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Earth Power Technology

Wind Farms Can Interfere With Doppler Radar 179

T Murphy writes "Wind farms can appear like storms or tornadoes on Doppler radar when placed too close to the radar. Tornado alley is a good area for wind farms, and good terrain for the turbines is also ideal for Doppler radar. With many new farms being constructed, the problem is growing. A false tornado warning was issued in Kansas by a computer, although canceled by a meteorologist aware of the problem — there are fears that false positives will grow. Worse would be a tornado ignored as a wind turbine. While meteorologists are trying to work with wind farm owners to shut off the turbines during bad weather, they have no control over the placement or operation of the turbines. Efforts are being made to improve detection technology to avoid further problems."
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Wind Farms Can Interfere With Doppler Radar

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  • Simple fix? (Score:3, Interesting)

    by B5_geek ( 638928 ) on Sunday August 30, 2009 @03:13PM (#29253647)

    Of course the turbulence will look like tornadoes, but can't they adjust the sensitivity to "if vortex 3m ignore" Or set them to scan Higher then 100m Or whatever the tallest turbine is in that region?

    • Re: (Score:3, Insightful)

      Comment removed based on user account deletion
    • Re:Simple fix? (Score:5, Insightful)

      by E-Lad ( 1262 ) on Sunday August 30, 2009 @03:26PM (#29253757)

      I'm not sure that you realize the limitations of the radar systems themselves.

      The nexrad doppler radar system uses systems designed in the early-mid 80's. Three meter resolution? Try 1km during the best situations.

      • We've got better systems than those, they're just not deployed in the civilian sector. Unfortunately, they're not likely to be deployed anytime in the near future. Lots of reasons for that, expense being one of the primary issues. Note that I don't necessarily agree with the expense argument in an era where we're tossing billions into government bailouts of every conceivable kind, but that's life in these United States these days.
    • Re: (Score:2, Interesting)

      Eaven easier: Wind turbines don't move around - in other words: Their location is known and doesn't change.
      It should be trivial to filter those out. What a non-story.
      • Re:Simple fix? (Score:5, Informative)

        by whathappenedtomonday ( 581634 ) on Sunday August 30, 2009 @04:10PM (#29254043) Journal
        Also, AFAIK the turbines shut down at wind speeds >25 m/s / ~55mph
        Ah, found it here: [bwea.com] Wind turbines start operating at wind speeds of 4 to 5 metres per second (around 10 miles an hour) and reach maximum power output at around 15 metres/second (around 33 miles per hour). At very high wind speeds, i.e. gale force winds, (25 metres/second, 50+ miles/hour) wind turbines shut down.
      • Eaven easier: Wind turbines don't move around - in other words: Their location is known and doesn't change.

        That's what they WANT you to think...

        I don't know about you, but I never go walking at night because of the roving gangs of wind turbines.

        Back in my day, we didn't have any of this motile turbine nonsense!

    • Of course the turbulence will look like tornadoes, but can't they adjust the sensitivity to "if vortex 3m ignore" Or set them to scan Higher then 100m Or whatever the tallest turbine is in that region?

      Exactly. I don't see this being any more of an issue than either directly canvassing the research areas for wind farms or requiring wind farmers to report the locations of their farms to a database. ... now back to those birds... lol

      • For bonus points: Have the turbine control center send out a message to the database when turbines are turning on or off. We have this thing called "the Intarwebs" for that.

  • Sorry, I couldn't help it.

  • Simple solution - pan/tilt/zoom IP-based cameras placed within each wind farm where we can actually SEE if there's an oncoming tornado, etc. Very small investment considering the cost of the actual wind farm itself. Welcome to the new millenium.
    • Re: (Score:3, Insightful)

      by negRo_slim ( 636783 )

      Very small investment considering the cost of the actual wind farm itself.

      I'm sure the hardware investment would be relatively small, but the cost to put eyes in front of the screens would probably be much more significant.

      • Very small investment considering the cost of the actual wind farm itself.

        I'm sure the hardware investment would be relatively small, but the cost to put eyes in front of the screens would probably be much more significant.

        Nope. From the article it is quite apparent that weather researchers are already present to ring the alarm in the first place --- thus those can be informed of the simple camera resource concept that GetQuad suggested --- something that could take a good 15 seconds to look at and then make an informed choice from.

