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Iceberg Blue

Short answer: Glacier ice forms as snow is buried and compressed over years, squeezing out air bubbles. Ice and water absorb a little more red light than blue, so over long paths through clear ice, red is removed and the light that comes back looks blue.

Snow and bubbly ice look white because countless surfaces scatter all colors before much is absorbed. So deep, dense, bubble-free ice in a glacier or iceberg looks the most blue. The footage shows a glacier front calving blue ice into the sea.

VideoWrite-up2 sources

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What should you know about Iceberg Blue?

Quick facts. Each one stands alone and has a stable ID you can cite.

  1. Ice absorbs slightly more red light than blue.

    DD-299-F01 · Write-up · Exhibit B (Red is absorbed)

  2. Bubbles make ice look white.

    DD-299-F02 · Write-up · Exhibit D (Why snow is white)

Video transcript: Iceberg Blue: Dense Glacier Ice Glows Blue

DID YOU KNOW? The deeper blue color of iceberg's ice further down is due to the way that light interacts with the ice. As light penetrates the ice, the ice absorbs more of the longer wavelengths reds and yellows, and scatters the shorter wavelengths the blues. This effect is enhanced in denser, older ice which has fewer air bubbles and impurities. The clearer purer ice deep within the iceberg absorbs more red light and reflects more blue light creating a richer deeper blue color! NOW YOU KNOW!

Burned-in captions, read frame by frame (see transcript.md) · 23.9s Reel ·

Video coming soonIceberg Blue · Instagram Reel
Iceberg Blue: Dense Glacier Ice Glows Blue Instagram Reel · · 23.9s

The write-up

Dense glacier ice glows blue. Ice absorbs red light, so thick, bubble-free ice looks blue.

  1. Exhibit A

    Compressed snow

    Glacier ice forms as buried snow is compressed and air is squeezed out.

  2. Exhibit B

    Red is absorbed

    Ice absorbs slightly more red light than blue.

  3. Exhibit C

    Long light paths

    Over long paths through clear ice, the remaining light looks blue.

  4. Exhibit D

    Why snow is white

    Bubbles and grain surfaces scatter all colors, so snow looks white.

  5. Exhibit E

    Deepest blue

    Dense, bubble-free ice looks the most blue.

Questions people ask about Iceberg Blue

How does glacier ice form?

Air bubbles are squeezed out.

Source: Write-up · Exhibit A (Compressed snow) · Wikipedia: Blue ice (glacial)

Which light does ice absorb more?

The difference is small but adds up.

Source: Write-up · Exhibit B (Red is absorbed) · Wikipedia: Blue ice (glacial); Wikipedia: Color of water

Why does thick clear ice look blue?

Blue light remains.

Source: Write-up · Exhibit C (Long light paths) · Wikipedia: Blue ice (glacial)

Why is snow white?

Little light is absorbed.

Source: Write-up · Exhibit D (Why snow is white) · Wikipedia: Blue ice (glacial)

Which ice looks the most blue?

Light travels farther through it.

Source: Write-up · Exhibit E (Deepest blue) · Wikipedia: Blue ice (glacial)

Test Your Knowledge

All quizzes →

5 questions, all from this case file. Answers are revealed instantly.

  1. How does glacier ice form?

    1. Snow is buried and compressed
    2. Seawater freezes
    3. Rain freezes on contact
    4. Hail piles up
    Show the answer

    Answer: A. Snow is buried and compressed Air bubbles are squeezed out. Source: Write-up · Exhibit A (Compressed snow) · Wikipedia: Blue ice (glacial)

  2. Which light does ice absorb more?

    1. Red
    2. Blue
    3. Green only
    4. None
    Show the answer

    Answer: A. Red The difference is small but adds up. Source: Write-up · Exhibit B (Red is absorbed) · Wikipedia: Blue ice (glacial); Wikipedia: Color of water

  3. Why does thick clear ice look blue?

    1. Red is removed along long paths
    2. It contains dye
    3. It reflects the sky
    4. Algae live in it
    Show the answer

    Answer: A. Red is removed along long paths Blue light remains. Source: Write-up · Exhibit C (Long light paths) · Wikipedia: Blue ice (glacial)

  4. Why is snow white?

    1. Many surfaces scatter all colors
    2. It's too cold
    3. It has salt
    4. It's thin
    Show the answer

    Answer: A. Many surfaces scatter all colors Little light is absorbed. Source: Write-up · Exhibit D (Why snow is white) · Wikipedia: Blue ice (glacial)

  5. Which ice looks the most blue?

    1. Dense, bubble-free ice
    2. Fresh snow
    3. Frost
    4. Bubbly ice
    Show the answer

    Answer: A. Dense, bubble-free ice Light travels farther through it. Source: Write-up · Exhibit E (Deepest blue) · Wikipedia: Blue ice (glacial)

Cite this case file

Easterling, Marcus. "Iceberg Blue." The Detail Department (DetailEnjoyer), case file DD-299, last updated Aug 14, 2024. https://detailenjoyer.com/case/iceberg-blue/

Permalink: https://detailenjoyer.com/case/iceberg-blue/ · Last updated

Markdown version

Cite a single fact by its ID, for example DD-299-F01 → https://detailenjoyer.com/case/iceberg-blue/#DD-299-F01

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