulnerable to environmental stresses such as storms & warmer temperatures.
2. Ocean and Atmospheric Patterns:
   • The ongoing warming of the oceans & atmosphere in both polar regions is making conditions that always disrupt the normal formation & stability of sea ice.

Implications of Reduced Sea Ice Cover

• Sea ice reflects sunlight. When it melts, then darker sea water absorbs more heat. And it causes warming.
• This creates a positive feedback loop, where less ice radiates more heat. And it causes more ice to melt.
• Melting ice also increases the amount of freshwater. And then it reduces salinity & density. This can hinder circulation.
• And This can affect global weather, marine ecosystems, & ice shelf stability.
• Loss of sea ice causes problems to marine life, including polar bears, penguins, & seals. these depend on the ice for breeding & feeding.
• The polar regions are also warming faster than other regions. This is known as  polar amplification. And this is affecting global weather patterns, sea levels, & biodiversity.

About Arctic and Antarctic regions:

Source: Indianexpress