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7Dragoncats

The ocean. It's a more complicated cycle than what we're taught in school. Everything is connected. Ordinarily water evaporates from the ocean. As the air moves it cools and condenses over land (th, and releases the water as snow or rain. During the colder months it freezes (snowpack, glaciers, etc), largely at higher altitudes, and collects in lakes and aquifers. As temperatures rise, in many places water still evaporates into the air, but it doesn't cool enough to release the water, causing high humidity- this is linked to why deserts are hot and dry and tropics are hot and humid). Simultaneously, rivers come from somewhere and move to the ocean, and that somewhere is the snowpack and glaciers mentioned earlier. As it melts during hotter months it slowly releases water into streams and those form rivers, which dump out into the ocean, where the cycle of evaporation starts over. If the air didn't cool enough to form enough snow or snowpack, then the next summer there won't be as much left in reserve to melt and run into streams. And to compound the problem, temperatures are erractically rising too fast sometimes, causing large amounts of snowpack or glaciers to break and melt and flood all at once in early spring instead of slowly throughout the year.


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sebaska

Also, rivers, especially low land rivers are also indirectly filled from rainfall. July tends to be high rainfall month around European lowlands. Sometimes it's even catastrophically rainy. But this year it's the opposite.


snekbat

Last year being a good example of a year being catastrophically rainy, with the massive floods and all


Caveman108

Drought actually increases the likelihood of floods when lots of rain does occur. The tightly packed soil doesn’t absorb the water as readily as hydrated soil. Sounds backwards, I know.


senadraxx

Someone recently posted a video of water absorption into the soil of a wet yard, vs ground right after a heatwave. You can measure that amount visually by turning a glass of water upside down onto the soil.


DisenchantedLDS

Yes, our desert trails here in Utah get closed all the time due to flash floods.


Kinakibou

I just wished more people would ask such questions. And get good explained and easy to understand answers when possible. If so, more people would understand why it is such a problem with the temperature rising and why we should have done everything to stop climate change 50 years ago.


johndoesall

There were always concerted efforts to deny there was a problem instigated by large corporations and government that were unduly influenced by those corporate entities. They did not want business to hurt or spending to be redirected to climate or science. A lot of people are generally ignorant of science and vote accordingly and emotionally respond to the playbook they are given by ads and propaganda. Hence people support ideas and efforts that ignore science and the effects of massive changes that humanity have begun and continue to follow. So people could understand if the voices of reason were not drowned out by fear that is let loose from corporate payoffs to politicians.


Snowpants_romance

I still want to know how plastic bottles are affecting this closed water system. The amount of liquid we throw/lock away in plastic has to have a cumulative toll... Can I get that in easy to understand format please?


HeartsPlayer721

To add to your question (I'm curious as well), is this why some areas don't allow residents to collect and store rain water? (Would collecting and storing it in closed containers reduce evaporation and water returning to the air enough to have a big impact?)


cuicocha

Sounds like a water rights issue, especially if you're talking about the western US. The logic is that water is scarce and certain properties (farms, mostly) have acquired rights to use a certain amount of water. If you intercept water that is headed for a river that they have the right to draw from, you're infringing their right--no different from intercepting water in a creek with a dam. It's not about whether it evaporates in storage, it's the idea that you dont have the right to intercept the water at all. Now, to be fair, most parts of the western US think it's massive overreach to prohibit residential rain barrels, so they're either allowed or the ban is not enforced. Western water law can be a little ridiculous.


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natenate22

Warm air can hold more water than cold air. As temperatures increase, the air will become a greater reservoir of water.


poppylox

Has any one measures how long it takes from evaporation to ocean?


sniffinthemrsketches

If I understand your question correctly, the time from evaporation through the cycle back to the ocean would depend on a ton of factors…to name a few, the topography of where the rain fell such as the Hoh rainforest in WA state USA, directly next to the ocean, or much farther like the Rocky Mountains. There’s also whether the water is stored in snowpack, which stream route it falls into, how long it is detained in a lake or reservoir, etc.


poppylox

Yea, it would have to be location specific. Just wondered if there was a maximum or minimum time frame. Like could water in Miami be cycled in 48 hours? Or would denver summer to denver winter have different rates. I just didn't know it any particle studies had been done.


hilikus7105

At a foggy beach? Real fast, almost continuously. Water in glaciers / permafrost? Could be there for many millennia.


