A sunset over Virginia mountains

Spectacular Sunrises and Sunsets: The Science Behind It

Hi friends! Woweewow. It’s December and I am sharing just my FOURTH blog post of the year! It has been a big ole year, highlights of which include starting my very own photography business, traveling to Hawaii and the San Juan Islands, returning to the office 3 days a week for work, several conference presentations, weekend meet-ups with the fam, fall backpacking trips, and GETTING ENGAGED to my sweet fiancée Nick!

This blog post was planned for peak-summer when we had all of the daylight hours to our hearts’ content – – and then life happened! But as a big believer in ‘better late than never,’ I’m choosing to share with y’all now! The coolest part of this blog post is that my dear friend Hannah wrote this. Over the past couple of years, I’ve watched Hannah go through the most epic transformation. In grad school, Hannah was the friend that didn’t “do” hikes and thought that I was out of my mind with all of my outdoor adventures. She would regularly call me her “cool friend Hayley,” perhaps subconsciously believing that cool things were meant for other people and not herself. In the past couple of years, she has now gone on to do some crazy hiking and backpacking challenges, took her first international trip, runs a super trendy PoshMark store, is becoming a climber, and even learned to skateboard! So to my cool friend Hannah: I am so proud of you and am the most excited for the outdoor adventures that await us!! Now, listen to Hannah as she tells us how to plan to enjoy the most epic moments of the sun doin’ it’s thing!


Hey friends, I’m Hannah! I’ve called Roanoke, Virginia home for the last 3 years and have acquired a great love for the outdoors and seeing the majesty of God though our world. Drives on the Blue Ridge Parkway and sunrise/sunset hikes are my love languages. If you’re like me, you’ve wondered how to predict the perfect sunset and what makes some sunrises better than others. I’m no meteorologist, but I’ve done some research and have created for you a basic guide on the science behind sunrises and sunsets and how to make the most of them! Most of the photos shown in this article are my own. The ones that I’ve taken all have no edits or filters added.

Here’s a brief lesson on sunset colors: Sunlight actually contains all the colors of the rainbow. When a ray of sunlight hits a molecule in the sky, a process called “scattering” occurs. The sunlight’s ray is reflected off in a bunch of different directions, and this happens millions of times before reaching your eyeball. The sunlight has less distance to travel through the atmosphere before reaching our eyes during the daytime, and the oxygen and nitrogen particles in our atmosphere do an excellent job of scattering blue and violet rays (the shortest rays), which is why we see blue sky in the daytime. 

For sunrise and sunset, the sunlight has to pass through more of the atmosphere. Fun fact: the same ray of sunlight is hitting the west coast and east coast at the same time. Essentially, the east gets the west’s leftover light – which means the east gets more of the colors with the longer wavelengths; the yellows, oranges, and reds. The diagram below shows the sunlight’s path across America.

Diagram by Stephen F. Corfidi

Now for my tips on finding the best sunrises and sunsets!

1. Watch the time – and plan to arrive early/stay after.

When looking at the time of sunrise/sunset, that is when the sun first peeks over the horizon (sunrise) or is completely gone (sunset). That’s the time most people go to look at a sunrise/sunset – if you do that, you’ll miss the best parts! For sunrise, plan to arrive 30 minutes early to see the best colors. For sunset, plan to stay around 30 minutes afterwards. 

2. Be aware of the direction the sun will rise/set.

The sun rises in the east and sets in the west…only two days per year, on the spring and fall equinoxes! This photo shows the sun rising in the same landscape during the different times of the year – notice how much it shifts!

Photo by Irv Bromberg

For those of you who want the 10,000 foot view, here’s what the sun’s path (blue) looks like at the different times of year. Notice how the path on the Winter Solstice is shorter than the rest – the shortest day of the year. The summer solstice has the longest path – the longest day of the year! Look at where the sun paths hit the green circle (symbolizing the ground). On the Winter Solstice, the sun rises in the southeast and sets in the southwest. On the equinoxes (March & September), the sun rises exactly east and sets exactly west. On the summer solstice, the sun will rise in the northeast and set in the northwest. 

Diagram from the University of Massachusetts 

The sun path will flow back and forth over the course of the year – basically, as it gets closer and closer to the summer solstice, the sun will rise/set more and more northeast/northwest, and then after the summer solstice, it will slowly but surely start to move back towards rising/setting perfectly in the east/west as you get closer and closer to the equinoxes. When picking an observation spot, be sure to know what direction it faces and how that relates to the time of year! 

3. Check for air quality.

Technically, every sunrise & sunset all have amazing colors. But as the light reflects in the sky, particles in the air (natural chemicals produced by trees, pollution, dust, etc.) can “block” the sunlight from reaching your eyes and therefore prevent you from seeing all the colors.

Two big myths: Pollution and humidity create the beautiful colors. In actuality, the cleaner and drier the air, the prettier the colors. 

