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Weather Monitoring Frequencies Subject to Pollution
jd writes "In a case of technology vs. technology, the ICU (the body governing the use of radio frequencies around the globe) has been asked to secure radio frequences used for weather monitoring. In-car radar, mobile phones and other commercial and military applications are now using these same frequencies. However, weather satellites can't simply be re-tuned. There is only one very narrow band that detects water vapor but not liquid water, for example. This frequency has been sold to developers of car radar systems. The more this happens, the less useful weather radar and weather satellites will be. The noise will simply swamp the data, making what is collected useless. The article doesn't give a 'doomsday' timeframe, when we'll have no better ability to forecast the weather than they did in the 1800s, but that is what they are talking about."
Well, I am not sure how great we are at predicting the weather now.
A kid at my son's school collected and analyzied common RSS weather feeds for a science project.
He collected the data and used it to judge how accurate the weatherman's predictions were.
Within 5 degrees and 25% chance of rain, he gave them credit. They got credit 50ish percent of the time.
He then analyzied other ways of predicting the weather.
By just saying that the weather today will be the same as the weather yesterday, he got credit 50ish percent of the time.
I don't say this to belittle the weather people. I do this to say that the techniques we use now are not the greatest in the world. If we need those frequencies because they are the only ones that work, then maybe the gov't should buy them back. However, if those frequencies are used because that's the old school way of doing it, well, they aren't working at that great now.
Don't bother asking the FCC for help - they're too worried about someone saying fuck or showing their tits. Seriously tho, what sort of idiot would actually sell these frequencies if they knew what they were used for?
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Why would your car radar be useful if the signal it emits is attenuated by water vapour? Drive through some fog & you're in trouble.. ?
No Norm, those are your safety glasses; I'll wear my own thanks...
"BSD: Free as in speech. Linux: Free as in beer. Windows 10: Free as in herpes." --Man On Pink Corner in #52607549.
Question to those who might know this - assuming the ITU agrees to these restrictions, how would they enforce them? The radar frequency was presumably sold by a national agency (a la FCC) which is clearly making money off the sale and doesn't seem to care about the reasons. So how would the ITU go about forcing them to behave?
Our cars are more important than anything else. Everyone should know that by now, including weathermen who can't predict the weather anyway.
Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
What are the car 'radars' that Dr. English speaks of? As far as I know, radar (and laser) detectors don't broadcast anything, they simply detect certain frequencies.
The article is based in the UK. Is there some sort of dashboard radar system showing up there which doesn't exist in the US? Or do the "smart reverse" systems (which someone in the US wanted to make mandatory) use the same frequencies?
"BSD: Free as in speech. Linux: Free as in beer. Windows 10: Free as in herpes." --Man On Pink Corner in #52607549.
Oh, wait, I think that was the 1980s. In the 1880s, we had that thing with a man with a brolly and a woman in a summer dress hanging from seaweed. You could tell the weather according to which one came out of the house. AFAICT, the reliability was much the same as today.
My uncle Jack sticking a wet finger in the air and saying "Arrh, it looks like a [fine|rough] day tomorrow - I think I need a wee dram!" was more fun though!
Sent from my ASR33 using ASCII
Nope. Ka has been a word for soul since ancient egypt, actually.
I just don't get this. Surely the $xe6 that FCC et. al. get is for them to check these things? That they should know what spectrum is used for what? As their Job?
Why should the weathermen actually have to tell them this? If it's in the science books??
Or is everyone as bad as the USPTO?
The FCC has the power to ban the sales and use of any device that would cause interference to these frequency bands. I've owned radio transceivers that were made obsolete and worthless by FCC decisions to reallocate spectrum to other uses. The FCC had no obligation to compensate me for the loss in value of the radio equipment or to offer me other spectrum to replace what was lost. If car radar units are a problem, the FCC can prohibit their sales and use.
Mea navis aericumbens anguillis abundat
They can't even friggn manage Power and Freq.
Bloody Idiots.