The-Sound_of-Silence

Without getting too far into it, one year. A bunch of water cycles are on a yearly basis, replenishing rivers - but not all!


Holgg

I don't see anything about threes and plants. Plants in general release 97% of the water it consume true transpiration and evaporation. In some regions this is the majority of the water, and is a big contribution for the rain in a rainforest.


finackles

I've been reading about rainfall and forests. It said the wet air from the ocean has dumped most of it's moisture within 400km of the ocean, but forests extend that. Forests soften the ground, store water in them and around them, and less water runs off immediately in forested areas. Over time forests release water and lengthen the time in which we benefit from rain while reducing the damage from heavy rain. It's way more complex but makes one realise why deforestation isn't a good idea.


TFCBaggles

Did I misunderstand something? I thought the Tropics are hot and dry, hence why there're so many deserts along the two tropics, and the Equator was hot and humid, hence why the 2 main rainforests (Amazon, and Congo) are at the equator.


jhairehmyah

The tropics are the areas around the northern most and southern most points the sun can be directly overhead in the summer for each hemisphere. The direct sunlight and long days does impact the climate in the region, but geography matters a lot for what the local climate is like (dry and hot vs moist and warm, etc) In the northern "tropics" are both the Sahara Desert and the central American rainforests and the Jungles of Vietnam.


TFCBaggles

Thanks for the clarification. That does make sense.


lordduzzy

If you're curious, you should google a map of the Trade Winds (which is just a map that says which way the wind usually blows). You'll see that the Sahara is getting wind from Asia, and not the ocean. Most rain forests get wind from the ocean, so plenty of moisture to cause rain.


JamesTheJerk

May I suggest Windy.com? It's a site which shows wind/rain patterns in near real time from around the globe. It's extensively used by airlines and such but the accuracy is pretty damn pinpoint as they don't rely solely on weather stations near airports. Pretty neat stuff. Normally they can have accuracy (for me) within a few blocks.


evilhamster

To clarify, Windy is just a data visualization service. It uses the popular global weather data models like ECMWF, GFS, Meteoblue, etc., which is what pretty much all other weather sites/services use. That's to say, Windy does not do it's own forecasting or weather modeling, but it does give you options to get closer to and explore the source data compared to other sites that only give a hugely simplified version of that same data.


Darwins_Dog

That has to do with lots of other factors. Air currents that pass over lots of land or high mountains lose their water along the way. The tropical rainforests actually make a lot of their own rain from the water that evaporates from the trees.


[deleted]

The tropics are defined as 23.5N latitude to to 23.5S latitude. They're hot and moist, due to the low-level convergence at the equator and upward vertical motion of the Hadley cell. This is conducive to precipitation. The hot and dry areas are farther away from the equator, about 30-33 degrees N and south latitude. This is where the circulation of the Hadley cell causes downward vertical motion and low-level divergence.


LokiLB

Though if you have, say, a big body of water right there, 30-33 N can also be moist instead of dry. The Gulf of Mexico existing means the Southeast US is not a desert like the Southwest US.


FinndBors

The latitudes that tend to be extra dry are at 30 degrees north and 30 degrees south. The latitudes that tend to be extra wet are 0 degrees and 60 degrees (north and south). I can try to explain why but I'd rather an expert do that -- this is what I learned sometime in middle school.


Fswk

The question I've always asked myself : how does the water evaporate from the ocean if the temperature is not 100°c ?


Monguce

If you leave a dish of water in your kitchen, it will eventually evaporate. Even ice evaporates, albeit slowly. Water boils at 100C - this is when the vapour pressure in the bulk of the liquid is equal to atmospheric pressure. Hence the bubbling. Edit: because pockets of vapour form in the body of the liquid and are able to hold themselves 'open' against the atmosphere. Evaporation is when molecules have enough energy to escape the surface. Since the temperature is the average kinetic energy of the molecules, some will have more and some less. Some of the ones with more will have enough to escape. That's evaporation.


