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Dubai is making its own fake rain to beat 122°F heat (independent.co.uk)
153 points by kn9 8 days ago | hide | past | favorite | 99 comments





This is actually the reason why Miami is one of the few major American cities that's never broken 100 F in recorded history. When temperatures rise significantly above 90, then the chance of rain goes to 100%, which cools things back down. It's pretty much why you get clockwork torrential downpours every afternoon in Florida summers.

Tampa has that distinction for the same reason too. Afternoon thunderstorms can cause the temperature to drop sometimes by 20 F!

Singapore, on the equator on the end of a peninsular and surrounded by the sea, has a record high of just 37C (98.6F), lower than the record highs of Finland, Sweden, the UK, Japan, Korea, Russia etc.

The Maldives, also known for being reliably warm and just 4 degrees north of the equator, has a high even lower, 34.9C, only a handful of countries have a high of lower than that (Iceland and Greenland being two)

Of course they also have the highest record low temperatres (19C and 17.2C each)


Yep, loved Clearwater Summer rains and thunder. :)

Would you minding explaining the phenomenon in a bit more detail, if you could?

I thought that as air temperature rises, the air is able to absorb more heat, not less. And I thought rain was essentially the fact that there is too much moisture in the air, so it condenses. So this is counterintuitive to me (but I am likely missing something).


The warmer air over land rises up, cooling in the process. But then water in it condenses and gives up heat, that supports the upward flow. So it's kind of runaway process. Eventually when there's too much water condensed, then it overcomes the upward flow and rains down.

How it happens, and whether it happens at all, whether the rain won't evaporate in midair etc. depends on variety of conditions.


Ohhh that makes sense. And since they are so close to water, there is always an amount of humidity in the air too I suppose.

Thank you for the explanation!


Dubai is on the coast too, though. So there's something else going on. My guess is the dry sand might be a moisture sink and vegetation itself often puts out and collects a lot of humidity, but there's not as much around in Dubai.

Are there any known side-effects of inducing rain in an unusual place like this? The weather is a complex system, so I hesitate to speculate too much, but would it reduce rainfall elsewhere?

With geopolitical tensions rising over rights to the Nile, I wonder if rainfall patterns could follow a similar trend.


The amazon rain forest relies on minerals blown from dust storms in the Sahara desert, so therefore terraforming the Sahara would have a negative effect on the amazon. Source https://youtu.be/2hmAeLYMrQg

While this is true there’s a huge difference between adding rain to Dubai and terraforming the Sahara.

Wait 20,000 years and they’ll swap positions.

https://phys.org/news/2019-01-sahara-swung-lush-conditions-y...


> would it reduce rainfall elsewhere?

It will. I think it was The Economist, but it might have been some other magazine, who had an article recently, regarding Chinas usage of cloud seeding.

You're potentially "stealing" rain from other countries or regions. If it was just going into the ocean, then maybe it's fine, but if you're stealing it from a neighbouring country.


This reminded me of the "I drink your milkshake" scene from "There Will Be Blood".

For which the quote happened to be on last night's jeopardy...

… strangely, this reminded me of the ”There will be milkshake” scene from ”I Drink Your Blood”.

I wonder if China over-seeded and caused an impact in the American West.

Not in this case.

The vast majority of the population of the UAE lives in coastal cities and that is where the rain is induced. To the east, west, and north you have large bodies of water and to the south a (mostly) empty desert.


It sucks for places downstream of the jet stream. It could be good to end wildfires and droughts in California and Oregon but can't imagine the states to the east will be too happy.

Perhaps saltiness?


This is just cloud seeding. They’ve been doing it for decades, though not with drones.

The technique is different too. This uses electricity somehow instead of the chemical methods that are typically what people call "cloud seeding".

And didn't cloud seeding used to be chemical-based where this is electrical? Does that make this less sketchy?

> The enhanced rain is created using drone technology that unleashes electrical charges into clouds in order for them to clump together and form precipitation...Applying electrical shocks to clouds is preferred as it doesn’t require the use of chemicals.

Sounds pretty innocuous. I'm looking forward to reading comments about how this is dangerous and could cause unintended consequences. Only thing I can think of is perhaps that could reduce rainfall in neighboring areas which would have received the rain.


> Only thing I can think of is perhaps that could reduce rainfall in neighboring areas which would have received the rain.

…which seems significant, no? If you fast forward to a water deprived future (uh, present?) and give nation states the ability to take water that would have fallen on neighbouring countries and take it for themselves… I don’t see how that ends well.

