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How Much Does A Cloud Weigh? 505

MyNameIsFred writes "ABC News is running an article revealing unexpected facts about weather formations. Ever wonder how much a cloud weighs? What about a hurricane? A meteorologist has done some estimates and the results might surprise you..." Reports that include the phrase "more than all the elephants on the planet" are always welcome.
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How Much Does A Cloud Weigh?

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  • by error502 ( 694533 ) on Thursday September 04, 2003 @02:01AM (#6866313)
    Clouds are made of a lot of water. A lot of water is heavy. Clouds are heavy.

    In other news, the sky is blue and grass is green.
    • by digitalunity ( 19107 ) <digitalunity&yahoo,com> on Thursday September 04, 2003 @02:18AM (#6866395) Homepage
      That's why I never listen to the news.

      The sky isn't blue at all. Sunlight shining through our atmosphere makes it appear blue. Evidence of this is any sunset; then it isn't blue at all.
      • by error502 ( 694533 ) on Thursday September 04, 2003 @02:21AM (#6866407)
        *Gasp!* The sky isn't actually blue! My world has been shaken! ...Grass is still green, right? ;-)
      • Re:Nonsense (Score:2, Informative)

        by CyberDruid ( 201684 )
        Of course the sky is blue. Look out your window and see for yourself. The sky is the cause of it's own blueness (by scattering those wavelengths better), thus it is truly blue.

        Perhaps you are thinking of the sun? One could argue that it is not really yellow, since outside of our atmospheric filter it is actually white.
      • by TummyX ( 84871 )
        Grass isn't green. Sunlight reflecting off it makes it appear green. Evidence of this is at nighttime; the it isn't green at all.
      • by glyph42 ( 315631 ) on Thursday September 04, 2003 @08:42AM (#6867693) Homepage Journal
        Then my shirt is not red, and my pants are not beige, because when I turn off the light, they're all black, right? Or if I shine blue light on them, they look blue! Wait, but that blue light is black if I turn it off, so it cannot be blue! In fact, nothing is any color! There are no colors at all! Revelation! Ack! I can't see!
    • by Negative Response ( 650136 ) on Thursday September 04, 2003 @02:21AM (#6866410)
      Um, I read the article, and doesn't it say clouds are made of elephants? Millions of them?
    • by jerde ( 23294 ) on Thursday September 04, 2003 @03:38AM (#6866686) Journal
      Wait...wait... slow down...

      Water? has Weight? But they look fluffy!

      Next you're going to try to tell me that the very air we breathe has weight, too. Bah. Silliness.

      - Peter
    • by WIAKywbfatw ( 307557 ) on Thursday September 04, 2003 @04:53AM (#6866873) Journal
      You get the giant stepladder and I'll get the big bucket and scales...
  • sad (Score:2, Insightful)

    by mse61 ( 678636 )
    It isn't saying much when you have to relate the measurement of weight to an elephant so the populous that reads it can grasp the magnitude of the number. In fact I find that rather pathetic...
    • no kidding, how did this get on slashdot? I've seen huge discussions of Tesla coils by people who design them for a living, and here we're talking about a cloud being heavy -- give me abreak.
    • by Chuck Chunder ( 21021 ) on Thursday September 04, 2003 @02:11AM (#6866363) Homepage Journal
      I see no reason why most people should have some natural appreciation of what "550 tons" actually means.
      • 550 tons (Score:5, Funny)

        by SysKoll ( 48967 ) on Thursday September 04, 2003 @02:53AM (#6866525)

        550 tons is the weight of all the electrons that have been inconvenienced, although momentarily, by people who read this stupid article online, and then couldn't keep from posting on /. about how asinine it was. (Oops).

        For that many electrons, we could have downloaded ourselves a few Libraries of Congress. Too late now, they're all wasted. We'll have to get the 20,000 CD-ROM worth of data [jamesshuggins.com] delivered to our door by an elephant.

        • Re:550 tons (Score:4, Interesting)

          by Idarubicin ( 579475 ) on Thursday September 04, 2003 @10:42AM (#6868761) Journal
          550 tons of electrons;
          divided by 9.1E-34 tons per electron;
          divided by 6.02E23 electrons per mole;
          divided by 96485 moles of electrons per amp.second;
          divided by 3600 seconds per hour;
          multiplied by 110 volts distribution;

          Gives 318 kWh in 550 tons of electrons, delivered to your door in North America, or twice as much energy in Europe.

          If you're drawing 400 watts for computer and modem;
          and you wasted fifteen minutes on this story;

          That's only 3200 readers to use up 550 tons of electrons. Of course, since we're using alternating current, those readers had to return the electrons for reuse by other /.ers. :D

      • by NanoGator ( 522640 ) on Thursday September 04, 2003 @02:59AM (#6866554) Homepage Journal
        "I see no reason why most people should have some natural appreciation of what "550 tons" actually means."