Radar detectors, and most radio receivers, do transmit low-powered signals on the same or similar frequencies to those that they receive. It's called local oscillator leakage/radiation. It's especially common in consumer grade electronics equipment. If you look at the block diagram of a superheterodyne receiver, you will find one or more local oscillators that are used to mix down the incoming signals to fixed intermediate frequencies for filtering, amplification and demodulation. These local oscillators are often a source of radiation due to poor design and shielding. Radar detector detectors and TV detector vans take advantage of this by listening for local oscillator radiation.
Mea navis aericumbens anguillis abundat
the ICU (the body governing the use of radio frequencies around the globe) The is in charge of radio frequency allocation? News to me. Seriously though, the sale of RF spectrum is just getting ridiculous. This just shows how over the top it is becoming. How much longer until we're selling colours?
Using the results of a period of observation, assign a classifying neural net to distinguish water vapor reflections from the morass of noise. With human training (specifically, teaching it to distinguish RF interference from water vapor) it would very well have a chance to produce a markedly more accurate picture.
Um, when you can SEE the clouds from space, you have a much better view of the weather than they did in the 1800s. Whether or not its raining currently underneath those clouds is perhaps less certain, but if you can see the weather, and you can place a phone call to someone underneath the clouds, you have a good idea of what its doing.
Sounds like the article is FUD.
I want to delete my account but Slashdot doesn't allow it.
Unfortunatelly, I don't think it's that easy. I think the best you can do is to create (encode) a pulse in such way that all other pulses would be considered pure noise. The real problem here is that there are requirements on how high the noise can be and still have a working radar... If you have too much noise, then it would drown the radar signal completely
Like this would never happen.
"It is a greater offense to steal men's labor, than their clothes"
Ever been to LA...
You can drive in any direction for between 5 and 20 hours depending on day and traffic conditions, and never leave the monotonous suburban landscape. It's the results of unplanned, unconsidered, growth. From space it looks like the great god of suburban blight dropped it "Splat" from high altitude like some surreal cow patty.
What the hell (you might ask) has any of that got to do with this article. The answer is that the same kind of thinking (or kack there of), is behind the morass that is our use of the electromagnetic spectrum.
Empire building, despotism, political back-biting, greed and intrigue, technology working around the ideocy that is our regulatory system, and nobody asking whether the left hand knows what the right hand is doing... A Chinese Fire Drill would look like close order drill compared the slow motion Loony Tune that passes for what we've got.
Sanity might look like;
1. Determine that spectrum which serves to valuable or significant a purpose to avoid protecting, and declare that sacrosanct. Being able to track water vapor by the way is one of those sacrosanct uses.
2. Give up on that selling the spectrum for fun and profit idea... it was a bad joke then and it hasn't gotten better with time.
3. Put the millitary on a sane leash (they really don't need 50% of the workable spectrum.)
4. Promote the hell out of advanced mutispectrum technologies and count the money.
We really need to get a few folks in the FCC who haven't technological myopia, and have the cojones to push through an agenda based on growing use, and growing technology.
Genda Bendte
Which group is ICU? That org doesn't ring a bell. It only makes me think of hospitals...
A little learning never hurt anyone.
ICU's are found in hospitals.
Fiat Lux.
What sort of idiot? Bill Clinton? Tom Daschle? They're always looking to sell stuff for tax revenue. They want to leave their legacy. "I fed the poor!" Really, they fed about 1/2 the poor, and spent the other 1/2 entertaining lobbyists.
legitimately in the first place.
The spectrum is a natural resource which belongs to everyone equally. No one, and no government, has any right to "own," or sell what belongs to everyone. The only legitimate role of government in spectrum is to regulate it to maximize the public good. It is false to assume that "selling" spectrum provides any public benefit at all (although those who support that would argue that increasing government revenue is somehow "good.")
Spectrum allocation is a large, time-varying, multivariable optimization problem. This document is an outline of some of the service requests/requirements, and how they need to mesh with each other, present and future technology availability, and physical limitations (like attenuation due to water at 24 GHz). Note that this document is only U.S. interests; every other country has a similar list, and all have to be coordinated. It's like the guy who goes into a store with three lists: What he wants to buy, what he needs to buy, and what he can afford to buy. Compromise is the name of the game, and reasonable people will make reasonable tradeoffs differently.
