Antarctic Winter: April–September Darkness and Extreme Cold

The Antarctic winter spans April through September. During this period:

• Continuous darkness: The sun does not rise above the horizon for weeks to months (depending on latitude), with midwinter (June solstice) bringing total darkness at the South Pole.
• Extreme cold: Average temperatures reach −50°C (−58°F); interior stations like Vostok and Amundsen-Scott have recorded below −80°C (−112°F).
• Isolation: No flights or ships operate; winter-over crews are completely cut off.
• Polar night effects: Psychological and physiological challenges (circadian disruption, vitamin D deficiency, "winter-over syndrome").

The summer (October–March) brings continuous daylight and relatively milder conditions (−20°C to −30°C coastal).