As winter approaches, the northern hemisphere begins to prepare for snow. This week, Everyday Einstein explains the science behind snowfall, including snowflakes' shape and their implication towards the Earth's climate, and even shows us how to make our own snow.
Most snowflakes are no bigger than half an inch across, but if the conditions are just right (near-freezing temperatures, not a lot of wind, and an unstable atmosphere) snowflakes as large as 2 inches are possible.
What Does Snowfall Tell Us About Climate?
Individual weather events like snow storms or blizzards are linked to the overall climate of the planet, like the variations in patterns of temperature, humidity, and precipitation over long timescales. For example, snow cover helps regulate the Earth’s surface temperature, and snow melt replenishes the water supply in rivers and lakes. Thus warmer or shorter winters with less consistent snowfall and shrinking glaciers can be signs of a shrinking water supply to come.
Snow also has a very high albedo, which means it's very good at reflecting sunlight. Plants and dirt reflect only 10-30% of sunlight while snow can reflect up to 90% of the sun’s rays. This reflection of sunlight by snow cover helps maintain a cooler planet by sending that solar energy back out into space.
How Can I Make My Own Snow?
There are many recipes for making your own snow at a range of consistencies from powdery to slimy. For example, mixing equal amounts of cornstarch and baking soda into a bowl and then adding water slowly until you can form a snowball with your hands will allow for a snowball fight even in warmer weather. If your “snow” gets too runny, don’t worry—just add more cornstarch and baking powder. And for something even easier, you can simply buy instant snow powders. Just add water!
Until next time, this is Sabrina Stierwalt with Everyday Einstein’s Quick and Dirty Tips for helping you make sense of science. You can become a fan of Everyday Einstein on Facebook or follow me on Twitter, where I’m @QDTeinstein. If you have a question that you’d like to see on a future episode, send me an email at email@example.com.
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