The radar this article is discussing is a proposed future use of 24 GHz for collision-avoidance radar in passenger cars. 24 GHz is a popular frequency choice for short-range applications like this specifically because of the atmospheric attenuation. Note that the attenuation at 24 GHz, while higher than at other nearby frequencies, is still relatively low, only a few tenths of a dB per kilometer (although much higher in rain). This makes 24 GHz a good compromise for short-range devices on the Earth's surface, especially low-powered devices with very directional antennas pointed horizontally, away from satellites. (A better choice from this standpoint would be the oxygen absorption band at 60 GHz, and there is indeed another radar band there.)
Meterologists are merely expressing their concern over how their measurements will be corrupted if millions of car radars are in operation, and their cumulative power is enough to be detected by their sensors. My personal opinion, however, is that 24 GHz is too low of a frequency to make a market-successful car radar; the antennas are too big. I think 60 or 77 GHz is a better bet; if so, that would preserve 24 GHz for water vapor measurements.
In general, though, the interests of meterologists and others performing microwave sensing of the earth should be considered in the frequency allocation process; the publicity due to this article is one way of accomplishing this.
It's the same with BPL. Now it's more important to use the frequency spectrum for businesses, despite its critical importance for public services. We will see the consequences in some years; just wait for the coordination in case of a catastrophe failing due to HF pollution, or to miss the prediction of an important storm due to polluted data.
It seems that nowadays there is a sort of inherent "right" to turn anything into business, completely ignoring the impact to the public.
Ok, water vapor sensing is exactly what I did for my master's thesis. I'm going to keep it brief though.
Water vapor has an absorption line centered at 22.235 GHz while liquid water's absorption increases with frequency^1.95. Vapor sensing radiometers do not generally measure at 22.235 GHz because the peak of the absorption line curve is extremely sensitive to pressure. There are points to either side where the curve is insensitive to changes in pressure allowing measurement throughout the entire atmosphere without having to know the pressure profile. That is why the scientists in the article want to keep the 23.6 to 24.0 GHz band for their measurments.
My radiometer measured the emission spectrum at 21.6, 22.235, and 31.6 GHz. 21.6 and 31.6 GHz were the measurements of vapor and liquid water, respectively. 31.6 GHz is a window between the 22.235 GHz vapor line and the group of oxygen lines around 60 GHz. This makes liquid the strongest contributor to the noise temperature at that frequency. The 22.235 GHz was to experiment with. By using 22.235 and 21.6 I tried to see if I could get reasonably similar results even though both frequencies were more sensitive to vapor than liquid. Two close frequencies are measureable using one antenna thereby making the radiometer less expensive and available for more widespread use. I showed that the measurement could be made, but a lot more data needed to be taken to refine the data processing. Enough information was there in the measurements, but there were factors I couldn't account for in the time I had. Hopefully in time, radiometers could become a much more common piece of weather sensing equipment. You can get a lot more data on vapor with a radiometer than you can with a weather balloon, but radiometers are currently expensive and therefore limited in usability. Water vapor is the single biggest driving factor in the weather, we NEED to be able to measure it. Cheaper radiometers would let us get more data and improve weather modeling.
Pollution Monitoring Frequencies Subject to Weather..
eh.. il go now.
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Isn't the current weather prediction pretty much like the 1800's anyways? I get a better predictability just by watching the barometer on my patio that by looking at the official forecasts.
11*43+456^2
And, no, I'm not new here, I'm just thick-headed.
Have you been touched by his noodly appendage?
People tend to view weather accuracy on a micro scale, but meteorologists can only work on a macro scale. If you look at satellite images from Canada's weather service, you can see that the city you live in is less than 1/20th the size of a pin-prick relative to a weather system.
When a weather report going out 24 hours into the future says it will rain, it WILL rain... just not perhaps overtop of your little pin-prick. Considering the complexity of weather, realistically how effective can we expect a 3-day outlook to be?
