Alaska experiences dramatic changes in daylight hours based on the time of year. This is due to its high latitude location and the tilt of the Earth’s axis. During the winter months, parts of Alaska have 24 hours of darkness per day, while in the summer months, there are areas with 24 hours of daylight per day.
When is it dark in Alaska?
The further north you go in Alaska, the more extreme the changes in daylight hours become. In Barrow, Alaska, which is the northernmost town in the United States, there is a period of about 65 days centered around the winter solstice when there is complete darkness. Not a sliver of sunlight reaches Barrow from about November 18 to January 23. This period of 24 hour darkness is referred to as the “polar night.”
Further south in Alaska, the period of complete darkness is shorter. In Fairbanks, which is in Alaska’s interior, there are about 51 days of complete darkness from around November 26 to January 16. Coastal cities in southern Alaska like Juneau and Ketchikan do not experience a period of complete 24 hour darkness, but they still have very short days in the winter. Juneau’s shortest day has about 6 hours of daylight while Ketchikan’s has about 7 hours of daylight.
Key Facts About Darkness in Alaska
- Barrow – About 65 days of complete darkness from November to January
- Fairbanks – About 51 days of complete darkness from late November to mid January
- Southern coastal cities like Juneau and Ketchikan have between 6-7 hours of daylight on the winter solstice
What causes the extreme darkness in the winter?
There are two main factors that contribute to the extended periods of darkness during the Alaskan winter:
- Alaska’s high latitude location – It is located between 55° – 71° North Latitude, very close to the Arctic Circle (66.5° North)
- The tilt of the Earth’s axis – This tilt of about 23.5 degrees means the northern hemisphere is tilted away from the Sun during winter months
So the combination of being so far north and the orientation of the Earth results in very short days and long nights, with periods of 24 hour darkness north of the Arctic Circle.
Other High Latitude Locations with Extreme Darkness
Some other high latitude northern locations also experience an extended polar night each winter:
- Northern tip of Norway
- Northern Sweden and Finland
- Parts of Siberia, Russia
- Northern Canada
Chart of darkness in Alaskan cities
| City | Smallest number of daylight hours | Complete darkness |
|---|---|---|
| Barrow | 0 | Nov 18 – Jan 23 (65 days) |
| Fairbanks | 0 | Nov 26 – Jan 16 (51 days) |
| Anchorage | 5 | None |
| Juneau | 6 | None |
| Ketchikan | 7 | None |
This table demonstrates how the period of complete darkness becomes longer the further north you go in Alaska. Arctic cities like Barrow and Fairbanks have periods in the winter when the sun does not rise at all for over 50 days. More southern cities like Juneau and Ketchikan still get a few hours of filtered daylight even on the winter solstice.
What causes the extreme darkness in the winter?
There are two main factors that contribute to the extended periods of darkness during the Alaskan winter:
- Alaska’s high latitude location – It is located between 55° – 71° North Latitude, very close to the Arctic Circle (66.5° North)
- The tilt of the Earth’s axis – This tilt of about 23.5 degrees means the northern hemisphere is tilted away from the Sun during winter months
So the combination of being so far north and the orientation of the Earth results in very short days and long nights, with periods of 24 hour darkness north of the Arctic Circle.
Other High Latitude Locations with Extreme Darkness
Some other high latitude northern locations also experience an extended polar night each winter:
- Northern tip of Norway
- Northern Sweden and Finland
- Parts of Siberia, Russia
- Northern Canada
What is life like during the polar night?
The extended periods of darkness during the polar night have a significant impact on everyday life in Alaska. Here are some of the effects:
- Increased depression and fatigue – Lack of natural sunlight exposure can disrupt circadian rhythms and neurotransmitter activity, contributing to higher rates of seasonal affective disorder.
- School days are darker – Some schools in arctic Alaska even close for a few weeks around the winter solstice due to the darkness and cold.
- Difficulty navigating outdoors – It can be hard to get around safely when it is dark all day and icy. Reflective gear is essential.
- Warmer clothing needed – With little to no direct sunlight, temperatures drop dramatically during the polar night. Thicker coats, hats, and gloves are a must.
- Different activity routines – Outdoor activities need to shift to accommodate the darkness through things like lights, reflectors, and scheduling adjustments.
- Increased utility bills – More artificial lighting and heating is required, which increases electricity and fuel consumption.
The human population that persists in the far northern regions of Alaska during the winter must make significant adaptations to deal with the challenging conditions imposed by months of perpetual darkness.
Coping Strategies
People use various strategies to help cope with the long polar night in arctic Alaska:
- Using full spectrum, high intensity lamps to simulate daylight indoors
- Exercising regularly to increase serotonin, endorphins, and vitamin D
- Taking supplements such as vitamin D3 and omega-3s
- Engaging in social activities and community events
- Enjoying the unique beauty of the polar night through activities like aurora viewing
- Taking a sunny vacation to break up the long winter
- Practicing mindfulness and maintaining a healthy sleep routine
How many hours of daylight occur during the summer?
