When you look up in the sky on a cloudy day whether you are an adult or a young child you can’t help but marvel at the beauty of the sky. Clouds can make some incredible patterns in the sky, produce some beautiful sunsets, and just add a nice background to a great day. While most people now understand exactly what clouds are they may not know a lot more about them. For example, do you know how much clouds weigh? Do they weigh anything? It may sound like a silly question but it is actually a very valid one. Let’s dive in and find out.
First of all, let’s be clear. Clouds do weigh something. While they would be tough to grab onto and hold they are made of matter and do have weight. How much, is a more difficult question. To understand the answer we need to understand a little more about clouds. All clouds were not created equal.
There are some clouds that are white, small, and fluffy. They appear on a bright day and contain very little water. These are called cumulus clouds and are probably the most common cloud that we all see. Then there are vast grey clouds that are light grey in color, suggests a light rain is coming and cover the entire sky. Finally, there are big storm clouds. These can be massive in size and very dark in color. They likely contain a lot of water. This is something that we all know from experience when we have been caught under one. So how much does each weigh?
The cumulus cloud
Clouds are basically made up of air and water. A cumulus cloud has approximately a quarter of a gram of water for every cubic meter of the cloud. A typical cumulus cloud could be 1km in length and 1km in height and maybe even 1km in width too. For simplicity’s sake at least, let’s imagine it is roughly a cube. If that was the case it would be 1 billion cubic meters in size. That means it would contain about 250,000,000 grams of water or 250 tonnes. Air also has a weight and this would make the cloud even heavier. Although this same air is what keeps the cloud in the sky so it is not exactly weighing it down. The air would weigh about 4,000 times more than the water and would mean that a cumulus cloud would weigh 1,000,250 tonnes. This means that clouds are extremely heavy but it also explains how they stay up in the air. The water is being held up by air.
The grey cloud that fills the sky
This cloud contains more rain and is far longer but it is not as tall. It contains roughly the same amount of water per cubic meter as the cumulus cloud but its greater size makes it far heavier. It could be 500km across the sky and would therefore weight about 50,000 times more than our fluffy cumulus. It would have around 10,000 tonnes of water alone
The storm cloud
Finally, we have those large black clouds that look so ominous on the horizon. They are much bigger than a cumulus cloud but not as big as that grey cloud that fills the full sky. A storm cloud may be 10km tall and again could be the same across so we are already looking at 10X of a cumulus cloud. In addition, it holds more water per cubic meter with about 2 grams per cubic meter. A storm cloud with the combined weight of water and air likely weighs 50 billion tonnes!
Clearly clouds are a lot heavier than we all think yet they are perfectly happy floating through the air as if they are light as a feather. Keep this in mind the next time you say you feel as light as a cloud, stick to the feather as your method of comparison.