Don’t get me wrong, the technology is fascinating and on purely technological terms it’s a great development. But yes, it could lead to some strange outcomes.


Clouds can also just evaporate if the temperature is hot enough, like in a desert. Regardless I think it's better to use this kind of method for cloud-seeding then the pumping chemicals into the air, which seems to be the common method.

If a cloud "evaporates", the water is still in the air and will condense into clouds and rain at some point somewhere else. It can't just disappear.

Sounds like the next iteration of downstream countries getting mad at upstream countries building dams on rivers.

E.G. https://www.bbc.com/news/world-africa-50328647


It's not like this is a new concept. Geopolitical considerations come into play all the time with shared waterbodies. Canada and the U.S. have treaties governing the Great Lakes, Egypt threatens war with Ethiopia over the dam on the Blue Nile, etc.


This already happens with dams which is arguably more devastating than rain cloud seeding.

Great point - also not to mention footgunning enormous bodies of water even within a nation http://www.columbia.edu/~tmt2120/introduction.htm

The Tragedy of the Commons takes to the skies.

Monty Python's Flying Surcharge

Like many things, it's about quantity.

Nobody would mind if there was one place on Earth which we would pollute in an extreme way. The problem is when we are polluting all over the place.

Now imagine if every major city started doing weather engineering.

It's unlikely that we would be able to have a giant effect, there is only so much energy we can put out, but local consequences could be pretty drastic. OTOH, local consequences will kind of fall in the same country.


Evaporative cooling for the win.

I wish (any) parks had this built in (ignoring splash/water parks), because it would be easier justifying brining kids out in this type of heat (especially for parks with no shade due to poor design).

It would also bring more community together to have outdoor areas that are dramatically cooler than the surroundings.


I have no idea why shade isn’t a primary design concern for every park. It is almost always left to “there’s a tiny tree over there that will produce shade in 25 years”. It is shocking.

I think the concern is the maintenance. Trees lose leaves in autumn increasing labor costs. They may also fall or have large branches break off in storms causing damage. I think its lazy and anti-environmental but less expenses ftw.

This is as good an explanation as I’ve ever heard. Seems silly though given the maintenance that already takes place with respect to lawn mowing. If trees are the concern then why not large fabric sails? The park equipment is super pricey to begin with so I can’t imagine we are taking huge extras.

No trees near water. Algae, maintenance.

It also means no one uses the park when it’s hot, so less maintenance in that regards. I could definitely design an unusable park that had zero maintenance fees :)

Heck, my neighborhood is 21 years old and the trees are still too small to provide any meaningful shade.

Just got to wait 4 more years then.

In Dubai, it IS a primary concern for pretty much every park.

it’s also not just the shade. for some reason plant cover is significantly cooler than just shade. i am not sure why

Evaporative cooling. Trees pump huge amounts of water from the ground into the air.

It doesn't work well most places west of the Mississippi (where evap cooling is most effective) because all the water is owned at least twice over.

> brining kids out in this type of heat

But dry-brining is all the rage right now anyway.


Ha, autocorrect has gone crazy on my iPhone, it replaces the word ‘has’ with ‘Hass’ as well…

”My hass is out.” — Ali Boulala in Flip - Sorry

I'm surprised they get even 4 inches of rain a year, but it seems like it's almost all in the winter. Assuming they can get another 4 inches during the summer, they can get as much rain as Phoenix. I wonder if this can dramatically change the landscape.

They probably get them in a few weather events every year. I lived in a place in the South of Portugal that, on paper, gets has much rain as, say, Berlin. The catch is that it would fall over 3 or 4 very strong downpours causing flooding and devastation.

I'd have thought with the amount of coffee grounds, leftover food and human manure from so many people, one could have turned their surrounding areas into a self sustaining green belt (with a little help from atmospheric water generation https://en.m.wikipedia.org/wiki/Atmospheric_water_generator#....

> electrical charges into clouds in order for them to clump together and form precipitation

So like … real rain?


Question! Is there any reason this technique could not be applied to solve the Oregon wildfires?

Last I read, the effectiveness of cloud seeding is still up for debate.

Wikipedia has a section on effectiveness, “A study conducted by the National Academy of Sciences failed to find statistically significant support for the effectiveness of cloud seeding.”[1]

[1] https://en.m.wikipedia.org/wiki/Cloud_seeding


Lack of clouds during wildfire conditions would be my guess

We've actually had a dozen mornings now in the Portland area with significant cloud cover. There's also been NW wind flow so if this technique only needed clouds and wind to push it in the direction of the fires, I don't see a reason why it couldn't work. Then again I'm no meteorologist.