        Must... resist.. yo mama.. joke...

      • by RALE007 ( 445837 ) on Thursday September 04, 2003 @02:59AM (#6866555)
        I see no reason why most people should have some natural appreciation of what "550 tons" actually means.

        I know how much 550 tons is, that's like

        The weight of 9,500 ex girlfriends, or 550 ex girlfriends if you live in Utah.

        The amount of shit expelled in the average SCO press release.

        The weight of my formerly miniscule equipment after I replied to *every* penis enlarging piece of spam I've ever received.

        Since they insist on reporting on the weights of things relative to others, instead of just sticking to a standard unit of measurment, I say the pick more interesting objects than VW Bugs or Elephants. For instance:

        For extremely bad news, they could pick something friendly or cute to reference, such as "A comet with the mass of 7 billion cute fuzzy bunny rabbits is on a collision course with the Earth. I for one can't wait for the bunnies to get here!"

        For scientific news trying to get your average Joe Blows attention for future (hopeful) government funding; "In other news, a space probe weighing as much as 170 pairs of Pamela Andersons breasts was launched at Mars today. The rocket carrying the probe created a massive 18,000lbs of thrust to get the probe headed on its way. Although there is a slight possibility of damage to the delicate probe, the 18,000 pounds of thrust must be used on the mass of Pamela Andersons tits to enable it to build up enough speed, faster and faster as it goes, to escape the Earths gravity. I'm sure every man involved is very proud at the success and has a special feeling at the moment."

        Etc. Lame, but fun, try making your own.

      • by JohnsonWax ( 195390 ) on Thursday September 04, 2003 @03:21AM (#6866627)
        Don't lose any sleep over it. I see no reason why most people should have some natural appreciation of what an elephant actually weighs unless they've had to carry or eat one.

        Me, years of studying physics allows me to convert among numerous units of measure including the ever useful library of congresses, empire state buildings, highways to the moon, and popes in a volkswagon, but even so I'd sure as hell be suprised if 6 tons of anything showed up in my backyard, be it cloud, elephant, or bird shit.

        To me, 6 tons is about 5,000 kilos (grew up in the U.S., but I think in metric - how screwed is that) or about 5 of my car or 25 Powermatic table saws. It's all relative to what you're brain has stored. I've moved my table saw and I've had my foot run over by my car, so I have a direct appreciation for the weight of both, but not an elephant, or 6 tons as such.
  • I knew it (Score:5, Funny)

    by Kshu ( 608394 ) <j@postPLANCK.ro minus physicist> on Thursday September 04, 2003 @02:02AM (#6866316)
    I always knew that elephants could fly...
  • Depends (Score:5, Funny)

    by Timesprout ( 579035 ) on Thursday September 04, 2003 @02:03AM (#6866319)
    On whether it has a silver lining on not
  • Math? (Score:5, Funny)

    by robbyjo ( 315601 ) on Thursday September 04, 2003 @02:03AM (#6866320) Homepage

    Assume an elephant weighs about six tons, she says, that would mean that water inside a typical cumulous cloud would weigh about one hundred elephants.

    Somehow it reminds me of RIAA's math equivalent.

    • I always thought the clouds and vapor are more like SCO's claims equivelant ;)
    • Re:Math? (Score:3, Funny)

      by AntiOrganic ( 650691 )
      I would imagine that a zookeeper at a particularly large zoo, or perhaps safari, would weigh one hundred elephants.
    • Re:Math? (Score:5, Funny)

      by error502 ( 694533 ) on Thursday September 04, 2003 @02:12AM (#6866366)
      If that were actually RIAA math, one cloud would weigh about one elephants. You have to take into account how old they are. A really old elephant is equivalent to two middle-aged elephants. You also have to take into account if they know any circus tricks. The elephants that know circus tricks are equivalent to the weight of five regular elephants. Then there are the wild elephants, which are the equivalent of ten elephants that grew up in zoos.
  • by drinkypoo ( 153816 ) <martin.espinoza@gmail.com> on Thursday September 04, 2003 @02:03AM (#6866322) Homepage Journal

    Or a physicist, or really a member of any pertinent field, but it seems to me that the last bit, about all the elephants ever, is pretty bogus science.

    "What we're doing is weighing the water in one cubic meter theoretically pulled from a cloud and then multiplying by the number of meters in a whole hurricane," she explains.

    That makes no sense at all. A cloud is very little like a hurricane except that it involves water, air, and differentials of temperature and pressure.

  • by NASAKnight ( 588155 ) on Thursday September 04, 2003 @02:05AM (#6866328) Homepage Journal
    Doesn't anybody know that elephants are non-standard units? Give me something I can work with here, people. How many library of congresses would it take to equal the weight of a storm cloud?

