What are temperature blankets? Activists reimagine knitting trend as climate change tapestry.

Social media users may notice an annual trend popping up on their feeds around late December and early January as people display colorfully knitted blankets, boasting about the 365 days of effort put into one craft. Although the pieces likely look very different, the tapestries are collectively known as temperature blankets, which are crocheted records of daily local temperatures throughout a year.

The trend has been around for years, according to social media posts and expert knitters, but 23-year-old Becky Wenzel said that it was a TikTok post in December 2020 that caught her attention and made her want to create a temperature blanket of her own for 2021.

On Jan. 1, 2022, Wenzel took to social media herself to show off her completed work, measuring 6.5 feet by 8 feet, to her followers. "I started knitting this blanket on Jan. 1 2021 and I knit a row every single day with a color that corresponded to the highest perceived temperature of that day," she explained in the video that has 3.4 million views. "Every single day for the entire year and I just finished it."

Wenzel went on to show the color chart that she had used to organize her yarn colors and the temperature ranges that they each corresponded to in order to represent 365 days in Long Island, New York. But others across the globe are also showing their own blankets representing different regional temperature variations.

Nathalie Bouffard, who lives in Gatineau, Québec, Canada, told Yahoo Life that she's been creating temperature blankets of her own since 2017 when she first discovered them on Pinterest. For her, it presented an exciting new challenge for an already established knitting and crocheting hobby.

"What mainly caught my attention was that while you select the colors to use and carefully match them to a temperature range, the weather is doing all the deciding on the order and frequency that each of them is used," she said. "I tend to be very organized and I like to plan things so letting go and just seeing how the weather would affect the look of the final project seemed like an interesting idea to me."

Both creators showcased the planning process that goes into making one of these tapestries, explaining that they used other people's blankets to determine what color patterns they'd use to make their project personal.

"Most of the blankets I had seen looked just alright, though they were nice in design and execution, the color arrangements weren't a wow factor, I'm not exactly sure why, but most of them felt old, bland or too crazy and mismatchy for my personal taste," Bouffard said. "Since I knew this would be a long project, I wanted to be sure I’d like the end result so I spent a lot of time playing with the colors and making sure each color went well with all the others."

For the co-founders of The Tempestry Project — a collaborative fiber art effort created to provide data representative of climate change — the colors used in a temperature blanket are less about personal preference and aesthetic than they are about tracking global climate trends.

"We started our project in 2017, sort of in a more political and educational context. You know, the temperature blanket idea had been around for a long time, but we wanted to turn it more into sort of a climate change data representation project for people all around the world to start using," Emily McNeil told Yahoo Life.

Co-founder Asy Connelly added, "People would just sort of pick whatever colors they had in their stash and assign them to various temperature ranges for their area. And it was all just very individual efforts. And you couldn't compare any two temperature blankets together," she said. "Our thinking was to take all of this effort that goes into these temperature blankets and pieces and create a framework so that they can be compared. And you would end up over time creating a global mosaic of all these works."

McNeil was running a Washington yarn shop at the time of the project's 2017 inception and exploring innovative ways to participate in a knitting exhibit that she had been invited to. Connelly, who has a background in data processing and an interest in climate change, suggested that creating climate data could be that idea.

"In the lead up to [presidential] inauguration in 2017, there were articles coming out in various publications about scientists and hackers getting together and downloading just tons of climate and environmental data from the federal government for fear that the incoming administration would disappear it," Connelly recalled. "We had joked one evening talking about this that we should be recording data in forms that are harder to delete, like cuneiform tablets or tapestries. And then that sort of was the spark that spawned all of this."

In the years since, The Tempestry Project has worked with various knitting communities to share data, yarn and guides that make for a uniform process that allows tapestries to be used for collective data. "You can look at ones from Alaska and know that they're using the same temperature and color increments as ones from Death Valley, California, or other parts of the world," McNeil explained.

But even as people continue to focus on individual projects outside of these data collecting efforts, McNeil and Connelly said that their group's initiative is still being supported.

"A tapestry takes 20 to 30 hours to craft," Connelly said. "So if I look at each piece as somebody spending that much time thinking about the climate and weather, whether it's one of our tempestries or individual efforts, it all helps."

"It connects people to the way that they're experiencing their environment. And that in itself is a really powerful conversation and experience to have," McNeil said.

Wenzel told Yahoo Life that while her 2021 blanket is sitting at the end of her bed, she has plans to preserve it in hopes that it continues to carry significance into the future — whether it is kept in her family or used for a larger purpose.

"I've been trying to think of a good way to write and preserve some kind of journal entry or letter to keep with the blanket about what 2021 was like for me, but I haven't figured that out yet," she said. "In the meantime, I just added a tag I bought off of Etsy that says 'Temperature Blanket 2021 - Made by Becky' because so many people commented I needed to add the year for when it becomes a family heirloom or gets submitted for climate research."

Bouffard agreed that regardless of the intention that each knitter has at the beginning of their project, the result is a keepsake of countless important memories.

"They can be an especially great way to remember a special year in your life such as a birth year for a new baby, a newly-dating or wedding year for a couple," she said. "It's a subtle way to work these special moments into your craft. And there's nothing the feeling of accomplishment that comes with completing a year-long project."

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