Just as Alaska experiences extended periods of complete darkness in the winter, it also experiences extremely long days during the summer months. This occurs for a couple main reasons:
- Alaska’s high latitude – The entire state is north of 54° North, very close to the Arctic Circle (66.5° North)
- Earth’s tilt – The northern hemisphere tilts towards the Sun in summer, bringing more direct sunlight to high latitudes
So even as far south as Anchorage, there are over 19 hours of daylight on the summer solstice. And north of the Arctic Circle there are periods where the sun does not fully set for over 50 days – referred to as the “midnight sun.”
Hours of Daylight in Alaskan Cities
| City | Longest Day (Hours of Daylight) | Complete Midnight Sun |
|---|---|---|
| Barrow | 24 | May 10 – Aug 2 (84 days) |
| Fairbanks | 21.5 | None |
| Anchorage | 19 | None |
| Juneau | 17.5 | None |
| Ketchikan | 16.5 | None |
During the summer solstice, cities in southern Alaska like Anchorage, Juneau, and Ketchikan experience 17-19 hours of daylight. But up near the Arctic Circle in Barrow, there is a period of about 84 days centered on the summer solstice when the sun does not fully set and it is daylight the entire time.
Impact of endless daylight in the summer
The long days of neverending daylight in the Arctic summer have some interesting effects, including:
- Messed up sleep schedules – It’s hard for the body to know when to sleep when it never gets dark outside.
- Eye masks are common – Used for blocking out the constant daylight to help with sleeping.
- Increased outdoor activities – Endless daylight means more opportunities for fishing, hiking, camping, etc.
- Later sunsets and sunrises – In Barrow the sun just spins low on the horizon, not fully rising or setting during the midnight sun.
- Warmer temperatures – The round-the-clock sunlight warms the northern lands and melts sea ice.
- Disrupted animal behaviors – Migration and mating patterns can be altered by the unusual photoperiod.
People living under the midnight sun need to adjust their routines and behaviors to adapt to the unusual circumstance of nonstop daylight. Room darkening curtains and eye masks help modulate exposure for improved sleep.
Coping Strategies
People use various strategies to help adjust to the endless daylight during the arctic summer:
- Using blackout curtains and eye masks to regulate light exposure in bedrooms
- Taking melatonin supplements to help reset the body’s circadian clock
- Avoiding caffeine and electronics use before bedtime
- Exercising in the “morning” to help feel tired at “night”
- Establishing regular meal and sleep schedules as best as possible
- Using earplugs and white noise machines to reduce disturbances
- Taking short naps as needed to relieve fatigue from lack of normal sleep
How do Alaska native peoples adapt to the extreme seasonal daylight variation?
Alaska is home to a diverse range of indigenous peoples including Inuit, Yupik, and Aleut peoples. These native groups have adapted to the extreme seasonal variations in daylight at high latitudes over thousands of years:
- Spending summers fishing, hunting, and gathering food to store for the winter months
- Building underground homes called “barabaras” that help regulate temperature
- Wearing fur and skins to survive harsh arctic winters
- Following the migration patterns of animals in the different seasons
- Sharing community resources to help each other through hardships
- Consuming fatty fish and whale blubber to get vitamin D with little sunlight
- Using fire to heat and light dwellings during periods of darkness
- Gathering in community houses for social activities, dancing, and storytelling
- Passing down knowledge of survival from elders to younger generations
Alaska natives developed cultural traditions, stories, diets, tools, clothing and modes of shelter uniquely shaped by the extreme contrasts of endless daylight and darkness throughout the year in the Arctic region they have called home for over 12,000 years.
Impact of Modern Technology
The introduction of modern technologies has helped Alaska natives adapt in new ways:
- Snowmobiles and ATVs allow better access and mobility in the tundra environment
- Rifles make hunting larger game easier
- Outboard motors greatly improve fishing abilities
- Aircraft provide increased transportation options year-round
- Communication networks keep remote villages connected
- Utility systems and fuel oil provide lighting, heating, and power
- Greenhouses allow local food production to be extended
But these advances have costs as well, disrupting traditional lifestyles and increasing dependency on expensive equipment and fuel. Many native communities are seeking ways to responsibly integrate modern tech while preserving their cultural heritage and resilience developed over millennia of Arctic living.
Conclusion
Alaska’s high latitude location close to the Arctic results in dramatic seasonal variation in daylight. For several months around winter solstice, northern cities have no daylight at all for periods of 50-65 days – known as the “polar night”. Conversely, around the summer solstice, areas north of the Arctic Circle experience a “midnight sun” with non-stop daylight for weeks.
These endless stretches of darkness or daylight have profound impacts on everything from mood, sleep, activity patterns, and temperature. Over thousands of years, Alaska native peoples have developed unique cultural practices and lifestyles shaped by adapting to this extreme seasonal contrast. With creative application of technology and community support, modern residents persist and thrive despite the formidable challenges posed by Alaska’s long, dark winters.