All I'm saying is think big, and you'll realize that meteorology is an inexact science, but is so very valuable as a critical service. Nobody will ever be able to 'stick their head out the window' and have a hope of predicting anything. Meteorologic science deserves a hell of alot more credit than the farmer's almanac.
See how close those frequencies are on this chart: http://unihedron.com/projects/spectrum/
Terribly creative, imaginative, she.
But she sells it _all_ for money.
A pity. Beautiful, but no one asks her out anymore.
The spectrum is a natural resource which belongs to everyone equally. No one, and no government, has any right to "own," or sell what belongs to everyone. The only legitimate role of government in spectrum is to regulate it to maximize the public good.
..." part. Or it works because the dictator is paying attention, is exceptionally smart, and is benevolent - this week.
The same could be said about land, or water, or trees, or grain, or edible animals, or sexual partners, or the products of other people's labor, or any other desirable thing that is either consumed or busied out by use. (In fact, it often HAS been said.) And it sounds just as sweet and cuddly (the first time you hear it) when applied to any of them.
But it only stays sweet and cuddly until you try to apply the nicey-nice idea to make actual decisions to settle actual conflicts-of-desire. Then it all goes to hell.
When two (or more) people have differing desires about how a particular piece of some resource is to be used (or remain unused) you have a conflict. Only one of them can be satisfied. In millions of years of evolution (including all of human history and invention) only two non-violent ways have been found to settle such conflicts:
1) Dominance.
2) Territory.
Dominance is authority. The highest-ranking decides. The government tells you what to do and what not to do. The company president gets 10 times the salary and 100 times the stock options. The big ape gets the banannas. The bully gets your lunch money. The jocks get all the non-mousey schoolgirls. The guru gets to sleep with all the chicks.
Territory is property. The bird chases others away if confonted near his nest, flees if confronted near someone else's nest. When the lioness comes into heat the first lion of the pride she accepts mates with her while the others stay clear. "I'm yours, my love, and you're mine." The rest of the world may belong to someone else but this piece is MINE! If you want it, offer a swap for something I'd prefer, and accept my decision. Meanwhile, as long as I keep off YOUR pieces I can use it for any damned thing I please.
Dominance puts all the resources in the hands of a tiny elite - and even there gives no confidence, since the higher members trump the lower and the top dog is always ripe for overthrow. Territory lets anybody play. You might not have as MUCH as the big guys. But you have the confidence that you can do what you want with it, and that actually using it won't just bring it to the attention of a bigger ape who will take it away.
Territorial organization promotes prosperity for the little guys, self-esteem, and behavioral diversity. Authoritarian organization promotes constant conflict, fear, social pressure, conformity, and poverty. Even when it works well (as with a working commons) it works because conformity, driven by social pressure, prevents the "tragedy of
Consensus decision making is not the solution. It has been tried repeatedly - invariably leading to social conformity, misery, and authoritarian regimes (when the resulting poverty didn't end the experiment first). First conflicting desires lead to deadlocks and paralysis. Then social pressure mechanisms are developed to encourage conformity in order to break the deadlocks. Then, once the mechanisms are entrenched, someone (who doesn't care who gets hurt) realizes that by holding out for his position he can use them to run the show. And collective decision-making evolves into dictatorship.
The PRIMARY justification for government is to provide a single institution to track which piece of conflict-prone resource (such as land, or water rights) belongs to whom, help defend it against encroachment, and be sure it goes to the right heir when an owner dies.
In land the issues are obvious: There's only so much of it. It can be divided into chunks. You need the exclusive use of a chunk of it to establish a home, without which your standard of living
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
How could the "I-C-U" not see this? How did the car radar bandwidth get sold from underneath them? If it wasn't legit, then I say the ICU start flooding the vapor/car bandwidth with higher-powered light of that color. We'll see who's got the upper hand, and who relocates to another frequency.
--
make install -not war
Well, I am not sure how great we are at predicting the weather now.
As someone who's lived through a half-century of weather prediction technology, I can assure you that it's gotten a LOT better.
