Antarctic research stations: Increase in ice

Antarctic research stations: Increase in ice

Question:- In recent years, scientists are posed with several problems such as increase in ice while reaching to Antarctic research stations to supply essentials to their respective stations. What could be the possible reasons for such anomalies? Explain.

- The sea ice in Antarctica is complex and counter-intuitive. Despite warming waters, some factors that are unique to the Antarctica region have contributed to an increase in sea ice. Antarctica has experienced high levels of sea ice in th past few years which has posed as a grave problem to the scientists who are unable to supply essentials to research stations.

- There has risen a need to develop accurate techniques in order to forecast the sea ice levels in the polar regions, saving millions of dollars in shipping. This can help arrange something like an ice breaker to carry supplies. more accurately forecast sea ice levels in the polar region, aiming to save millions of dollars in shipping costs.

Various reasons for the increase in sea levels:

1. Drop in ozone levels over Antarctica- The hole caused in the ozone above the south pole has caused a cooling in the stratosphere in turn bringing about a strengthening of cyclonic winds circling the Antarctica. The sea ice is pushed around by the wind creating areas of open water known as polynyas and an increase in this causes an increase in sea ice.

2. Changes in ocean circulation- The southern ocean has a layer of cold water near the surface and warm water layer beneath. The sea ice is melted with the warm water layer rising up to the surface. With the warming or air temperatures, amount of rain and snowfall also increases. With all this, the layers become more stratified and mix less with lesser heat transported upward from the deeper, warmer layer, melting less ice.

3. Absence of landmass- There is no landmass near the Antarctica ocean compared to the Arctic ocean which is surrounded by Denmark, Greenland and Russia, leading to unrestricted increase in sea ice.

4. El Nino effects- The southern oscillations are affected by the El Nino changing the prevalent pressure conditions, affecting wind directions near Antarctica which brings changes in sea ice.

5. Breaking away of icebergs- When icebergs break away, the place they get stuck at end up having more ice forming around them.

6. Reduction in heat- Decreasing temperature goes with increasing ice and the difference between bottoms of Pacific and Antarctica ocean causes heat reduction which causes ice formation.

7. Snow landing- Snow landing on thin ice may push the thin ice beneath water allowing cold ocean water to rise up through the ice flooding the snow. This leading to a unfrozen mixture which freezes in the cold atmosphere adding to the thickness of the ice. This thicker ice would be end up being more resilient to melting.

There hasn’t been one explanation yet for the phenomena where the key variables include atmospheric and oceanic conditions and the effects of an icy land surface, changing atmospheric chemistry, the ozone hole, months of darkness etc.

Facts and figures:

- Antarctica is home to Mount Erebus- the southern-most active volcano in the world.

- The Dry Valleys in Antarctica are the driest places on earth.

- Since the start of regular satellite observations in 1979, total Antarctic sea ice has increased by about 1% per decade.

- Globally from 1955 to 1995, oceans have been warming at 0.1°C per decade. In contrast, the Southern Ocean has been warming at 0.17°C per decade.