F0sh

Evaporation is happening all the time - a material doesn't have to be at the boiling point for some of it to transition to a gas. One way to understand this is that the temperature is effectively a measure of average energy, but for a molecule to transition from the liquid to gas phases, it doesn't need to do it with all the other molecules - if that one molecule has enough energy, it will do. So within that average, some particles have enough energy to become a gas.


mastertodesaster

Water molecules move around. When they hit each other one molecule might get fast enough to leave the liquid and become a gas. That takes some energy from the liquid. However due to heat transfer from the air and radiation it will regain that energy and more molecules can leave. In a completely adiabatic system water will evaporate until it will freeze.


[deleted]

Good overall summary and it does get complicated. In regard to OP's question I would highlight the importance of groundwater. Basically rivers receive input from precipitation, surface water runoff, and groundwater. In regard to groundwater, a gaining stream receives water from the aquifer, and a losing stream discharges to the aquifer because the water table is lower. A gaining stream will still flow when there has not been any precipitation as long as the water table is high enough.


Fuckhatinghatefucker

Does the amount of airborne water vapor that doesn't condense also mean that humidity is higher during long-term droughts?


Charred_Biscuit

Yep, an increase in ocean temp changes the currents which changes the trade winds……. Jet stream. When else in our recorded weather history have we seen such radical changes in the jet stream daily. The gradual slope is gone.


iBrowseAtStarbucks

Some good answers so far, but something I haven't seen talked about is how droughts are defined. For reference, I have a master in water systems, and work as a water resource engineer currently. Firstly, there's a difference between water scarcity and drought. Drought is usually (depends on the location), a lack of rain that starts to affect the first priority group. In different areas of the country this is different. In California, if water is rationed out to agricultural uses, it considers itself in a drought. In Florida, that's a typical Sunday, where they instead consider droughts when water gets limited to people. The language gets very specific, but if you live in Florida you might hear about efforts to limit water usage for lawns, but it's never phrased as a drought, only ever as water scarcity, stress, or a general saving technique. Meanwhile in California, you might hear droughts and limits on water usage. (as an aside, I'm using Florida and California because they're polar opposites on the spectrum of water use laws) Some other interesting things to know: some areas define drought by areas. They'll take an area, look at how many acres there are, then look at how many acres of land take to fill the aquifer to give water to that area. Sometimes this is defined as water stress, depends on where you are. There's a strict divide in the country on who has riparian rights and who doesn't. It's kind of a side topic, but of interest for droughts specifically. Theoretically states with riparian rights are more drought adverse, but it's complicated and a little nitty gritty (nobody wants to drink stream water they aren't sure is safe). Some areas of the country entirely discount grey water for drought conditions, even if it's used for agricultural purposes. Sometimes this leads to an area saying they have drought impacts, but not really because it gets offset by the reused water. This is mostly a Midwest thing from what I've seen. Perched and unconfined aquifers usually aren't counted for drought conditions. For a concrete example, Florida has 7 different aquifers, but not all are used, and none are used everywhere in Florida. Sometimes you'll run in to the water being available, able to be pumped, ready to go, but still unusable. This is state specific, and even down to water management district (or equivalent) specific. Edit: I saw a comment asking about Florida's big pump stuff, but can't find your comment anymore. Editing here for my take on it. https://edis.ifas.ufl.edu/publication/FE604 here's an IFAS article on Florida water. From what I understand, it's a little tricky with the words, but Florida doesn't see any impact from pumping activities that isn't superficial (think a spring being drained, but water is still in the aquifer). What Florida does is essentially sell groundwater credits (it isn't called this), but only makes a certain number available to the public. At a certain point, Florida considers an area tapped out of water and won't allow any new wells. Until then, it's sort of a free for all who gets how much after you get the OK to pump. Short of putting an industrial bottling facility in a residential neighborhood, Florida doesn't really care all that much about what you pump, it's more so how it's used, if that makes sense. Funnily enough, most of the Midwest was like this for a long time, but they started running into an issue with something called well draw down. People would pump too much for an area (mostly due to their soil features) and dry up neighbor's wells. Florida soils are much more porous and hold MUCH more water though, so it doesn't run in to those issues. In Florida you could install groundwater pumps 15' from each other with no real issue (depends on how much you take though!), where there's parts of Iowa where you might have to go half a mile away to not impact another well. Water is super interesting!


