Right now, it is easy for many of us to lose track of time and seasonal milestones. Indeed, with all the focus on the COVID-19 pandemic, I nearly missed one of my favorite seasonal milestones. It is the March Equinox! This seems like a particularly important time to take a moment and appreciate the cycles, rhythms and patterns of this planet we all live on. Today, find time to take note of how the increased daylight (in the northern hemisphere) or decreased daylight (in the southern hemisphere) affects plants, animals, weather, water cycles, and you.
The term equinox comes from Latin aequus (equal) and nox (night). It is a time when every place on earth receives about 12 hours of daylight and about 12 hours of darkness. Isn’t that cool? Actually, it is a little more than 12 hours of daylight. Find out why here!
Another really cool fact about the equinox is that on this day, the sun rises pretty much due east and sets due west, no matter where you are in the world! For observation based purposes, this is fairly accurate in the few days before and few days after the equinox too. This means that you can make their own maps of your neighborhood, backyard, park, or other favorite outdoor place and then use the sun to correctly orient your map to east, west, south, and north! Just observe where the sun rises, relative to key landmarks in the place you are mapping. That is east. Then observe where the sun sets, relative to key landmarks in the place you are mapping. That is west. South and north are easy to figure out from there. If you have windows in your home or apartment, you could even do this indoors and determine which walls are to the east and west.
If you want to get specific, March 20, 2020 marks the equinox in the Eastern Hemisphere and the night of March 19 is the equinox in much of the Western Hemisphere. The exact minute of the equinox is calculated based on when the tilt of the Earth shifts such that the sun “crosses” the celestial equator. An article from Earth and Sky explains this in more detail.
For the MOSAiC Expedition, located currently at about 87 Degrees North and 24 Degrees East, the March equinox is especially exciting. At the end of February, the Polarstern was still in the darkness of Polar Night (when the sun doesn’t rise above the horizon). By early March, they were experiencing twilight as the sun came close to the horizon. And on March 12, the sun officially rose above the horizon -- but it was hidden by thick clouds. The amount of daylight changes fast that far north! You can visit NOAA's sunrise and sunset calculator to find out when the sun is rising and setting for folks on the Polarstern. You can also use this tool to calculate sunrise and sunset in your location, or anywhere around the world!
In the northern hemisphere, the March equinox is called the spring or “vernal” equinox. And the southern hemisphere is currently celebrating their fall or “autumnal” equinox. For everywhere except the equator, the March equinox represents a shift between seasons. Increased sunlight in the northern hemisphere ushers in spring. Here in Washington state, spring is well underway. Leaves are sprouting on trees, early flowers are blooming, and a chorus of frogs can be heard in the ponds at night. In Homer, Alaska, snow is beginning to turn to slush. And farther north, a friend in Brevig Mission, Alaska told me that they are thoroughly enjoying 12 hours of daylight but they anticipate the sea ice and snow will stick around until late May. Though spring looks different at each of these places, the increase in daily light and warmth from the sun will -- sooner or later -- warm things up and power amazing growth of plants. And in the southern hemisphere, decreasing sunlight means that things will get colder and plant growth slows, or even comes to a stop.
Of course, spring (or fall) has different characteristics and timing across the world. What does the start of this season mean to you? What does it look, feel, sound, smell, or taste like where you live? Take a moment today, and in the coming days, to make note of signs of the changing seasons. You can use scientific descriptions, creative writing, photography, or other forms of art to gather these observations. Add what you've noticed in the comments here for others to learn from. You can also participate in a community-based monitoring project like Project Budburst! This is a really fantastic way to track when shrubs and trees leaf-out and flower around the United States.
For more activity ideas, check out my March Equinox edition of Arctic Connection: Linking Your Place to the MOSAiC Expedition. Some of the ideas for pinhole cameras and solargraphy could be especially interesting for adults and older students looking for fun projects right now.