We all know the fantastic water bubble bar when we go underwater, but, it doesn't really have that big of an impact. Would if there were more necessities to Minecraft? Today, a great update would lead to Minecraft being more challenging in the overworld, being more of an accomplishment to learning "survival" in general. Survival, obviously means, survival. Which means, temperatures are a big thing when it comes to Minecraft. For example, if you stand in fire, you'll obviously be caught on fire. I mean, it's logical, right?
Well, what would happen if you stand in a desert biome or taiga, or ice spikes biome? Nothing. This is why we need a change! When you enter a snowy biome, nothing will happen. But, if it snows, something will change. You'll be given a snowball bar on top of your food bar. You'll have ten snowballs, and every thirty seconds, one snowball will go away. You'll become colder. Basically, you have five minutes to stay there, if you don't find a way out. But, of course, to every problem, there's a solution. To avoid this, you can wear any armor given. This will completely get rid of the snowball bar and you can live happily ever after.
In a desert type biome, like the desert or mesa, nothing, also, happens. When it's sunny out and you enter one of the desert type biomes, you will be given a sun bar on top of your food bar if you're wearing armor. If you're not wearing armor, you're good to go. During night time, you must wear armor, and it works the same as the snow biome.
SNOW EDIT: In snow biomes, if you have some sort of tunnel or shelter, the bar will go away.
DESERT EDIT: As long as you're wearing armor underground in the desert, the bar will go away.