I am currently doing laser physics research at SLAC National Accelerator Laboratory which is a laboratory owned by Stanford University. As I walk around Stanford, I have noticed a considerable drop in temperature. As I look up at the smoke-filled sky, all I can think of is how bad smoke is for light trying to travel in a straight line. And because I’m a laser physicist, I just think, if that were the environment my laser was in, I would be so upset. Dust reflects light, and that means my laser will have less energy because light is being ‘lost’. When working with lasers, in particular high-power lasers, our laboratories are considered to be clean rooms. Laser physicists normally wear clothing and gloves that prevents dust from getting into our laser systems. This way, our lasers can be as powerful as possible.
In a similar manner, the light from the Sun is trying to shine through the smoke-filled atmosphere in California but is being reflected off the smoke particles. This means that less light is reaching us on the surface of Earth, hence making it feel colder. This is why those of you in California might be bringing out the sweaters earlier than planned, I certainly have.
Something else that I noticed about the sky was that the sunsets appeared to be redder than usual. They are such beautiful sunsets, but in a way, it is sad to know that it is the smoke that is helping the sunsets appear more vibrant . Something known as the Tyndall effect is to blame. The Tyndall effect works for colloidal solutions like our smoke-filled atmosphere. Colloids are substances that have microparticles suspended in a fluid. When light is shone onto these substances, light is reflected. But if you consider the mathematics of the Tyndall effect you will see that the intensity or brightness of the scattered light is inversely proportional to the fourth power of the wavelength. So, in simple terms, this means that blue light is scattered more than red light. For us earthlings in California, we see more of the red light since most of the blue light is being scattered. This results in some stunning, rich-red sunsets.
A fun experiment to do at home to see the Tyndall effect in action is to pour some flour into a glass of water, mix it, and then shine some light on it. It should appear blue, since only the scattered light is being detected by our eyes. The scattered light is mostly made up of ‘bluer’ wavelengths, because blue light is scattered more than the red. Try it at home and let me know in the comments below.
These were some of my thoughts as I embark on my new journey here in California. For those in California, stay safe and hopefully the upcoming rain will help with the current situation.