The Earth is warming up, but this group of people is using ice as a “hard drive”.

The storage of information is one of the holy grails pursued by human technology (besides AGI).

From carving words on stone slabs to knotting ropes for record - keeping, from punch cards to magnetic tapes and hard drives, humans have tried all kinds of storage media, with both successes and failures.

But now, scholars from Beijing Institute of Technology have added a new player to this competition - a storage medium that has been right under our noses for thousands of years.

Ice. The ice that can be put in the fridge or added to drinks. That's it.

Of course, it's not about carving words on ice... but a more delicate method: encoding information by manipulating the tiny bubbles trapped during freezing.

This technology sounds a bit "cool" (pun intended), but think about it: offline, cold, and hard to be invaded - isn't this literally "cold storage"?

Nature's hard drive, cold and ancient

The Earth is warming up, yet someone wants to use ice as a hard drive. What a bold idea! However, the underlying principle is surprisingly elegant and has been proven effective by billions of years of cycles:

About 10% of the Earth's surface is covered by ice. The atmosphere circulates into the water bodies, and when water freezes, it traps the atmosphere in the form of "trapped bubbles". Ancient ice cores around the world have sealed the secrets of the ancient atmosphere, becoming natural time capsules. They are a treasure trove for scientists, restoring the appearance of the Earth billions of years ago and providing new insights into unsolved puzzles about the environment and evolution.

In other words, if the Earth is a computer, then ice is its "hard drive". The inescapable bubbles are countless data points.

Illustration: The ancient atmosphere is sealed in ice, and later humans use it to understand the prehistoric Earth

Knowing these things, the next time you go to a bar, you may have a different feeling: The bartender's pursuit of perfect transparent ice cubes is actually going against the laws of nature...

How to more precisely control the trapped bubbles in ice also troubled Song Mengjie, a professor at Beijing Institute of Technology and an expert in thermodynamics. He told me that when he was a special researcher at the University of Tokyo in 2018, he did a lot of research on micron - sized trapped bubbles and figured out the general idea of bubble control.

These discoveries took root in his mind like seeds and germinated new inspiration:

Since nature can use ice as a "hard drive", why can't we?

The principle of controlling bubbles is quite simple: When water freezes, it squeezes out the dissolved gas, forming trapped bubbles. If the cooling is too rapid, the bubbles are oval - shaped; a bit slower, needle - shaped bubbles appear; even slower, there may be no bubbles at all - skills that senior bartenders have already mastered.

Don't these bubble morphologies, corresponding to 1 and 0, dots or dashes, on and off, become a piece of data?

However, this discovery alone is not enough. If it's just a simple mapping of 1 and 0, a piece of ice may not be able to store a complete sentence. The team needs to improve the efficiency of encoding information and the storage density to make this discovery more practical.

The Beijing Institute of Technology team built a device. You can imagine it as a "2D printer" designed specifically for ice: A layer of water is sandwiched between transparent plastic sheets, and there is a cold plate below for precise temperature control. Through precise signal processing, a perfect temperature curve is designed for the cold plate.

By controlling the two variables of temperature and time, the team can stably and efficiently generate ordered bubbles. This is encoding, but it's more like creating a painting in ice.

The process of generating (encoding) bubbles

The decoding process is also simple and elegant, with a beauty that programmers can understand: Take a photo of the ice, convert it into a grayscale image, and let the computer vision algorithm handle the rest. The software reads information such as the particle size, morphology, quantity, and distribution of the bubbles and translates them into binary or Morse code.

Logical diagram of the encoding and decoding system

Encoding and decoding of the CN (China) and BJ (Beijing) fields using Morse code

Finally, humans have mastered the ability to communicate with ice. This sounds like a science - fiction novel, but reality is often more wonderful than imagination.

Imagine in a James Bond movie, Bond, who is used to dry martinis, gets a cocktail with a large square ice cube. The bartender's look tells him there's something in it. Bond uses his smart glasses to quickly read the bubbles in the ice, and the confidential information is transferred.

Of course, there is still a long way to go from the laboratory to Hollywood blockbusters.

Back to reality, Professor Song admitted that although the storage density of ice is not as high as that of traditional hard drives, it far exceeds the team's initial expectations: A 10 x 10 - centimeter ice sheet "can store about the information of 3 or 4 pages of paper."

Although it can't catch up with the SSD in a computer, at least for a literally "cold storage" solution, it's quite good. The improvement of storage density depends not on the research team but on the industry. This research focuses more on basic science rather than demonstrating application possibilities.

When asked about the difficulty of replicating this technology, Professor Song said that with commercially available conventional hardware, plus certain hands - on and computer skills, one can replicate it to a large extent, and it only costs "about 10,000 yuan".