        Your skepticism implies a falsehood that simple and practical applications are not feasible with today's technology and innovation.

  • Maps? (Score:5, Insightful)

    by maxume ( 22995 ) on Sunday August 30, 2009 @03:20PM (#29253707)

    If only the wind turbines were on stationary towers, then they might be able to map them, and use such a map to inform their interpretation of the radar data.

    • Re:Maps? (Score:5, Interesting)

      by negRo_slim ( 636783 ) <mils_orgen@hotmail.com> on Sunday August 30, 2009 @03:34PM (#29253827) Homepage

      If only the wind turbines were on stationary towers, then they might be able to map them, and use such a map to inform their interpretation of the radar data.

      Exactly and then ignore the Doppler readings of that area, and instead take notice when a bunch of turbines suddenly go offline.

      • by genner ( 694963 )

        instead take notice when a bunch of turbines suddenly go offline.

        The only problem with that plan is that a warning is supposed to come before something bad happens.

      • If only the wind turbines were on stationary towers, then they might be able to map them, and use such a map to inform their interpretation of the radar data.

        Exactly and then ignore the Doppler readings of that area, and instead take notice when a bunch of turbines suddenly go offline.

        That answer is too simple! We *must* find an impossible flaw in this green tech! umm.. err... The Birds!!!

        (sarcasm)

    • Re:Maps? (Score:5, Informative)

      by Ungrounded Lightning ( 62228 ) on Sunday August 30, 2009 @04:18PM (#29254101) Journal

      If only the wind turbines were on stationary towers, then they might be able to map them, and use such a map to inform their interpretation of the radar data.

      If only the tip voitices stayed at the blades, rather than trailing for miles downwind.

      If only "downwind" was always the same direction, rather than moving around when the wind changes - especially when it changes rapidly during a storm.

      If only the vortices were reliably visible to the radar, rather than sending a variable strength return depending on how many raindrops are getting blown around by each section of it at any given moment.

      = = = =

      More interestingly: The conditions that form tornadoes are weather-driven but the exact location they form, path they take, and indeed whether the finally DO form, are dependent on local things that disturb the airflow. Like mountains. And buildings. And forests. And freeways full of moving cars. And big windmills...

      Tornadoes have been documented to prefer to form up a short distance downwind of expressways. Perhaps the twisting air behind the mills of a wind farm will trigger the tornadoes in that area.

      If so it might be good: Triggering them in particular, known, mostly uninhabited spaces. Triggering them when the storm is not fully formed so they can dissipate the energy as small vortices - maybe not even making it to the ground - rather than letting conditions build until you finally get a small number of big skyscraper-topplers.

      • by vlm ( 69642 )

        If only the wind turbines were on stationary towers, then they might be able to map them, and use such a map to inform their interpretation of the radar data.

        If only the tip voitices stayed at the blades, rather than trailing for miles downwind.

        If only "downwind" was always the same direction, rather than moving around when the wind changes - especially when it changes rapidly during a storm.

        If only the vortices were reliably visible to the radar, rather than sending a variable strength return depending on how many raindrops are getting blown around by each section of it at any given moment.

        You see the glass half empty, I see the glass half full. Someday, a PHD student is going to gather all that "useless interfering noisy junk data", filter it back into an extremely detailed physical wind model, to improve tornado formation detection and write their dissertation. I say someday, assuming that someone isn't already doing it. Possibly, in the future, it will be a marketing advantage to have a wind turbine generally upwind of a trailer park, because suitably advanced radar DSP technology makes

        • by EdIII ( 1114411 ) *

          it will be a marketing advantage to have a wind turbine generally upwind of a trailer park, because suitably advanced radar DSP technology makes it easier to detect tornadoes headed for the trailer park...

          I have a vision...

          A wide-eyed Jethro and Shalene in the property management offices while having "Advanced Radar DSP technology" being explained to them. "So you is sayin, that y'all know about the tornadoes before theys gets here? No shit... Shalene you go tell yo momma her wish is coming true.. we movi

        • Re: (Score:3, Insightful)

          by joocemann ( 1273720 )

          If only the wind turbines were on stationary towers, then they might be able to map them, and use such a map to inform their interpretation of the radar data.

