Narration: Lauren Ward

Transcript:

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For the first time ever, scientists have created a 3D model of melting snowflake

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3D modelling coupled with new research about melting snowflake behavior

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serve as one of the first steps for creating better precipitation models

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used for weather forecasting and climate modeling in the future.

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We’ve actually known how to measure the size and shape of snow particles for a while

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But visualizing how a snowflake melts?

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That was only achieved in the last couple years

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Actually, by this guy – based at NASA's Jet Propulsion Laboratory in Pasadena, California

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probably one of the least snowy places in the United States

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Nobody else was really doing it and I kind of had a good hunch that it could be done

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In the past, researchers have adopted some pretty creative methods to catch snowflakes

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like using spider webs to net the delicate crystalline structures

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in order to watch their melt behavior

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But I don’t like the thought of writing this research proposal

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where I ask for money to breed spiders

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Understanding the microphysics of a melting snowflake has significant implications

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About 66% of rain starts as snow higher in the atmosphere

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And that layer of melting snow can, among other things

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affect weather patterns, block radio signals, and be a hazard to aircraft

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The hydrodynamics are actually particularly complex and completely different

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from the characteristics of rain or even snow that hasn’t started melting yet

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which is what prompted an entirely separate body of research

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The team created mathematical models that simulate a melting snowflake in nature

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allowing researchers to study its behavior in a controlled environment

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It turns out that the degree of riming has a major influence on the melting process

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Riming is the accumulation of super cold water vapor that freezes

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instantly when it comes in contact with a snowflake

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Heavily rimed snowflakes look more like hard, dense ice pellets

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while lightly rimed, “fluffy”, snowflakes often maintain their light, delicate crystals

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As you’ve probably already guessed, these fragile snowflakes melt pretty easily

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whereas hail-like snowflakes are less prone to breaking up during the melting process

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Now we have the techniques and we have the computer power

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to actually make simulations of these things

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