Of course, this is just a rough and optimistic estimate. It doesn't mean that anyone can start producing hard drives at home with 10,000 yuan. Instead, it means that the technology behind this paper is not very difficult to replicate, and the threshold for popularization is low.

Illustration: The ice - making mechanism (B) and a simplified configuration diagram of the entire encoding and decoding system (A)

Cold technology, hot future

Ice is definitely not a good storage medium in all scenarios and cannot completely replace solid - state drives, which have great advantages in storage density and durability. However, this doesn't mean that exploring ice as a storage medium is a wild fantasy.

The challenges faced by traditional power - based storage technologies can be solved by ice.

Take the polar regions as an example. Traditional electronic devices not only face the challenge of low temperatures but also suffer from a lack of power. Uploading massive amounts of information via satellites is both expensive and unstable. In a white - covered world, a seemingly ordinary piece of ice may carry the important discoveries of an entire scientific research team.

Or, in the shadow of war, an electromagnetic pulse can easily cut off the lifeline of electronic devices. Ice storage consumes almost no energy. An ordinary ice cube may undertake the task of a server, cannot be detected by thermal imaging or tracked by electromagnetic radiation, and is both hidden and safe.

From another perspective, ice storage is a literally "cold storage" solution. Data that needs to be backed up and doesn't require frequent reading can be encoded into ice and stored at zero cost.

Especially in scenarios where power and hardware fail, or even in a doomsday scenario, ice storage can be very useful. Imagine that when extreme climate causes a huge tsunami, or humans stupidly start a final world war and push themselves to extinction... Ice storage can serve as the last "information ark" until the Earth's living environment recovers and society sprouts again.

Today, humans have extracted DNA from ice and successfully cloned Arctic wolves. When the moment of human survival or extinction arrives, why not turn to ice to preserve thousands of years of knowledge and cultural heritage - the proof of our existence?

Similarly, humans can use ice to convey information to future generations, like a drift bottle that will never break or be lost

Of course, from a mainstream perspective, these things are too far - fetched, too early, and too unimportant. So, let's change the perspective: The third and fourth technological revolutions represented by the Internet and AI have also brought excessive electronic waste to the Earth. Using ice to store data is exactly an embodiment of an opposite environmental philosophy:

The mountain of electronic waste in the near - future science - fiction movies is not far away. When the information in the ice is read and the ice is no longer needed, it can perfectly "degrade" into water or be directly used for other purposes, such as preservation, logistics, food, or even construction.

Speaking of construction - actually, information storage is not the only inspiration for Song Mengjie's team. When he was in Tokyo, he realized that the precise control of bubbles is not only applicable to ice but also to more solid or multi - phase materials.

A few days ago, we had a long talk in the office at Beijing Institute of Technology about the prospects of applying this technology to materials engineering science.

For example, whether due to the irreversible climate change or the explosion of aerospace technology, one day humans will become the "multi - planetary species" that Elon Musk mentioned. But when humans go to live on the Moon or Mars, they will find a lack of materials for large - scale construction. Many teams around the world are exploring the possibility of condensing lunar dust into solid materials through high - temperature and high - pressure methods for construction.

The principle of ice storage can also be applied here: Through the control of physical quantities such as temperature and pressure, bubbles (or foreign inclusions) can be precisely generated in various solid materials. The particle size, morphology, quantity, and distribution of these bubbles will also change the physical properties of the solid materials.

The "building blocks" cast by the European Space Agency using lunar dust, weighing 1.5 tons

Suppose a building needs bricks of different shapes. On Earth, we achieve this through mold casting, cutting, or material printing. This production method is difficult to apply on extraterrestrial planets. By controlling the bubbles in solid materials to "print" "bricks", a simple break by hand or a knock with a hammer can split them into the required shapes - this will greatly improve the efficiency of human construction in outer space and the quality of life.

(These possibilities are mentioned in the paper, but due to some objective rules of academic journals, this paper focuses on information storage.)

In the grand narrative of technological revolution, people are always looking for new breakthrough points - faster, smaller, stronger, smarter, etc. But sometimes, real innovation requires taking a step back and re - examining and utilizing things that we take for granted.

After studying this paper, I have a bold opinion: The most powerful technology is not necessarily the most complex and comprehensive but should be simple, elegant, and perfect in specific scenarios. It doesn't require rare - earth elements, doesn't produce electronic waste, and consumes almost no electricity. It only needs water, cold air, and some human wisdom.

Finally, I actually hope that you, who are reading this article, will never need to use ice - storage technology in your lifetime. But if humans still face the end, may the glaciers guard the hope of revival.

Text | Du Chen

This article is from the WeChat official account "ifanr" (ID: ifanr). The author discovers tomorrow's products. It is published by 36Kr with authorization.