          If only the tip voitices stayed at the blades, rather than trailing for miles downwind.

          If only "downwind" was always the same direction, rather than moving around when the wind changes - especially when it changes rapidly during a storm.

          If only the vortices were reliably visible to the radar, rather than sending a variable strength return depending on how many raindrops are getting blown around by each section of it at any given moment.

          You see the glass half empty, I see the glass half full. Someday, a PHD student is going to gather all that "useless interfering noisy junk data", filter it back into an extremely detailed physical wind model, to improve tornado formation detection and write their dissertation. I say someday, assuming that someone isn't already doing it. Possibly, in the future, it will be a marketing advantage to have a wind turbine generally upwind of a trailer park, because suitably advanced radar DSP technology makes it easier to detect tornadoes headed for the trailer park...

          Most people do not quite grasp the entirety of the level of technology and innovation that humans have attained to date. It is hard for those who do not understand this to see the glass as you did.

          An example of this:
          Right now I hear a TON of people constantly upset about plastics going into landfills "FOREVER!!"... I laugh about this because I kinda see it more of a temporary storage (given it doesn't get lit on fire or something lame).

          We have, in today's mechanical/software/systems engineering capacitie

      • You don't have to make your whole post italicized. Really, you don't. There are good rules on when to use italics, this isn't it. It's slower reading.

        • You don't have to make your whole post italicized. Really, you don't.

          I didn't intend to. Blew the end-italics HTML tag after the quoted paragraph and was rushed so didn't preview. Sorry 'bout that.

          (One advantage some other systems have over slashcode is that you can edit your posting up to the point where somebody responds to it. With Slashdot it's cast in stone once you post. IMHO a short window where you can fix typos such as the above would be good.)

    • by rm999 ( 775449 )

      This is related to the serious risk of false negatives - i.e. a tornado not caught.

      Scientists will probably try to model the effect the windmills have on readings, but that can become a full-time job with 10 to 20 thousand wind turbines in the US (this is an estimate, I can't find the exact number), and more popping up all the time.

      Also, the accuracy of these models may be a concern. Does the the effect wind farms have on radar change with wind patterns? If so where will the models get this wind information

  • While meteorologists are trying to work with wind farm owners to shut off the turbines during bad weather

    I must really be missing something -- it seems to me that during bad weather, these wind farms could really be craking out the electricity! Why would the wind farms _want_ to shut down during those times?

    • Re: (Score:3, Insightful)

      by Anonymous Coward

      Wind speeds above the maximum design speed will tear the mechanical gearing apart - that is if the wind surfaces don't rip off first.

      Most wind turbines already automatically lock themselves when wind speeds exceed certain design specifications to protect themselves from damage.

    • Not exactly sure, but this might be a clue: http://www.youtube.com/watch?v=c3FZtmlHwcA [youtube.com] ..

    • While meteorologists are trying to work with wind farm owners to shut off the turbines during bad weather

      I must really be missing something -- it seems to me that during bad weather, these wind farms could really be craking out the electricity! Why would the wind farms _want_ to shut down during those times?

      If the wind is too strong, they break. Same with masts and sails of olden wind tech.

      • Same with masts and sails of olden wind tech.

        Wrong. You do know what furling a sail means?

        • Same with masts and sails of olden wind tech.

          Wrong. You do know what furling a sail means?

          Is it a technique meant to reduce sail surface in order to prevent damage caused by too strong a wind?

  • by pw700z ( 679598 ) on Sunday August 30, 2009 @03:25PM (#29253755)
    I am not a meteorologist, but don't tornadoes occur because there is a horizontal boundary between two different types of air masses, and the tornado acts as a funnel to equalize the pressure between the two or something? Maybe wind turbines, and the mixed and turbulence they cause actually prevent tornadoes. Who knows? And, don't many tornadoes occur over particularly flat land? The turbines might reshape the landscape enough to disturb the atmosphere enough to prevent them. Turbines looking like tornadoes on radar make me think i'm not totally crazy.
    • Re: (Score:3, Interesting)

      by GPSguy ( 62002 )

      Hmmm. A couple of thoughts.
      1. The tornado isn't a pressure-equalization tool. Were that so, prediction would likely be a bit easier.
      2. Yes, wind turbines do modify the landscape. More to the point they modify surface roughness, and research at the National Center for Atmospheric Research is looking at how these changes might affect local weather. It's not quantified yet, so useful conclusions are unlikely to be drawn at this early date.