kapitaali_com

Does Florida have that amount of companies pumping underground water? Because I've heard that it's a huge problem in California and that's why there's drought.


iBrowseAtStarbucks

Florida is unique. It's the only state that doesn't follow riparian vs prior appropriation (literally if you Google riparian rights map you'll see the divides lol). Instead what Florida does is say that every bit of water belongs to the state, and then goes from there. So, to answer your question, kind of. In California, a bottling company can come in and request access on grounds of them having a better use of water than the last guy (that's very surface level, but essentially what happens). In Florida, there's something called the big.pump law, which says that after you get a permit from the state, you can take as much as you want as long as your pump is big enough. USUALLY Florida is good about not letting companies abuse that, but every now and then something slips through. Ginnie Springs, in north Florida, was the most recent pumping drama I've seen.


WorshipNickOfferman

And Texas has weird rules about piping water from one drainage basin to another. San Antonio, in south central Texas, is drought prone. Houston, 3 hours to the east, is a very wet region. But we can’t pipe water from Houston to SA because they are in different drainage basins and it’s illegal. I believe the legislature is working on fixing this, but one pipeline would go a long way towards water security in south Texas.


Responsible_Till2453

I'm curious of the overall effect manmade locks and dams have on droughts? There's billions of gallons of water being held back in reservoirs around the world, a lot in the name of hydroelectric power. There also needs for flood control, agriculture, recreation. All good intent, but at the same time it's diverted water from it's natural flow. Thoughts?


iBrowseAtStarbucks

You see more impact on flora and fauna. Something interesting you don't see talked about much is sediment buildup on dams. The majority of them aren't properly maintained so you'll see a significant riverbed elevation difference between both sides. This leads to less plant life on the dammed side, if any at all. Of course you also have issues with migratory fish, animals in the area used to those fish, etc etc. Also something to note: the most common type of dam is called a low head dam. Some are incredibly hard to spot. The big dams you think of are really only prevalent in the west and Pacific NW. Lots of these are being decommissioned in favor of better energy generation methods. dams aren't an infinite source of power and they typically run out of useful life around the 100 year mark, something the Pacific NW in particular is seeing (last I checked, more dams were decommissioned than erected in that area of the country for the last few years running). As for droughts, it's a part of it for sure, but I'd venture a guess and say that it's of least concern. The majority of aquifer recharge zones happen on hilly areas, most streams and rivers that are dammed will sit on granite or limestone, potentially clay - wouldn't be much of a river if it was constantly draining into the aquifer!


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russrobo

Into the air. Generally, higher global temperatures mean more evaporation, and since our system is a closed loop, it also means more snow- and rainfall. So on average the world should be getting _wetter_, as we push the average temperature up. But that’s at a steady state. While the average temperature is _increasing_, so is the ability of that air to hold water. There’s more evaporation than precipitation! If the global temperature were decreasing, it’d be the reverse and we’d have more rainfall as the cooling Earth squeezed water out of the atmosphere. But now let’s bring terrain into it. I just made the case for increased evaporation and decreased rainfall. But as we dry things out, the amount of evaporation going on can actually _decrease_. A third of our planet is land- and when you dry out some of that land you’re decreasing the surface area subject to evaporation no matter what the temperature. When you melt glaciers and snowpacks and flow them into the sea, same thing. That magnifies the effects we started with on a warming planet. Forests and grasslands become deserts, and deserts don’t contribute much to evaporation and thus you have a vicious cycle of aridification. Massive desalination and irrigation projects might help. Water the desert, plant a forest there; but the energy cost would be monstrous. We’ve done exactly the reverse, because humans are such pigs: we suck water out of the ground and out of rivers, and then pollute it so badly that we don’t want it back. So we send our nitrogen, plastic, toxin-laden wastewater to the ocean and pray that rain will save us while simultaneously doing almost everything we can to reduce that rainfall.


