2021 Crafting Project: Precipitation Scarf

Several years ago, I can’t remember where, I read about people who were knitting or crocheting “temperature blankets” to illustrate the local effects of climate change by coding the yarn color of each row of the blanket to each day’s high temperature. I loved this colorful idea! Smithsonian Magazine and the New York Times covered the phenomenon early in 2020. A scientist used crochet to illustrate temperature data in a conference poster in 2017. (I love this so much!)

Here’s a screen grab of what comes up in an image search for “temperature blanket”. So colorful!

I’ve crocheted a little in years past (my mom taught me the simple single stitch), but I’m not much of a fiber artist, so I never considered doing one.

Well, social media happened again.

A friend posted about the new yearlong challenge she was taking on: a temperature blanket! And some others of her friends were also planning to give it a go. I commented that I didn’t think I’d have the patience for a blanket, but thought a scarf might be doable. “Join us!” she said, and tagged me in a post about her “data visualization crocheting quest.”

That color palette is so choice!

OK, challenge accepted!

But, instead of doing temperature, I decided I wanted to log each day’s precipitation.

Here in the semi-arid High Plains, we don’t get a lot of moisture – just 15 inches a year, on average. Agriculture is able to thrive here thanks to the storage and distribution of snowmelt from the mountains to the west. Rainfall is often an EVENT. We keep a close eye on precipitation here. I’ve taken on these habits myself, often recording in photographs the rain, snow, and hail that fall at my house and sharing them with the Cheyenne National Weather Service.

(If you’re curious about that last picture, it’s featured in this blog post.)

As long as I’m making these observations already, I might as well crochet them into a scarf, hey?

I figured I’d represent rainfall in shades of blue and snow in shades of purple. Red for hail or graupel. I don’t want there to be red/hail in my scarf, but I know there will be. There always is. *sigh* I’m ok with graupel, tho. (Graupel is officially my favorite meteorological term.) In this arid climate, most of my scarf will be “no precip” – I decided I’d like a charcoal gray. And maybe a blended yarn of blue and purple to represent mixed precipitation?

Before going in search of yarn, I needed to figure out what sort of scale to use. I looked up rain data for the April-July period (using Weather Underground’s by-month daily history) and sorted the non-zero days into likely blocks. The snow was more variable, so I looked at Oct-Apr for 2019 and 2020 on the Daily U.S. Snowfall and Snow Depth reports from NOAA to get a sense of where to draw the boundaries.

Here’s what I came up with, measurements to be taken daily at 7am:
RAIN < 0.1″ = light blue
RAIN 0.1 – 0.5″ = medium blue
RAIN > 0.5″ = dark blue
SNOW < 1″ = light purple
SNOW 1-3″ = medium purple
SNOW > 3″ = dark purple

Then I went shopping . . . and came away a bit disappointed. The only yarn type that had the range of blues and purples I wanted didn’t have a charcoal gray in stock. I got a lighter gray with silver metallic threads instead. And no blue-purple blend, either. Oh well. That was probably too complicated anyway.

I still don’t know what I’m going to do on days with mixed precip, or on days with hail/graupel, since those will usually be accompanied by other precipitation. Crochet two rows? Weave a colored thread through the row? I’ll figure it out when I get there!

Here’s my “data visualization crocheting quest” colors and key:

The precipitation recorded at my house for January 1? Nada. The scarf begins in gray with silver sparkles.

I will perhaps updated this post when something exciting happens. (Like when I figure out what to do about those mixed precip days!)

Copyright 2021 by Katie Bradshaw, aside from the screen grabs of the temperature blanket images