The other comments here talk about hoarding potential for rain in the future and depriving others of it but what about weaponising it? You could potentially annihilate your enemy by generating masses of rainfall and destroying their infrastructure could you not?

It wouldn't be as targetted as a missile strike but you could easily say "it wasn't me!"...


If you have the ability to freely fly a bunch of drones in enemy territory there’s a lot of stuff you can do.

<sarcasm>No need to invade! You could just build a large antenna array to control the weather: https://presscore.ca/news/haarp-mandated-to-create-floods-to...

There are some crazy stories related to the HAARP program including opening holes in the ozone layer which caused instaneous skin burning to anyone caught under the hole. Even back in the early days of the internet, it was obvious how the conspiracy circles were going to flourish and push the drek to world. I had never heard of presscore.ca, but based on this article alone, I now know to hopefully never see it again except for examples like in this case.


Crazy thing about the "tinfoil hatters" is that they'll fight to the death to defend their pet conspiracy, but it's impossible for them to believe the much more plausible conspiracy theory that certain huge corporate interests conspired to sell out the entirety of humanity for ridiculous gobs and truckloads of short-term profits.

If you are really bored, you can cause lightning:

"A lightning rocket is a rocket that unravels a conductor, such as a fine copper wire, as it ascends, to conduct lightning charges to the ground. Lightning strikes derived from this process are called "triggered lightning."[1][2][3]"

https://en.wikipedia.org/wiki/Lightning_rocket

Of course, you can just drop some HE instead. Not sure how much damage lightning actually does.



Hmm... does anyone have beef with both Germany and China? The only connection I see between them is that they're both lender countries...

I got interested in drone tech and this source has more info: https://edition.cnn.com/2021/05/27/middleeast/clouds-electri...

Could this be used in California as an additional fire extinguishing method?

Unfortunately more fires are the only solution, due to the amount of fuel built up in California forests from a century of mismanagement. 2020 was the highest burn area on record with 4+ million acres burnt, and we would need 10 years burning at this level to bring the state down to 1920 fuel levels. The sad part is that due to the amount of built up fuel, these fires will be very intense leaving moonscapes opposed to healthy forests.

More prescribed burns in the spring and wet years may help, but I don't think the political willpower is there, given the liability if things get out of hand.


That's very intriguing and doesn't seem to be part of the popular narrative. Is this 'consensus' science, i.e. generally accepted, or is this a novel take?

Also what specifically has been 'mismanaged'? Wouldn't leaving nature to run it's course be a reasonable thing to do, or would this imply 'build up and then big fires every century'?

Also, do you know if it's the same in Australia?


My understanding is that this is the scientific consensus as the main contribution with climate change as an exaserbating effect. Most media coverage focuses on the latter for more clicks.

The mismanagement in this context is a century long policy of extinguishing natural fires and not letting nature 'run its course'.

The policy was briefly lifted in the 60s or 70s do to overwhelming scientific opposition, but reinstated due to public outcry after a few iconic locations burned.

The wikipedia below has some basic starting information, but generally whitewashes history, suggest that policy was corrected in the 80's. IF you dig deeper, around 100,000 acres were allowed to burn per year on federal land in the 90's and 2000's, which is far too low.

https://en.wikipedia.org/wiki/History_of_wildfire_suppressio...

Slide 4 of the PDF below gives a an example of the fire frequency in the 1800s in comparison to 1900s.

https://ucanr.edu/sites/firesummit/files/302800.pdf

I have no clue about Aussie fire policy, sorry.


Re: "popular narrative", I think this is just unfamiliarity with the source material. The unintentionally-disastrous fire management policies of the 1900s have been widely known since at least the Yellowstone Fire of 1988 catapulted forest fires into the public eye: https://en.wikipedia.org/wiki/Yellowstone_fires_of_1988#Fire...

The problem is that nobody wants to acknowledge that fire is a necessary and constructive part of the ecosystem. So they build their homes in wildfire zones and support policies that suppress fires until the pot boils over and the fire turns from constructive to utterly destructive.


The science goes back far further than that. Scientists were advocating for natural burns in the 1930s, when the Roy Headley, chief of fire control for the Natural Forest Service, wanted to allow burns but was overruled.

Indeed, I was trying to refer to broader understanding outside of the scientific establishment. It should be noted that the Yellowstone Fire of 1988 was actually a success of proper fire management techniques established in the decades prior; if those hadn't been in place, then the fires of 1988 would have been even worse. But to the public at the time who were uninitiated to the idea of the constructive power of regular forest fires, and facing the prospect of losing their most impressive national monument to fire, and after being inundated with decades of Smokey The Bear, it's no surprise that there was outrage at the forest management for allowing any fires to happen, despite their necessity (and eventual inevitability).