There's good reason to believe that, absent some major theoretical breakthrough, there's a "chaos limit" beyond which it can't go - causing the predictions to become unreliable after a few days - the number depending on the stability of the situation. And the current tools are able to both approach the limit and to estimate its location in the current situation.
Broadcast weather reports are NOT an accurate measure of the reliability of prediction technology.
First: They are oversimplified. They claim to tell you exactly what will happen at your spot on the ground - regardless of whether the prediction gives them a basis for doing so. "Scattered showers" might be dead on. But a hundred foot difference in a particular storm cloud's track means your city block get soaked or shined on.
Second: They are show business. "Nice weather, miniscule probability of disaster" will be predicted as disaster - both because it encourages viewers and because they don't want to predict picnic weather and then have the 5% chance of hail hit the jackpot.
IMHO even if they lose their satelite radar's reliability the predictions will get marginally worse but won't go back to what they were in the '50s. Part of the improvement is better data to feed the models. But that radar info is only a tiny part of the new measurement tech. Losing it just means the models sometimes start a bit further off, and deviate sooner. Part of the improvement is better models, and that will stick.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
cant understand why no one realizes this... your local weather is heavily influenced on geographical factors, just an short example:
clouds ->
spot A - ^HILL^ - spot B
so whats happening?
- clouds move over spot A, perhaps a bit rain
- clouds start "climbing" up the hill -> air cools down (Wet Adiabatic Lapse Rate, about -6 degrees/1000m) -> condensation -> rain!
- clouds climb down the hill -> air gets warmer (Dry Adiabatic Lapse Rate, +10 degrees/1000m) -> we have much dryer air due to the former loss of water and the higher temperature... usually the difference between rain/no rain...
Michael Powell's Incompetence ... They can't even friggn manage Power and Freq.
It's the policies Powell is currently promoting that brought you cordless phones and WiFi, and is bringing you UWB PANs, WiMAX, and a host of other stuff.
They're rehacking underused spectrum to make it easier to get new stuff working and deployed, and make it available to you sooner. Some is being sold off, some is being released to a commons.
It's an experiment to see which works better. And it's already bearing fruit.
Maybe the commons will work better. Maybe the property model will. But one thing we DO know already: EACH has already gotten more handy tech into consumers' hands than the licensing regime they replaced.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
What are the car 'radars' that Dr. English speaks of? As far as I know, radar (and laser) detectors don't broadcast anything, they simply detect certain frequencies.
What you are talking about are speedgun detectors, I assume (not sure, because here in Europe they are not very popular)?. The radars in the article are probably collision avoidance radars. The real stuff, transmitting and receiving signals to detect cars in front (slowing down). For my master's thesis I made an antenna for such a system operating at 26GHz.
Z
Car radar is used to for cruise control on Mercedes line of cars which is used to both adjust the throttle and even apply the brake when needed. They are the only ones I know that using radar based cruise control. Infiniti and Lexus both use laser based cruise control. If you have a radar detector you can actually detect people driving with their cruise control on.
Have you ever been to a turkish prison?
It's actually worse than that. Many of the water vapor sensing systems are passive and only measure the thermal emission so there is no opportunity for coding or any sort of similar gain.
And the knowledge that they fear is a weapon to be used against them...
That's why cars need the RADAR systems. The car talks to the driver and describes obsticals.
This issue is a bit more complicated than you think.
For all you algorithm specialists/electrical engineers, radio frequency interference (RFI) detection and mitigation is a newly emerging field that is mostly in its infancy. Interference in the water vapor emission bands is really just one example of all the RFI work that needs to be done. I went to a conference on this very subject, and yes people applied neural nets to the problem with a whole host of other methods but in the end it all just didnt work that great. And there are not too many people working on this issue right now. False positives (mistakenly thinking time slice x is RFI) are just still way to darned high to justify any of the systems I saw going on a space-flight mission. But youre up the right alley, this is definatly a machine intelligence issue. Besides remote sensing RFI issues, the communication systems guys down the hall from me are starting to talk about major investments for RFI related comm issues. And they have the big bucks compared to our group who gave 2 guys a measly $100K to build us water vapor sensor (radiometer) for the bench where we could inject noise and RFI in different parts of the system (I think an undergrad could have built this really). Take note.. :)
---------
No matter how thin you slice it, its still baloney.
