I know it evaporates but shouldn’t it it form clouds the will eventually rain back down?
In: Planetary Science
Like Newton’s Third Law: for every action, there is an equal and opposite reaction. A drought in one place usually means an excessive amount of raining in another. Sometimes that rain just falls in the ocean, sometimes the rain is over land, but the problem is that none of it is landing where the drought is. A drought doesn’t mean that rain has stopped worldwide, it’s just that rain isn’t being spread equally.
The warmer the air the more water it can hold so some of it is in the air.
But the real anwser is water that evaporates in one place usually doesnt rain down in the same place. So yes it forms clouds and rains down that doesnt mean it will rain in the area where the drought is.
Often droughts in once place even means flooding in another area.
A further problem is that even when it rains in the drought area when the ground is dry it has a much harder time to take in water meaning a lot of the water doesnt get into the ground to help the plants but just leads to more water going down rivers.
It rains or snows somewhere else. Because of how big the ocean is, likely over the ocean. This keeps happening. You get a drought.
Funny thing. As the climate and the oceans warm, more water evaporates. Overall, across the world, more clouds from. More clouds, more rain. Then what kills crops is not droughts but too much rain because there’s not enough pauses in the rain.
It is not really that is go anywere but that is do not arrive to begin with in the drought area..
The water cycle is a bit simplified water evaporation in the ocean, transported in clouds and the fall on land as snow and rain. The water then flow back to the ocean. Drough is most of the time a result of weather pattern that result in the rain not falling over a area over a extended period of time.
The water fill fall down on another location on land or directly on the ocean. Other land location can get so much precipitation that the result is flooding.
So drought is primary a result of reduced precipitation in a area.
Meteorologist here.
So, it turns out that major weather patterns are caused by waves in the atmosphere…HUGE waves. You know when you see a weather map and they show the jet stream waving over the continent? That’s how big these waves are.
Now, these waves usually move, west to east. And like water waves, you have parts of that wave which are rising, and parts which are falling. Rising air cools, and then the water vapor condenses, forms clouds, and (if conditions are right) rains. There are differences depending on terrain and water sources, but that’s the gist.
Areas where the air is descending warms…which means that you don’t get cooling and thus you don’t get clouds. These are your “ridge of high pressure”.
However, you often get a situation where the waves go stationary. When this happens the ‘rising’ and ‘descending’ parts don’t move. For a week, two weeks, months even. And even if you get a bit of a break down in that pattern, a week later it sets up again. This is frequently caused by El Niño and La Niña over North America.
So you get situations where those descending air regions stay over the same spot. No clouds, no rain. Additionally you can then get secondary effects because the lack of clouds increases the temperature, which can dry out the soil and it gets hotter.
You can get puffy cumulus clouds in these high pressure areas, if there is enough moisture, and you get some small bits of instability (especially over mountains). But because the air is descending, you can’t get deep convection which is needed to form thunderstorms.
Edit: for some reason I thought you were asking why droughts happen. But it’s 3am and I really should go to bed. 😆
Water generally flows from land into rivers and those flow into oceans, then that water evaporates and rains down back over land. (there is also a lot of rain from oceans back to oceans and land back to land, but the big movement of water that matters in this case is oceans to rain on land and rivers to oceans)
But sometimes the wind blows in a different directions and the rain doesn’t fall over a certain area for a while, and when the ground is totally dry then it doesn’t absorb the water well and it flows into rivers and those rivers back into the ocean.
The probability of clouds pouring down in the form of rains is way higher on the ocean than on land because of the sheer surface cover of ocean
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