Let’s take everything we’ve learned above and use them in real life examples. Below we’ll look at two different clouds. We’ll take you through a thought process of how to properly classify them using techniques we’ve found that work well.
Example #1 – A Foggy, Dreary Morning
Above is a scene of a road where visibility is decreased from a low-hanging cloud which is practically touching the ground. This is a low-level cloud. If you remember, the four clouds that are found in the lowest level are cumulus, stratocumulus, stratus, and cumulonimbus. But this cloud has no detail. It’s a blanket cloud and a featureless layer, which is the perfect description of a stratus cloud.
But to further describe this stratus cloud, let’s further investigate to see what cloud species might be applied. Using this website as a field guide, stratus clouds can be associated with the fractus cloud species and nebulosus cloud species. The species ‘fractus’ describe clouds are ragged and broken up, where the species ‘nebulosus’ describe clouds are full of vapor and lack detail. While it’s not always necessary to apply a cloud species to an observation as we discussed above, in this example, the cloud lacks any kind of detail whatsoever. The species nebulosus would be applied here.
Next, let’s see if there are any cloud varieties that might be applied. Stratus clouds have three associated cloud varieties: opacus (latin for opaque), translucidus (latin for translucent), and undulatus (latin for undulating). In this example, it would appear that the cloud is thick enough to sufficiently block out the sun. The cloud isn’t translucent, and it’s not undulating. In this case, it’s appropriate to apply the opacus cloud variety.
Let’s see if there are any supplementary features that might be applied. Stratus clouds have two associated supplementary features: fluctus and praecipitatio. Fluctus describes clouds that have wave formations (also known as Kelvin-helmholtz instability) while praecipitatio is the latin term for precipitation. This cloud has neither, so there isn’t a need to apply a feature to it.
Finally, stratus clouds don’t have any associated accessory clouds, but they do have several other clouds associated with the cloud type: cataractagenitus (cloud created from waterfalls), homogenitus (cloud created from human activity), and silvagenitus (cloud created from forest evaporation). This cloud has neither of these three.
With that, we’ve arrived at our official classification: Stratus nebulosus opacus (St neb op).
In this example, we determined the cloud classification starting from the cloud type and working our way down through cloud species, varieties, features, and accessories taxonomy. In the next example, we’ll work backwards by identifying a cloud feature first instead of the cloud type.
Example #2 – A Warm, Muggy Afternoon
Above is a scene of a puffy cloud in the distance towering over some trees in the foreground. Notice something interesting about this cloud? The most distinct aspect of the cloud pictured is the smooth cap that sits overtop the tower. This cloud is recognized as a pileus cloud accessory.
Knowing what the accessory cloud is can be helpful in deciding the cloud type and ultimately classifying the cloud. Of the ten cloud types, only two cloud types are capable of creating a pileus accessory cloud: cumulus and cumulonimbus.
So as we decide between these two cloud types, consider the differences between cumulus and cumulonimbus clouds. If the cloud has precipitation or lightning, you would be observing a cumulonimbus cloud, or thunderstorm. In this case, the cloud is definitely growing, but there’s no sign of rain or lightning. In this case, we’ll ultimately decide the cloud is a cumulus cloud.
But the cloud is tall. It’s not your ordinary puffy cumulus cloud. It’s towering and seemingly on the rise. This is an ideal example of a cumulus congestus, which is the cloud species describing a cumulus cloud that’s taller than it is wide.
Before finalizing the official classification, double check to see if any other cloud varieties, features, or accessories can be applied. Cumulus clouds only have one variety, radiatus (sometimes known as cloud streets), which doesn’t apply in this case. Cumulus clouds also have five associated supplementary features: arcus, fluctus, praecipitatio, tuba, and virga. In observing this cloud, it has none of these, so there isn’t a need to apply a feature to its classification. Cumulus clouds also have three associated accessory clouds: pannus, pileus, and velum. We’ve already decided it has a pileus accessory, but pannus and velum accessories don’t apply.
With that, we’ve arrived at our official classification: Cumulus congestus pileus (Cu con pil).
In this example, we determined the cloud classification starting from identifying an accessory cloud and working backwards to determine its ultimate classification. As you become more familiar with cloud species, varieties, features, and accessories, the easier it is to identify clouds as a whole by not necessarily recognizing cloud types first.
This example should get you more excited for cloud species, varieties, features, and accessories. They’re pieces of the puzzle that help you put it all together.
Want more working examples? Check out our step-by-step cloud classification lessons and improve your skills!