Home to some of the best and brightest engineers in the world and California is still figuring how many firemen, goats and firetrucks to send.

Where are Google, Facebook, Apple, SpaceX, California state gov?

And Musk is still focused on LA traffic jams. I guess the worst fires in California state history are not enough to sway the titans of industry into action.

Even though these fires are happening in their back yard.


Wildfires in CA are a political issue that will only be solved via a political solution, but at present, there is absolutely no appetite to do so among the residents or politicians. Its like asking why Elon hasn’t fixed healthcare or higher ed in the US.

there are a dozen efforts and a lot of money (captured mainly), and yes, a lot of high-tech in play right now. one link:

https://wifire.ucsd.edu/


Neither side (the government and these companies) want to get involved with the other

> The monsoon-like downpour drenches a busy highway,

Why is the word monsoon used for countries in the east and heavy rainfall or other words in the west? Is there a scientific difference?


My understanding is that monsoonal patterns are a result of seasonal heat causing a rising air column, which is then replaced by wetter air from over (relatively) nearby oceans. Wikipedia says that's no longer the preferred understanding, but then goes on to describe exactly what I said, so consult your local meteorologist. At any rate, "Monsoon" is a commonly used word in Phoenix understood to mean seasonal rain storms. This is in contrast to just "rain" which is not necessarily monsoonal in nature. We do get rain in the winter, occasionally, but it is not the monsoon.

I have read that they are using drone technology to create precipitation. Can the same method be applied in extinguishing forest fires?

so now we're saying weather control/manipulation is real then?

i guess the conspiracy nuts were right again.


We've been openly trying it since at least the 1960s.

The conspiracy nuts claim it's intentionally being used to make targeted natural disasters (and typically throw in chemtrail stuff), which is a very different claim than "we can probably increase rainfall a little bit'.


Subject reminds me of this short sci-fi animation I saw somewhat recently, worth the 10 minutes imho.

https://www.youtube.com/watch?v=uWCGK4nneeU


DUST ( https://www.youtube.com/channel/UC7sDT8jZ76VLV1u__krUutA ) is a great channel to subscribe to. It frequently has reasonably high production quality science fiction shorts.

Hah, I knew exactly what you referring to before I clicked and confirmed. Great piece of art. Thanks for bringing it up.

I'm curious how places out there by the sea like Dubai are essentially a desert. Evaporation should be massive at those areas no?

Vegetation evaporates more water, faster, than the Sun shining on open water body surfaces.

I've seen a picture from directly overhead of the Amazon river where you can see clouds forming directly over treetops on either side of the river, but not the tiniest wisp of cloud over the river itself.


[flagged]


UAE actually doesn't rely much on oil at all.

that means other region won't have rain

this should be illegal


A bit like the US takes water from large rivers that used to go to Mexico? But are now dry river beds before getting to the border (Colorado river?)

Perhaps the scope of "Convention on the Law of the Non-Navigational Uses of International Watercourses" should be expanded, or similar legislation

no region over there has any rain to speak of (but lots of humidity) so ...

aka cloud seeding, a lot of country does this

https://en.wikipedia.org/wiki/Cloud_seeding


> The enhanced rain is created using drone technology that unleashes electrical charges into clouds (..)

> Applying electrical shocks to clouds is preferred as it doesn’t require the use of chemicals.

So, a bit different than cloud seeding


The idea is pretty similar, in that the aim to to create cloud droplets large enough that precipitation forms in those clouds (hygroscopic cloud seeding). This is a little different from glaciogenic cloud seeding, where you aim to generate ice in a supercooled cloud (which has historically has been more common).

Glaciogenic seeding typically uses something like silver iodide (to nucleate ice crystals). For the clouds over the UAE (which are not supercooled), table salt would be more likely to be used. This idea is that it can create cloud droplets that are large enough to begin the collision-coalesence process.


Curious how saline that rain would end up being, detrimental to plant life, considerable corrosion for metals/cars/etc.

Just guessing but I can't imagine they use as much salt as northern cities put on the road when it snows (dump trucks worth of salt). There's information for that at my local extension office [1]. The TL;DR is that plants don't love it, but they tolerate it. Grasses are especially tolerant.

[1] https://plant-pest-advisory.rutgers.edu/impact-of-road-salt-...


They do it at the ski resorts here in CO.



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