The Tragedy of Iran’s Great Salt Lake
nautil.us
nautil.us
I haven't been back to Urmia in almost 9 years but from what I hear the drying up of the lake has ruined the surrounding climate and destroyed the wild habitat.
The causes are known. We just used more water that we had. We built dams all over the rivers feeding it. Dug deeper and deeper wells to extract the ground water and here is the result. It's the sort of story you keep hearing over and over again, in different places with similar outcomes. When will it end? Probably with us.
What's happening to all of the Earth's water? Is it going into flooding in other parts of the world that don't come to mind? Are sea levels rising? Is our air getting more humid? Is it going into under the Earth's crust or under the sea floor? Did the single-catalyst water splitter get dropped into the ocean? Are we storing more of it in our food plants and food animals? Are we storing it in something else like concrete for buildings?
To the extent that there's increased evaporation, the water just ends up elsewhere, more or less randomly. Fresh water is a small part of the global water cycle.
Some of this could be "awareness bias" where people are more likely to be aware of information that's similar to other information they've received recently. Are we focusing more on apparent water shortages because of California?
Yes, the water is somewhere. Just so long as it's somewhere terrestrial, and not escaping into space like happened to Mars and Venus.
What's happening to all of the Earth's water?
That said, if Texas is any indication, and we get the same effects we saw in 1983, we're going to have a lot of moisture in the Cascades this year.
[1] http://www.weatherwest.com/archives/tag/ridiculously-resilie...
Consider that 97.5% of the world's water is salt water. Of the remaining sliver of fresh water, the vast majority of that (70%) is frozen in glaciers or snow. Only 0.3% of the freshwater of the world (0.0075% of the world's water) is in the form of lakes and rivers. Even if we dumped 10% of the water from all the lakes and rivers into the oceans it would only raise their height by about 30cm. Then consider something like the Ogallala Aquifer, which is the source of nearly a third of the water used for irrigation in the US, contains only 4000 km^3 total of water. If it were drained entirely it would raise the oceans only about 1cm.
Are we just not paying attention to newly-flooded parts of the world? Is there a floodplains in Malawi that's seeing record high water levels?
Which I don't intend as a comprehensive explanation, maybe just a wedge towards pointing out that estimating the amount of human managed/available surface water is not something that is easy to do by intuition.
edited to fix lake spelling.
- global warming - which beside increasing average temperature also causes increased amplitude of weather events, i.e. the drought is longer and drier, the storm is stronger and wetter (for example of weather machinery at work - http://news.stanford.edu/news/2014/september/drought-climate... for the CA drought and the East US storms.)
- unsustainable water usage like with Aral sea - diversion of water for cotton production in the desert. As result this water just mostly evaporates into atmosphere without reaching the Aral sea.
>What's happening to all of the Earth's water?
Short answer - we're happening.
https://news.ycombinator.com/newsguidelines.html
Please resist commenting about being downvoted. It never does any good, and it makes boring reading.
A tiny fraction of the world's water evaporates from oceans and falls as freshwater precipitation. Unless we expend enormous energy into artificial desalination plants, natural evaporation is the only desalinating process we have to get fresh water.
As human population grows, the fresh water per person falls in proportion. Iran has rapidly growing population from crazy unsustainable birthrates as part of the national policy of extreme oppression of women. California has and unsustainable mass immigration overwhelm its environment even as the native population wisely reduced birthrates to a sustainable level.
Most of the water is captured in reservoirs and diverted to agriculture. Growing food for people takes far more water than lawns and toilets and factories. Growing meat takes even more than other food, and people sure seem to like meat.
When water is used for agriculture, it mostly evaporates back into the air and falls back mostly into oceans mixing with salt water, so the fresh water is lost.
Older populations lived in wetter places where some water would trickle back into the water table instead of evaporating. Mass overpopulation has led to growing populations in places like Iran and south California where all the water evaporates due to extreme dry that would be uninhabitable without reservoir diversions.
The natural stream and lake life on Earth is dying out from diversions of rivers into reservoirs. That's what the op is about. It's all based in mass overpopulation. If we can't find a way back from our disastrously high numbers on this planet, we're going to see a lot more misery and tragedy.