That is how good we learn lessons.
I see there no conflict of interest between technology and technology, it is purely between cash-cow and public interest.
I live in europe and use the train and bike for 95% of my needs. Lanes of polluting traffic jam equipped with collision avoidance systems is just nonsense to me. Blood in the tank, carbon dioxide above, an undetected tornado a little further. Maybe there is still air somewhere between the ears of the driver.
Perhaps if we pollute the air enough, the frequency of reflection will shift to an unused band. Who says nature is not accommodating?
Table-ized A.I.
Yeah, i'm going to have to go with a lot of the other posts on this one, weather prediction is really pretty useless. I live in the pacific northwest, our weather isn't just rain every day, our weather changes rapidly due mostly to ocean conditions. The weather predictions over here are just terrible, almost completely useless. The only thing all of this satellite weather data seems to be good for is making fancy graphics for the weather man to stand in front of and make his false predictions.
Knowing where a hurricane might hit land is a good thing, but its such a large and obvious weather pattern i'm highly doubtful that any human interference could hide it. Other than that is there any sort of weather prediction that people find "vital", and is this prediction only possible through satellite data (i.e. just looking outside won't tip you)?
Everything's for sale. Duh.
DT
Is this thing on? Hello?
The weathermen amy not be any better than 50% at predicting ordinary weather, but tornados, rain-caused floods, huricanes, monsoons, snow-storms, heat waves, high winds, droughts, etc. are predicted far better now than in the past.
Would you like to be vacationing in Florida and get a huricane warning, or just get washed out to sea?
Would you like to be in the tornado cellar in Kansas, or take a trip to LA via tornado?
Get real.
Modern weather prediction saves lives, money, property, insurance, boats, airplanes, etc. now, whereas in the past people just lost everything, or died.
wake up and hold your nose
in the UK, you have to pay a license fee to RECEIVE TV
most Americans don't know that, of course
while I harbor warm feelings about the Mother Country, some of the things they do there are very scary, like, guns are illegal (yet they still have plenty of grisly gun murders, proving the old adage) and TV sets are effectively illegal (what's next, penalties for reading a newspaper?)
What you're failing to understand is that hurricane paths and velocities are determined partially by the amount of warm water vapour present in the air ahead of them.
Yes, we see the hurricane coming a long way away. We see that it's headed for the Gulf. The question is how fast it's going to be going when it gets there, where it's going to land, and how far inland it is going to go before it dissipates. If it passes over a large island, will it slow up? Will it go right over the tip of florida without slowing up much?
These questions can only be answered with detailed measurements of water vapor levels ahead of the hurricane.
Another kind of weather prediction that saves lives and depends on water vapour levels is flash floods. Knowing how much vapor is stored in the air helps know when to give flash flood warnings and how severe the flood might be. It's a sudden catastrophic release of stored water vapor.
To show off late at night, the BBC shows weather forecasts for random other continents (especially if there are certain sports events there). Hmm, Riyadh - it's going to be hot and sunny tommorrow :-)
Comment removed based on user account deletion
Nice idea, but you'll quickly find out that neural nets in radiative transfer are... well, to put it lightly... completely useless except for classification. So, yes, you may be able to tell what is water vapor and what isn't, but you won't be able to tell anything from a mass that has a little radio noise and some water vapor signal? What do you do then? Trust the measurement?
Neural nets are nice tools, but are not the solution to a lot of problems in radiation. If you just seek to classify, that's doable. If you seek to still get any meaningful measurements, good luck.
-Jellisky
Of course, the additional satellites and computing power required to do this would be hugely expensive but then again, so too is the cost of policing all this spectrum.
Is this practical? I'm thinking along the lines of a phased-array radar, or the techniques for constructing 3-D models from a set of 2-D images.