This unusual activity in Antarctica could lead to hot summers in the southern hemisphere
Produced by: Tarun Mishra
Antarctic Polar Vortex Nears Historic Split
The polar vortex in Antarctica is on the brink of splitting into two, a rare event that hasn't occurred in over two decades, due to a sudden increase in stratospheric temperatures.
Potential Impact on Global Weather
If the vortex splits, it could lead to significant warming in Antarctica, while regions like Australia and South America could experience an unusually hot summer, affecting global weather patterns.
Nature of the Southern Polar Vortex
The southern polar vortex is a powerful swirl of winds that circulates clockwise, trapping a cold air current over Antarctica during the southern hemisphere's winter.
Current Unusual Instability
Typically, the vortex remains stable at this time of year, maintaining temperatures of around -80°C (-112°F) within its core. However, this year, the vortex has shown signs of instability.
Record Temperature Increase
In mid-July, wind speeds within the vortex dropped from 300 to 230 kilometres per hour, allowing cold air to descend and resulting in a record 20°C (36°F) temperature increase inside the vortex.
Shift in Polar Air and Potential Heatwave
The weakened vortex has been displaced from its usual position over the South Pole, causing cold polar air to move towards Australia, New Zealand, and South America, and warmer air to flow towards Antarctica, potentially triggering a heatwave.
Risk of Sudden Stratospheric Warming
A continued slowdown in wind speeds could cause the vortex to shift direction and swirl anticlockwise, leading to a phenomenon known as sudden stratospheric warming, which could further destabilize the vortex.
Long-Term Implications
According to experts, even minor disruptions to the vortex can escalate into extreme events, increasing the likelihood of a significant impact on global climate patterns if the vortex splits.