  • by Anonymous Coward on Sunday August 30, 2009 @03:38PM (#29253849)

    Wind farms look like tornados on radar --> wind farms and tornados are the same --> wind farms cause tornados

    Time to start a panic. Snopes here I come
    /
    /

    For extra credit:
    Tornados are a weather event --> all major weather changes are caused by global warming --> wind farms cause global warming

    • by sorak ( 246725 )

      Wind farms look like tornados on radar --> wind farms and tornados are the same --> wind farms cause tornados

      Time to start a panic. Snopes here I come
      / /

      For extra credit:
      Tornados are a weather event --> all major weather changes are caused by global warming --> wind farms cause global warming

      Umm...Global warming does not exist (according to Rush Limbaugh) --> Wind farms do not exist. --> People on wind farms do not exist.
      Ghosts do not exist. --> Non-existent wind farms are haunted (according to Rush Limbaugh).

  • Not such a big deal. (Score:4, Informative)

    by benjamindees ( 441808 ) on Sunday August 30, 2009 @03:39PM (#29253857) Homepage

    Tornado warnings are extremely vague. Anyone who has spent significant time living in tornado alley can tell you they are routinely ignored. And the new technologies that attempt to pinpoint tornadoes exactly (TVS, VIPIR) aren't as accurate as they're made out to be. False positives are nothing new.

  • by Anonymous Coward on Sunday August 30, 2009 @03:49PM (#29253913)

    IAMFWDWR (I am a meteorologist familiar with Doppler weather radar) and it doesn't worry me at all. There are lots of objects that cause the same types of problems, including rotating radar antennas and buildings.

    When a weather radar system is set up the technicians will do a radar survey of the area and then flag areas for the computer (called an RPG, Radar Product Generator) to ignore. For a wind farm they'd look for an area in low scan levels with a high spectrum width and low to zero velocity and tell the RPG to ignore them. If these areas are too far away from the radar, they won't even be noticed by the radar (all scans are pointed slightly "upwards" so even with the lowest scan level something 200 feet tall would not be sensed unless it was within about 4.5 miles of the radar, give or take) unless you have a problem with subrefraction where the radar beam is bent downwards due to atmospheric effects. This would probably be the only time that the situation would cause a false positive and a meteorologist with any amount of common sense is going to investigate the area as it wouldn't be moving at all and would only appear in one or two scan levels.

    The automatic warnings generated by a NEXRAD system are helpful, but are nowhere near foolproof. A competent meteorologist will be able to investigate the areas and determine if a weather warning or advisory is warranted within only a few minutes. (generally less than 30 seconds with a proper setup) Detection technology is already in place and easily enacted. Article is ignorance at best, and scaremongering at worst.

    • by mortonda ( 5175 )

      Thank you for that, and I would also like to ask, where is a picture of the supposed false alarm? Wouldn't the article be more informative if they had included that? I'm curious to know how it could even look the same.

    • by Thelasko ( 1196535 ) on Sunday August 30, 2009 @07:29PM (#29255499) Journal

      There are lots of objects that cause the same types of problems, including rotating radar antennas and buildings.

      Yes, I heard this story last week at my local Fox affiliate, WFLD. The chief meteorologist stepped in at the end of the story and explained that there are lots of things that can cause these types of problems. He mentioned specifically that condensation from a cooling lake at a nearby nuclear power plant looks like a thunderstorm all of the time. But since they know about it, they can ignore it.

      He concluded that he felt this story was blown out of proportion.

      • On Fox? (Score:5, Insightful)

        by Valdrax ( 32670 ) on Sunday August 30, 2009 @09:12PM (#29256123)

        So a Fox affiliate employee took the opportunity to...

        1) Downplay some senseless and sensationalist bit of fear-mongering...
        2) While saying something nice about a green technology that suffers from a lot of NIMBYism...
        3) And he based it all on solid science and some common sense?

        He was fired immediately after, right?

    • Re: (Score:3, Funny)

      by Kijori ( 897770 )

      IAMFWDWR (I am a meteorologist familiar with Doppler weather radar)

      IAASRWDUTPIWAITRAEAI (I am a Slashdot reader who doesn't understand the point in writing an initialism that requires an explanation after it.)

