Most of us know about the four seasons and the special relationships that different places can have with them. There are dry seasons, seasons that bring great storms, and times when amazing blooms and colors transform the land. You’ve seen it in autumnal leaves, avenues of cherry blossoms, fields of fruit, and grasses that grow ten feet fall! Seasons were our clock before we had a better way to count the time- and here in Iceland that is truer than most. 

If you’ve had the chance to visit Iceland, or any country in proximity to the poles, you may have already experienced the extreme patterns of light that I’m referencing. Tales of the ethereal “Midnight Sun”, or endless days of darkness that see no light. The closer to either pole you get, the more severe this pattern becomes. 

Because of the tilt in the Earth’s axis, the polar regions of the Earth find themselves much closer to the sun in summer, and much further away during winter. As you move closer to the equator, many countries further down feel the echoes of these shifts in light as well. Some, even further north than Iceland, feel it even more. 

You can see what the annual sun graph of Reykjavik looks like here. It’s a great way to get an idea of what the light will be like when you visit. Try it for your home, or a city far away from you. It’s amazing to see how differently we experience the world- even at the same time. 

The Icelandic settlers of old had to balance their survival with this harsh cycle- and created a calendar to help them manage their livestock, their crops, and their morale. This old calendar still has bearing on society today, and its holidays are still beloved as reminders of the natural progression of this place, in a way that the modern global calendar sometimes is not. 

This calendar was based heavily around solstices and equinoxes of the year, and with its 12 months it splits the year into two halves. These halves were the summer/nattleysi, or lack of night, and the winter/skammdegi days, or short days. All of these were checkpoints in the arc of time, and were visible and even ways to mark its passage in a place where it often felt as if there were only two seasons to measure. 

It was a difficult life for the settlers, and surviving the winter was a cause for great celebration. You can tell when the local populace felt the breaking of winter at the end of April- because that is traditionally when Iceland marks the first day of summer, or sumardagurinn fyrsti. This is a national holiday, and it is celebrated on the first Thursday after April 18th. This is a day of festivals and merriment, even though it may not seem very summer-like in temperature or appearance. But for Icelanders, this day marks the end of the long dark, and the beginning of the lengthening of days.

At one time, it meant the increased likelihood of survival, and days where one could work, craft or read without the obstacle of losing the light.

We know a little bit now about Iceland’s age-old relationship with seasonal time, light cycles, and surviving the harsh winters. But where do the northern lights come into all of that? 

To give you the short version- the northern lights themselves can happen at any time. 

They happen so far above our planet in space, that temperature, season, and time don’t mean too much when it comes to their arrival and creation. The first thing to realize about the aurora, is that it is a function of space weather before all else- but seeing it does require a little bit of cooperation from our own Earth weather, as well. 

When an aurora is born, it is due to the sun releasing a solar storm into outer space. You can read more about that process here. We can track these storms to an extent because of the orbital patterns of the sun and the reappearance of sunspots, which more regularly release these strong systems. However, our ability to measure and predict space weather is still very much a developing science, and can be imperfect at times. 

Despite all of that, the sun is releasing this energy all the time. Depending on the solar cycle and factors facing the travel of solar storms, this activity can find its way to us at any time of year, in any season. This means that it’s entirely possible for solar activity to arrive in our atmosphere in the middle of summer, or during the brightest point of day. 

The difficulty here is actually with us. Auroral light is a visually delicate natural phenomenon, despite its volatile origins. To see it with the naked eye, we require darkness in order to pick up the low lumen light that it creates. 

(An additional difficulty here lies with us as a species, because of how we perceive color visually in dark places. Because we are not nocturnal, our eyes are not designed to process color as well at nighttime, and so it’s already challenging for us as creatures to look at this type of light.)

Which is where we circle all the way back around to our first point- and Iceland’s dramatic dark and light seasons. 

If the aurora arrives in the high point of summer when we experience only civil twilight, we wouldn’t be able to see it. It would technically be there, dancing and possibly displaying incredible colors- but we would only be able to see that from space at best. (And sometimes, NASA sends us a video of it!) 