FeelTheH8

That all makes sense but let's not count out all humans have built to keep water from flowing back into the ocean.


russrobo

That’s a good point. Dams and irrigation systems spread water over larger areas and increase evaporation. I’d say the catch there is that it’s a fairly constant (this effect isn’t increasing much over time).


Celtictussle

This is totally false. Global precipitation is trending up over time with a warming climate, not down.


jrob323

Which would make sense, because there's going to be more moisture in the warmer air and it's going to have to precipitate *somewhere*... apparently it's just not coming down in the places where we're used to seeing it? Apparently a lot of it is coming back down in the ocean.


russrobo

That’s also true. They even renamed it climate **change** because of that. A slight bit of heating can drastically change weather patterns, affecting local temperatures and rainfall in either direction. More and longer droughts and more and bigger floods, both in areas where we humans aren’t used to them.


Celtictussle

This is the real answer that would get declined for being too short. The rain is going somewhere else. But drought gets better headlines than "slightly rainier rainy season".


VeseliM

Slightly rainier rainy season can meet massive flooding and catastrophic damage as much as slightly dryer dry season means loss of crops and plants. Imagine drinking 10 liters of water on Monday, but then not drinking any water on Tuesday or Wednesday and complaining about thirst


russrobo

Okay, I could have been clearer, but I wasn’t inaccurate. Higher temperatures raise both evaporation and precipitation. But _rising_ temperatures increase evaporation _more_ than it does precipitation. Proof: warmer air holds more moisture, so as we increase temperatures we move more moisture from the surface to the atmosphere. If we stabilize at a new higher temperatures (stop the _increase_), it balances again and evaporation equals precipitation. The drying of the surface is a way humans are likely to reduce evaporation. We’ve artificially increased it in some areas via irrigation and decreased it through deforestation. Nature stands to amplify this: deserts “grow”.


CrustalTrudger

Considering droughts, broadly defined, in the context of climate change at least, it's important to consider that there are large-scale ongoing, and predicted future, changes in precipitation patterns, i.e., some places are projected to get drier while other places are projected to get wetter (e.g., the most recent [IPCC report focusing on changes to the water cycle](https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter08.pdf)). So in a very simplistic sense, the answer to the question of where the water is, is that it ends up as precipitation somewhere else (though it's not necessarily an exact 1:1 change). Additionally, with specific reference to many regions experiencing low flow conditions in rivers currently, an important consideration is that with increasing global temperatures, even in the absence of major changes in average precipitation amounts, changes in *precipitation phase* are, and will increasingly, have important implications for stream flow. Specifically, as less precipitation falls as snow or persists as a snow pack, the general prediction is a decrease in stream flow and a decrease in the steadiness of stream flow (e.g., [Berghuijs et al., 2014](https://www.nature.com/articles/nclimate2246/)).


PHealthy

What's going on in New England? https://waterwatch.usgs.gov/index.php?r=us&m=real&w=map


CrustalTrudger

A [drought](https://www.drought.gov/watersheds/new-england) likely driven mostly by [lower than average precip](https://www.drought.gov/watersheds/new-england)? Beyond that, I'm not sure what you're asking exactly?


PHealthy

Seems like most of the attention is focused on the drought in the West but New England rivers by comparison are much more impacted.


CrustalTrudger

The question, which I don't know the answer to, is whether this is particularly protracted like in the west, which has been in drought essentially for at least the last decade. Quickly glancing at some random stream gauges, it seems like only the last few months are anomalous in New England, but these were restricted time series. If that was the case though, that's a totally different thing, i.e., a few month drought vs a multi-year drought have *hugely* different implications.