  • Military issues. (Score:4, Interesting)

    by Demonantis ( 1340557 ) on Sunday August 30, 2009 @03:58PM (#29253965)
    The United Kingdom military has had to stop the development of some wind farms because it would leave a blind spot to their early warning systems. Their government has doled out a fair bit of cash to find a solution to the issue.
    • Completely different issue there though, that one is due to the regular array of windmills acting like a diffraction grating and proucing multiple radar images of a given object. (Or so I've heard anyway).

  • Solvable problem (Score:3, Insightful)

    by hcdejong ( 561314 ) <hobbes@@@xmsnet...nl> on Sunday August 30, 2009 @04:06PM (#29254013)

    Wind turbines should have a more or less predictable (and hence, recognizable) radar signature. IIRC the US military use turbine signatures (of aircraft engines) as part of non-cooperative target recognition (NCTR), i.e. the ability to recognize the aircraft type from a radar return, without having to rely on IFF transponders. But this probably requires better radars and processing than Nexrad can provide.

  • by account_deleted ( 4530225 ) on Sunday August 30, 2009 @04:16PM (#29254085)
    Comment removed based on user account deletion
    • Answer from Jon Steward: Ah, you mean those oil & gas companies with their own armies killing dozens of people and owning whole foreign countries? Or do you mean those who use the US army, kill tenthousands of people and *invade* foreign countries? Because I'm not quite sure, which one you mean...

    • by EdIII ( 1114411 ) *

      What about all the people from the Key Atomic Benefits Office Of Mankind? They have a powerful lobby too...

  • If.. Then (Score:3, Interesting)

    by DynaSoar ( 714234 ) on Sunday August 30, 2009 @04:16PM (#29254093) Journal

    If the tornado is occurring where the wind farm is, it's the turbines.

    If the tornado is occurring where the wind farm is, and the electricity goes out, it's not the turbines.

    It'd be a damn shame with all this great technology and great problems to solve if they had to rely on a phone call to a guy at the wind farm who had to look out the window for them in order to know whether there was a tornado or not.

  • So... (Score:2, Funny)

    by bXTr ( 123510 )
    The wind farms are interfering with radar systems used to detect storms which have increased in number and intensity due to global warming caused by burning fossil fuels which we are trying to reduce by building wind farms. It's like a never ending cycle of bullshit.
  • by SnarfQuest ( 469614 ) on Sunday August 30, 2009 @04:20PM (#29254123)

    They should just go back to coal-fired nuclear power plants.

    • by MrKaos ( 858439 )

      They should just go back to coal-fired nuclear power plants.

      Why is this modded funny? coal fired nuclear is the safest power generation method since ever, the radiation decays overnight and is perfectly safe to use in all of our homes.

      Today

  • http://radar.weather.gov/radar.php?rid=buf&product=N0R&overlay=11101111&loop=no [weather.gov] Perfect example, if you look at the National Weather Service radar for Buffalo, southeast of the "o" in Buffalo you'll see an orange strip, there are about 100 windmills on hills about 25-30 miles from the airport weather station reflecting the Doppler back.
  • wind speed sensors (Score:2, Interesting)

    by zogger ( 617870 )

    Put simple wind speed sensors (and other weather reporting gizmos) at each big wind tower, have them automatically update that info upstream so it can be cross referenced. If the remote radar says tornado in the direction of a tower, but the tower only reports a 40 mile an hour wind...you can nail the false positives easier. Turn a liability into thousands of new weather reporting assets.

    • Re: (Score:3, Informative)

      I think most of the towers already have sensors, since they need them to detect when to shut down. The collection of data is another matter, but it shouldn't be too hard to do, some guys over here already did it [middelgrund.com]
    • by GPSguy ( 62002 )

      There are some pluses and minuses to this approach. A micronet of this scale in an isolated area could provide some interesting data BUT the data would be skewed by proximity to the big whirling thingies which would induce a bit of turbulence. More to the point, there's history available. When an an automated vortex signature is detected, the wetware needs to know there's a wind farm in the area, and look at the history. A vortex signature that forms out of nothing right over the wind farm is likely a f

  • by overshoot ( 39700 ) on Sunday August 30, 2009 @04:59PM (#29254367)
    Is this a problem, or is it a Good Thing we're missing?