The same situation happens for us during the daytime, even in the winter months. Even though we only have a few actual hours of daylight, we still require the solid darkness of night to bring forth the best canvas for auroral glow.

Can we start our hunt earlier in the midwinter? Definitely! We can start heading out as early as 7 or 8pm on some nights, a thing that would be rather difficult to do in the earlier days of the auroral season. But we do still require that deep darkness of nighttime. 

In Midsummer and Midwinter, we start to lose or gain minutes of sunlight. This means that once we hit Midsummer, we begin the ever-increasing trek to winter darkness. We don’t always notice this right away, but typically once we reach August, it becomes dark enough to witness the spectacle of northern lights.

For me, the earliest I have seen them was at the end of the first week of August. This is only the beginning though, and so I would likely wait until a bit later in the season (late September at the earliest), to plan a trip.

This darkness builds every day until mid-winter when we start to gain the sunlight back. This typically means that we can witness auroral light until the very beginning of April, though March is the popular cut-off. (Similar to August, April would be the very tail end of the possible season- and would be a risky time to book an aurora hunt.

Though, there are quite a few intrepid photographers that catch them that late in the year, with lots of practice, lots of experience, and a tiny bit of luck. It is, of course, Lady Aurora herself waving goodbye for the year- she loves a dramatic exit.)

Some materials do talk about the ‘daytime aurora’, and this is not an incorrect statement. There are many places further north than Iceland (like Svalbard for example), that have an even more extreme sun graph than we do. (Though you can visit Siglufjörður, where they celebrate the first day that they see direct sunlight again.)

Places like this may not actually see the sun at all for quite some time- and maintain the ability to see northern lights for a longer period of time because of that. In addition to the extended dark hours during the day- they are also closer to the pole. Proximity to the pole can mean that they catch more of those low-level auroras that don’t travel very far out.

So don’t fret! The truth of the matter is that you have a whole half of the year to hunt for auroras in Iceland, as our forebears might say. (And for the other half of the year, you have puffins, endless lupine fields, and all the sun you can handle!)

You know about the Midnight Sun, the space weather that makes auroras, and the half of the year when we finally get enough darkness to see them. But what about Earth weather?

Earth weather does not interact with the northern lights, because it exists in the troposphere layer of our lower atmosphere. This is where most of the clouds in our atmosphere are located. It is sometimes said that extreme weather (things like polar vortexes and massive storms) can occur as far up as the stratosphere, but this is not entirely accurate. The stratosphere is particularly dry, and lacks the moisture to regularly create clouds, like the more humid troposphere.

To give you an idea of scale, these layers of the atmosphere combined are nearly 50 kilometres above the Earth. And still, it’s not high enough for auroras. 

Auroral activity occurs in the ionosphere, a section of the atmosphere that overlaps the mesosphere and the thermosphere. This is an area of the atmosphere where a great deal of electrons and ionized atoms and molecules occur, thus housing a key part of the collision recipe that makes the visible aurora. 

This means that myths about temperature and storms don’t necessarily hold true, and they don’t inhibit aurora activity. They do however get in the way of our viewing path. 

Since we are watching from the Earth’s surface, anything that does happen in our weather system can get right in between us and the aurora. This means that sometimes the aurora forecast is great, and shows high solar activity and an incoming show- but if it’s cloudy, it’s as if someone pulled the curtains. The show goes on of course, but anyone under the cloud cover is missing it. 

This is why the aurora forecast usually comes in two halves. The space weather or solar activity half (where we use the 0-8 Kp scale), and the Earth weather, or cloud map. 

Much of what we are discerning before a night out hunting, is can we see the sky, where is it the clearest, is that clarity window moving due to wind- and if we can find a good spot to watch from, is there any solar activity? 

Iceland is known for its rowdy winter weather, and depending on where you are in the country, you may find yourself exposed to some interesting micro climates and storms. The good news is, is that if you have the ability to travel and move around, sometimes it’s just as simple as driving over to the next cloudless spot. (And not forgetting the snacks, of course. It’s definitely a process some nights.)

