But there are also quite a few differences.
First off, the Carnival boots are meant for women. This is not to say men can’t buy them, but the fit will suit women more, for sure.
The Caribou is generally warmer and has a more robust and gripping sole. It is meant more for colder and more snowy conditions. That comes at a price though because the boot is significantly heavier (5 lb vs 1.5 lb).
The Carnival is more of a stylish boot as well. It looks similar in many ways to the Caribou, but the less harsh tread combined with the fluffier top makes it more fun and feminine. It also comes in a range of brighter colors (purple, light blue, pewter gray, and black) as opposed to the beige, gray, and black of the Caribou.
All in all, the Carnival is more of a stylish winter boot that will cope with some cold temperatures and snow but is not the workhorse that the Caribou was designed to be.
The Caribou is significantly heavier than the Carnival, which is partly because of the construction but also because of the more robust tread on the sole. It is a sturdier boot but is heavy to wear around all day.
The Caribou is also a lot higher on the calves at over 9 inches from the arch. The Carnival sits lower at 7.5 inches. So, it is easier to walk in, but protects you less from deep snow.
Unless you plan to be outside working in it, the Carnival might be a better option.
Again, the Caribou has a thicker felt lining in the boot designed to be warm down to -40. The Carnival is only rated to -25.
Keep in mind that these temperatures are only a rating and not always realistic (it depends on your socks if you sweat, your body temp, etc). However, they are a good indicator of how the warmth compares – the Caribou is warmer.
So, if you live in very cold areas in winter, the Caribou is a better bet.
The Caribou uses a leather upper while the Carnival has Nylon. I prefer natural materials myself, as they usually last longer. But it makes the boot a bit heavier I think.
Both these boots will serve you well, but you need to think about what you will use them for.
Price-wise they are quite similar so that does not play much of a role.
The Caribou works better in colder conditions and deeper snow. They are heavier though, so are not for long walks or hikes.
The Carnival is a more stylish boot intended for day-to-day use. It can handle the cold to a point, and the snow as well, but you won’t be shoveling 5 feet of snow in them. I would just use them if I lived in a cold place in winter that was not covered in a lot of snow.