    All of those turbines make pretty decent wind speed/direction instruments, and they're all connected. How much would it cost to rig data feeds from them to the weather data collection system? I mean, if the weather computers are reading a Doppler shift from an area where there are wind farms but the wind turbines are all indicating 80 kph winds in the same direction it's not hard to figure out what's going on. Likewise if they're showing major surface-level wind shear around a vertical axis!

    • by GPSguy ( 62002 )

      One problem here is the mechanical systems on wind turbines are a bit larger than the typical anemometer vane, so they also tend to exhibit more wear and degraded performance is likely to impede their ability to demonstrate a well-correlated wind velocity. One problem I'm working on is a good hub-height wind measurement and prediction system to correlate turbine power output with wind velocity to act as a status/fault monitor system. We could tell if the wind were in a particular range, but not really exac

  • And no one has realized that wind farms are static?

    1. Detect Tornado
    2. If it is at the same place as any windfarm
    2a Ignore detection
    else
    2b Register detection
    3 Make money, live free and sing.

    I prey for the death of people who come up with such dumb shit every day, but Satan has not yet answered me.

    Who will give me justice ?

    Jesus?

  • Simple fix... (Score:3, Interesting)

    by Bones3D_mac ( 324952 ) on Sunday August 30, 2009 @09:18PM (#29256155)

    Have these wind turbines registered with the National Weather Service and mark the locations in the system. Also, place transponders on the turbines to verify their operational status. If a tornado is detected near a known turbine location and the turbine fails to report its status, there probably is "something" in the area bad enough to damage a turbine.

  • Buildings cause the same problem; anyone familiar with coherence and/or constructive and destructive interference of electromagnetic waves (or any other type of other wave) would say "No sh*t, Sherlock!"
  • by Anonymous Coward on Sunday August 30, 2009 @09:47PM (#29256319)
    I work for NWS. False alarms are rare. The Mets know where the farms are and the signals are always there. While there is a chance of a mistake in the heat of battle - the duty Mets are usually overloaded with information during a convective event - they don't happen that often. A bigger issue is a farm degrades the performance of the radar around the farm. In other words, if there is weather right around the farm, you can't see it for noise.

    Here the real threat.

    Lawyers for wind farms who know they have a nimby problem know that one of the arguments will be the interference problem. The lawyers have learned that NWS/DOD/FAA (the radars are a tri-agency project) usually leased the land for the radars in the late 1980s/early 1990's for either 20 or 25 years, so the leases are coming up for renewal.

    In several recent cases, NWS/DOD/FAA have gone to the land holder to renew the lease only to find out the wind project has already leased the land for twenty years at 5x the rate of the government lease and get a notice the radar needs to be moved.

    Now moving a WSR-88D costs upwards of a million bucks. They are VERY large and engineering studies have to be conducted to locate a good location ... usually as high up as possible (but not too high), in a place that has as few places were the beam is blocked by terrain, where power and limited bandwidth can be had, etc. The studies done in the 1980's usually found that sweet spot, but it has just been taken away.

    So the radar could end up being moved at high expense to a not as good location. While the radar is down (there aren't any spares), coverage may not be available.
  • Air Traffic Control (Score:2, Interesting)

    by amiga500 ( 935789 )
    Having setup an ATC radar in Palm Springs, I can attest that the wind farms add a lot of noise to ATC radar systems as well as weather systems. Noise on the radar screen makes ATC more difficult, and increases the risk of accidents. The wind mills in Palm Springs are the small blade, fast moving type which birds like to fly into. I think the newer, larger wind farms are less of an issue for ATC radar. The slower moving blades can be filtered out. If they could build the windmills with flat edges, or us
  • .....after the number of Earth's wind mills reaches a certain critical population, the planet will fly away, leaving all air traffic in its wake.
  • 1. I find it absolutely impossible to believe that there's no cost-effective, technological solution to this problem. People upstream have mentioned the idea of putting remote cameras on the windmill towers, which seems quite reasonable.

    2. Even if we can't, um... so freakin' what? It's not like false-alarm tornado warnings are such a big problem - what's the worst-case scenario? People spend more time in their basements than they really needed to? Note that I'm not buying any argument that this could lead t

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