Low-lying pollution, like you might see in Los Angeles, New York, etc., will actually make the sunrises/sunsets murky and hazy looking – more particles to “block” the sunlight. The “pollution” that can lead to beautiful colors is the high-atmospheric pollution, such as ash from a volcano or smoke from a wildfire. Note that you actually need to be kinda far away from these places to get the good colors; being closeby a wildfire won’t be great because a lot of the smoke is still low in the atmosphere. But when the particles are higher in the air, there’s more for the sunlight to bounce off of, allowing us to see more of the longer wavelengths (oranges and reds) at sunrise and sunset. Notice in the photo below how pollution mutes the colors of the sunrise: 

Photo by Sam Wermut 

Humidity can dull the colors of a sunset because the water droplets in the sky like to stick to those lower-lying particles that “block” the sunlight, creating more of an “obstacle” for us. Those muggy summer days usually won’t have fantastic sunsets since the heat/humidity traps a lot of the particles in the lower part of the atmosphere. However, you may be in for a great sunset after a big rainstorm – assuming the clouds blow off and clear up (see tip #4). This isn’t because of the humidity left behind, but because the air is cleaner from the rain. 

An easy way to check the air quality and humidity in your area is on the weather app. The lower these two numbers, the more likely you are to have some great colors. 

4. Know your clouds.

Okay, last science lesson…clouds serve as a great canvas for reflecting colors of the sunset, but not all clouds are good for this. Low-lying clouds actually will hinder your views; they will literally block the horizon and prevent you from seeing the various colors in a sunrise/sunset. High atmospheric clouds are what you want – cirrus, cirroculumulus, and cirrostratus clouds won’t be in the sun’s way, so they’ll just reflect the colors that are down along the horizon in our line of vision. Here’s a reminder of all those different types of clouds that you learned about in elementary school, and a couple of my photos to demonstrate:

These high-atmospheric clouds take on the colors of the sunset, enhancing the sky.

Notice how these low-lying clouds block a good section of the horizon, preventing us from being able to see the full colors of the sunrise.

5. Location, location, location.

In my opinion, sunrises and sunsets just look better by water and/or mountains. If you can’t be by one of the two or both, find a field or an area free from big obstructions, and increase your altitude – park at the top of a hill, sit on a roof, climb a water tower (if anyone asks, I wasn’t the one who told you to do that…).

One of my favorite sunrise/sunset spots is Sharp Top Mountain in Bedford, VA. It offers 360 degree views! 

6. Turn around.

When watching, it’s tempting to focus on where the sun is. If you’re in an open area or are able to turn around to see the sky opposite of the sun, there will often be lots of different colors that way too. I frequently see lots of pinks and purples when I turn around.

7. Bring a sweatshirt and a drink.

Especially in the summertime, I’ve found myself shivering as I watch the sun go down. Once that sun is gone, it’s actually a lot chillier than you think! The last thing you want is to be uncomfortable while trying to appreciate something beautiful. Bring a sweatshirt or blanket to snuggle up! At some point in history, people decided we should drink hot drinks for sunrises and cold ones for sunsets – it really adds to the experience, so definitely pack a thermos or a few beers!

8. Put your phone down.

I have almost no pictures of sunrises/sunsets because I try to keep my phone down – most of the time, the colors just keep getting better and better and I used to find myself constantly taking pictures. By the end of it, I had lots of photos, but I was so caught up in taking them that I missed the beauty. Also, none of the photos did the sunset justice (I honestly feel like that’s how it’s supposed to be, though). 

Now..

I have two challenges for you: take just one photo and take a few moments to express some things you’re thankful for. It’s great if you’re with loved ones and can tell them one thing you love about them. 

Now get out there and chase those sunsets!

Citations:

Corfidi, Stephen F. The Colors of Sunset and Twilight, NOAA/NWS Storm Prediction Center, Sept. 2014, www.spc.noaa.gov/publications/corfidi/sunset/.   

Fiegl, Amanda. “Red Sky at Night: The Science of Sunsets.” National Geographic, National Geographic, 10 Feb. 2021, www.nationalgeographic.com/science/article/131027-sunset-sky-change-color-red-clouds-science.   

Resnick, Brian. “Why Sunsets Are Better in the Winter.” Vox, 22 Nov. 2019, www.vox.com/science-and-health/2019/11/22/20970563/sunset-science-explained-rayleigh-scattering.  

Thompson, Daphne. “Are the Wildfires Out West Creating More Colorful Sunsets?” Weather Ops, 10 Aug. 2018, https://blog.weatherops.com/are-the-wildfires-out-west-creating-more-colorful-sunsets#:~:text=After%20a%20massive%20volcanic%20eruption,the%20best%20sunrises%20and%20sunsets 

University of Wisconsin – Madison. “What Determines Sky’s Colors At Sunrise And Sunset?.” ScienceDaily. ScienceDaily, 15 November 2007. <www.sciencedaily.com/releases/2007/11/071108135522.htm>. 

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s