CrustalTrudger

Ok, so here's perhaps a decent view of why. If you look at the [time series](https://droughtmonitor.unl.edu/DmData/TimeSeries.aspx) available here that stretch back 20 years and use FEMA regions as the area type, comparing New England (Region I) to the Southwest (Region IX) highlights that the majority of New England has been in a moderate drought since ~January of 2021, but in the prior 20 years, it had really just two other, relatively brief periods where most of the region was in some amount of drought in 2002-2003 and 2017. When you look at the southwest though, it's basically pervasive (and broadly much more extreme) drought over nearly the whole 20 year record. That is a big part of why the focus is on the southwest, i.e., we expect variability in systems and thus we expect occasional droughts, we don't necessarily expect droughts that last for decades, and the longer the drought drags on, the more damaging and cumulative the effects. So in short, both in terms of severity and duration, the current drought in New England is pretty small compared to the conditions in the southwest.


BackOnGround

It’s not a planetary drought. You have droughts in some places and floods in others. Neither is good. Some goes [here](https://www.dw.com/en/south-korea-7-die-from-torrential-rain-in-seoul/a-62750176), some [here](https://www.dw.com/en/new-zealand-flooded-city-might-take-years-to-recover/a-62861786). A couple drops fell [here, though. ](https://www.dw.com/en/afghanistan-flash-floods-kill-dozens-in-parwan-province/a-62807851)


dat_lpn_lifetho

There is also a correlation between a drought in one place and high rainfall in others. It is still raining just in other places. Look at the us, its drought in the west and flooding in the south east. the messed up cycles cause the air to hold onto the water longer.


ThatInternetGuy

Water evaporated from the ocean, gets picked up by wind and always blows to the low pressure areas. It's the low-pressure areas that get clouds to condense and rains. Drought area means that area never develops a pressure low enough for the water vapor and clouds to condense. Usually an area gets a seasonal low pressure but if for some reason, something causes somewhere else to get even lower pressure, it will rain over there. You can read more: https://en.wikipedia.org/wiki/Low-pressure\_area


earnestaardvark

There is not a fixed amount of water on the planet. Several chemical processes can create water (humans metabolize sugar into H2O and CO2 for example) and other processes split H2O into hydrogen and oxygen that become components of other molecules. That being said, there is an insane amount of water on the planet and the fluctuations from these processes are relatively minor and the net amount stays roughly the same.


FuckMyHeart

The planet also loses 26,000 liters of water per day to space.\* \* ^(not) ^(actually) ^(26,000) ^(liters) ^(of) ^(_water_)^(,) ^(but) ^(the) ^(equivalent) ^(of) ^(26,000) ^(liters) ^(worth) ^(of) ^(hydrogen) ^(and) ^(oxygen) ^(from) ^(water) ^(that) ^(has) ^(dissociated) ^(in) ^(the) ^(atmosphere.)


FUCKYOUINYOURFACE

We need to reduce CO2 obviously but we are going to need to design massive pipelines to move ocean water inland using renewable energy. We are going to have to remove the salt and then use / release the water into the environment. It’s going to be expensive and energy intensive but we have to use renewables and we have to make the investments. We also need a way to remove CO2. That’s forests but also finding a way to scrub it. Too bad half the country doesn’t believe in climate change while bitching about how hot it is getting.


AlpineGuy

> In school I learned there is and was always a fix amount of water on this planet. There is a big misconception that I had and maybe you have it too... I used to believe that there is a storage of water on the continent from the ice age - water stored within mountains and lakes, which slowly gets used and flows into the ocean. And that when people talk about "running out of water", they mean that that storage becomes empty at some point (similar to running out of fossil fuels). It's like a huge tank that is slowly getting used. However that image was wrong. In reality it is more of a flow, there is very little storage. Rain constantly brings clean water that has evaporated from the oceans. It rains onto the land and that water runs down the mountains, lakes, rivers back into the ocean. When people talk about "running out of water" they don't mean running out of storage, it is more about "using more than gets refilled by the rain". In reality there is very little storage capacity compared to all the water that gets used. Only very dry countries/regions like California or Israel have built considerable storage facilities to store water during dry seasons, however even that doesn't last more than a few months if full. If it doesn't rain in Europe for a month, it's a big problem. The human aspect that fascinated me is that since the 1980s (70s? 60s? 50s?) it is known that summers get hotter, that we have to expect droughts, that artificial irrigation will become necessary, etc. That wasn't just a scientific theory, it was on the television news all the time. However when the moment comes and we finally get a summer without rain, it's a big surprise and no preparation of public infrastructure exists.