You know it all, now! (Who am I kidding, nailing down space weather is a learning journey that never ends. At least not in our lifetime!) 

Let’s do a onceover to make sure we’ve got our northern lights trip toolkit together.

First, we have to book a trip in the right half of the year. This means we’re headed to Iceland some time between September and March at best. (If you want to catch the tail end of August or the early start of April, you can try it, but it would not be a recommended time frame for northern lights.)

However, it is always good to remember that the northern lights are a natural phenomenon, so it is best to plan a trip first for the experience of visiting the place. Iceland is a wonder all on its own, and the northern lights are just one of its many gifts. 

Once you’ve booked your trip for the ‘aurora half’ of the year, you’ve got to remember all of the pieces that have to line up in order for a successful hunt. 

These are things like making sure you’re out at night (not at 3:00 pm, even if you could swear it feels like midnight- which it kind of does in December-), making sure you’re in a clear area or an area that will become cloudless or ‘cloud light’ by nighttime, and of course, having a small check on if there’s any solar activity that evening.

It also helps to make sure you’re not in an area of extreme light pollution. Iceland is not populated by huge cities, so we do fairly well on this front, and it doesn’t typically take long to get out of the city and into some real nighttime. However, if you find yourself city-bound at any point, try looking for a spot that takes you out of the direct light and gives you a bit of a break on the eyes. 

It’s good to remember that many of these things are variable and imperfect, so it is not always necessary to plan by extremes- unless there is very inclement weather or a safety concern. (Those types of alerts always come first. Can’t enjoy the lights if you’re frozen.)

What I mean by this, is that forecasts are infallible. Not because they are in any way bad, but because weather is a volatile force that occasionally evades even the best of us. 

This means that the cloud radar can be off or slow, and the Kp number may not be accurate. It is possible for forecasts to gauge the speed of a solar storm incorrectly, as there are many factors that can add to that figuring. It’ll probably be a few years before we nail down space weather, but I can guarantee that there are a lot of brilliant people working on it.

This can mean that some nights, an aurora can occur on a Kp 0 evening. It can also mean that an exceptional evening (like a fabled Kp 8!), can disappoint us. This can happen for many reasons- which sometimes remain unknown to us. Sometimes powerful activity reaches so far that we end up in the middle of it instead, similar to being in the eye of a storm.

Sometimes it’s because we didn’t move very much on our hunt, and so we were only viewing one slice of the sky. It can happen that people see an aurora in one place, but a few kilometers over, nothing! Northern lights are like snowflakes in this way, and no two occurrences are alike. Forecasts are a great tool to have in your kit, and it can be good to cross reference a few good ones.

Learning to decipher all of the different forecasting tools can be complex, but like many other information sources, being able to read a few different ones can sometimes give you a more comprehensive idea of what may be going on. 

Sometimes, it can be that an aurora did happen, but it was a visually weak occurrence, and you did not realize you were seeing it. If you have only seen photographs of northern lights, it can be hard to recognize a low level manifestation- as they are not quite as neon and extreme as a photograph can be.

Nighttime photography uses processes like slow shutter speeds, aperture, and ISO to perceive light in darkness, in ways that our eyes cannot. This does not mean that auroras cannot be bright, or that all photos are photoshopped- but it does mean that the average occurrence will most likely not match the once-in-a-lifetime shot that you saw on a postcard.

Sometimes all of the factors are completely lined up, but there’s a weather warning, and it just isn’t a great night to chance it. The weather conditions can get very serious here very quickly, and are not worth risking. 

All together, this sounds like a massive feat. The thing to take away is, that if you have a window of clarity in the sky, and you’re here in the magical half of the year that gives us this other kind of light, have a look. Once you know how much work it takes for the universe to produce one of these things, it feels miraculous that they happen at the frequency that they do. 

Know that you may have to keep an eye out for longer than you’d expect sometimes, and you may not always be successful. But as every local knows, it is always worth looking up. They often happen when you least expect them. (..And it can also be nice to have a few drinks and a hot pot to soak in. You know. Or a transparent Bubble to wrap up in. Just saying.)