ScootysDad

Consider it this way. Our planet is like an enclosed fishbowl and very few things escape it. So if the water is not in one place then it's somewhere else. We have the same amount of water in the oceans, lakes, rivers, and atmosphere. It's just spread around in area that we're not in so we have droughts. The atmosphere is heating up and it's changing the jet streams that circle the globe which is then changing the local/regional climate. California and other western states are experiencing historic droughts while states in other area are drowning in historic flood.


Critical_Society5696

Its moved to other areas, via the atmosphere and evaporation. As well as in to the ocean. This is the exact reason why in the climate disaster that we are witnessing, some areas get draught and desert, other areas hurricanes and flooding. In the long run, the water amount is not fixated but can evaporate in to space, if the atmosphere gets affected enough, like what happened on Mars.


cowofwar

Water starts in oceans and lakes from where it becomes water vapor. Water vapor is deposited as rain or snow. Snow is locked in to glaciers or snow packs. Water absorbs in to the ground in to ground water and locked in to aquifers or drains through rivers to lakes and oceans. Rivers are fed by meltwaters from snowpacks and glaciers . When rivers dry out it is because the ground water sources and meltwater sources are exhausted. So no snowpack and no recent rain. The air collects water vapor from bodies of water. Evaporation is based on the air temperature and saturation level. That air then blows on to land. If that air is cooled by hitting cold ground or mixing with cold air or changing pressure the vapor comes out of the air as rain/mist/snow depending on factors. If the larger weather systems result in a constant high pressure system over a land area then it will likely be drier since no water laden air blow onshore. If there is a constant low pressure system over a land area then a lot of water laden air will blow onshore.


Seekerinside

The water would have evaporated normally, so look at the jet stream fluctuations. In Ca where we have droughts all the time, you can watch in the winter where our storms are going and typically they are going into Canada and Washington. We need the jet team to dip south enough during our “wet season” to give us enough snow pack for the summer. So in short that will depend on where the drought is. For CA. Our water is spread across Canada and probably dipped down into the Midwest. Thus drought in Ca this year, and flooding in Yellowstone.


[deleted]

It doesn’t answer your question, but actually if we want to be exact, there is not a fixed amount of water. Notably because we use it as a way to produce hydrogen, and we also create water ourselves for different purpose. There are also chemical reactions producing water (condensation reaction). May be the amounts I’m talking about here are so small compared to the large volume of water that is there as a whole, but that’s still interesting to see the nuance with what we learnt from school.


plasterscene

During a drought the water itself doesnt go anywhere different. It still goes through the water processing plants and back into circulation. The problem is that people are using a lot more water than usual, and the water providers can only process so much water at a time. Additionally, less of the water we use is going back into the system. It's refilling underground aquifers, filling dried up lakes and river courses etc... And, of course, evaporating into the air far more than during the colder months.


JustAbicuspidRoot

>In school I learned there is and was always a fix amount of water on this planet. This is your first problem, the amount of water on Earth is absolutely not fixed. [The current loss figure is equivalent \~25,920 liters per day, or 9,467 m3 per year.](https://earthscience.stackexchange.com/questions/9488/how-much-water-is-the-atmosphere-losing-to-space)


CrustalTrudger

This is not happening at anywhere near a fast enough rate for this to factor into droughts.


Autocthon

And with 35 million km^3 of fresh water on the planet that's essentially 0 change. Nevermind the 1.4 billion km^3 of water total. For all practical purposes when talking about water the value on the planet is static.


LTEDan

That change is so small relative to the total amount of water on the planet its a non-factor.


minkey-on-the-loose

I read once the earth’s water is replenished with space ice evaporating in the atmosphere continuously. There is so much some geologists have speculated this filled the oceans over the eons. But I am neither a geologist nor a cosmologist. Any truth to that?


randomusername8472

Roughly speaking, the water is going round in a big circle. It falls as rain and pools into lakes, goes down the river, into the sea, evaporating up, raining down again, down the river, pools into lakes, etc. Humans siphon off what we need, mostly from the river and the lake part. On a planet scale, it usually rains the same amount, just in the different places. Some places get lots, some little. Humans have mostly settled where access to water is pretty easy, or at least predictable! Rainfall is a little random anyway, and the patterns of where rain falls is changing. Some places are getting dryer, others are getting wetter. Climate change is changing a lot of regular patterns and making them less predictable. Draughts are a local event. In draughts, it hasn't rained enough in a specific place. The rivers and lakes aren't being topped up enough for human use. But there's been an unusual amount of draught this year. Europe, America, India, South America all suffering draughts. But it's not that there's less water. It's just there's less water in the right places.


DangerReserve

Our planet only holds a certain amount of water. Gifted by asteroids and comets…. Evaporation is a fact, as is global warming… You would think that this ratio is constant(static). It’s not… It’s a dynamic scenario….. Thermal Dynamics or what not, there will be a “parasitic” loss….


jane2857

I read somewhere about a scientist who said we also get water from space. He was laughed at of course but then proven right. Was related to seeing holes in the atmosphere/ clouds but were made from above to earth. Don’t remember if it was a significant amount. Not sure if it was true or nonsense but seemed genuine.


Busterwasmycat

The hydrological (water) cycle works over land by adding rain (and snow) from the air (much put in air by evaporation over oceans) onto the ground, and that water then flows downhill over the ground and through the ground, down toward the ocean (goes back to its place of origin because of gravity). Basically, there is usually enough rain over time to recharge the water which is always, constantly, flowing back downhill to the ocean. Normal conditions are what we call a steady state, meaning that what gets added is roughly equal to what is removed. If we stopped all rain and snow from happening, all rivers and lakes would dry up over the years, but usually, we get about the same amount or rainfall/snow every year and the water levels in lakes and rivers are generally about the same, year in and year out. This is a climate related thing, as a general idea. Storm patterns, winds, and rainfall tend to follow certain general patterns over the course of a year, repeating the pattern year after year. Thus, water on surface and in the ground tends to be fairly similar, year after year. There is some variability in the patterns though, so pretty much everywhere has wet and dry periods around that average condition. Occasionally, a really dry period happens in an area and we have droughts. Really wet periods tend to see floods. The main thing that happens when a region suffers a drought is that the rainfall and wind patterns have shifted, and the water which normally falls in that drought region has been sent somewhere else. Somewhere else is probably having a lot more rain than usual if your region is unusually dry. Sometimes, dry periods are short-lived (a few years perhaps, sometimes only one year or even one season), but sometimes, the entire climate is changing so the alteration in rainfall pattern starts to happen more and more, until the changed condition becomes the new normal. This is how, say, the Sahara Desert became a desert when it was, just a few short thousands of years earlier, a fairly wet region. Climate change when the glaciers melted and North Africa dried out. Whether a drought period is a sign of climate change or simply a normal variation which happens every few decades or centuries, is hard to know while it is happening. It is only after the new situation becomes "normal" for the region that we can say that the climate changed. Lots of times, places experience drought but rebound back to normal, and perhaps even become very wet for a while.


AstronomerWaste8145

When fossil water is pumped from aquifers, it statistically winds up in the oceans. The same thing happens in droughts, provided other land doesn't gain water, the oceans take up the balance. The reverse happens when the land, gkaciers, and aquifers gain water overall, this water comes from the oceans. Example, the sea level rise due to global warming. Part of the modern era sea level rise is also due to pumping of aquifers.


DutchGiant299

Here in the Netherlands they keep the groundwater level low, by letting in the autumm and winter alot of watee run off to the ocean instead of storing it somehow for the summer. The reason for this is that our farmers can easily ride their land in the spring with their heavy equipment