  • by Fatllama ( 17980 ) on Thursday September 04, 2003 @02:06AM (#6866339) Homepage
    ... the cloud is a witch! No wait, ducks not elephants. n/m
  • Target Audience? (Score:5, Insightful)

    by i_am_nitrogen ( 524475 ) on Thursday September 04, 2003 @02:06AM (#6866340) Homepage Journal
    Who on earth is this written for? It says at the bottom that at least two people contributed to the report. The language is like that of a 4th grader. Is this what all ABC News reports look and/or sound like?

    This makes the BBC seem like something written by Stephen Hawking.

    • by Tokerat ( 150341 )

      ...perhaps that's so it may be used in a 4th grade science class? Honestly, I don't think this is exactly hard-hitting journalism targeted at America's most prominent adult citizens...

      It's just a neat little factoid little Billy can print and bring to teacher for extra credit. Also, an interesting fact, if it's something you never considered before.
    • by morganjharvey ( 638479 ) on Thursday September 04, 2003 @02:59AM (#6866556)
      I guess that this is what they refer to as a "fluff" piece...
      I'll go away now...
  • by rblancarte ( 213492 ) on Thursday September 04, 2003 @02:07AM (#6866346) Homepage
    We are talking water. Water is very heavy. It is just that water in a cloud is in vapor form, and also floating in the sky that we sort of forget that it is still water.

    And to be honest, the numbers (200,000 elephants in a storm cloud) don't shock me. Think of the destruction caused by floods, which are caused by rain. In some ways, it makes sense.
    • by rew ( 6140 )
      Water in a cloud is no longer in vapor form. The water in the air below the cloud is generally in vapor form. It's transparent, as opposed to whitish when it's in small particles.

      The weight of the water in a unit of volume of air just below your standard cumulus cloud is about the same as the weight of the water-vapor in the could.

      Anyway, your standard cloud being 1km x 1km x 200m, the weight of the AIR in that cloud comes to 1.2 kg/m^3 * 1000*1000*200 / 1000 kg/tonne= 240 thousand tonnes. That should be
  • An earlier answer (Score:5, Informative)

    by staplegun ( 452753 ) on Thursday September 04, 2003 @02:08AM (#6866350) Homepage
    Cecil Adams answered [straightdope.com] this a few years back. Sure he uses 747's instead of elephants, but his answer is a bit more detailed.
  • Surprised (Score:5, Funny)

    by cyril3 ( 522783 ) on Thursday September 04, 2003 @02:09AM (#6866354)
    I'm surprised a meteorologist can get through a degree and on the job training and after all that be surprised just how much water there is in a hurricane.

    I wonder if she has ever considered just how hot is the sun. Wow, its hotter than all the space heaters that have ever been made turned on in the drying closet and you locked in for the whole weekend with only a bottle of soda and some salt crackers. Although by saturday night it would feel pretty much the same.

    • Interestingly, the surface of the sun is cooler (10,000 F) than some of the temperatures that we can create in a lab on earth.

      The core is in the tens of millions of degrees, so no challenge there.
  • by Jason1729 ( 561790 ) on Thursday September 04, 2003 @02:10AM (#6866359)
    They use elephant weights in the article to make it easier to visualize. A Hurricane is 40 million elephants. That's just so much easier to visualize than 240 million tons (cubic meters) of water.

    ProfQuotes [profquotes.com]
  • by raehl ( 609729 ) * <raehl311@NoSPam.yahoo.com> on Thursday September 04, 2003 @02:11AM (#6866361) Homepage
    I'd guess it weighs about as much as Vaporware.
  • by Ironix ( 165274 ) <steffen@nor g r en.ca> on Thursday September 04, 2003 @02:11AM (#6866364) Homepage
    Yes, and I have a car that weighs over 1 trillion fleas.

    Did I mention my laptop that must weigh over 50 field mice...
    • It took quite a lot of research, but I did find out how much a flea weighs. It is approximately one millionth of a pound, or .000001 pounds. So, 1 trillion times 1 millionth of a pound would be... 1,000,000 pounds! It's closer to weighing as much as one billion fleas.

  • How much does the internet weigh?

    How much would it weigh if it was made of water?

    How much does all the spam sent on the internet each day weigh?

    Is there any place big enough to store it?

    How much does the near vacuum in all the CRTs connected to the internet weigh?

    How many ergs are there in all the electrons flying at all the CRT's on earth at any one instant?

  • by tjstork ( 137384 ) <todd,bandrowsky&gmail,com> on Thursday September 04, 2003 @02:13AM (#6866373) Homepage Journal

    The real question is how many midgets does an elephant weigh? If have 48 midgets per elephant, and I have 600 elephants per cloud, then....

  • by questamor ( 653018 ) on Thursday September 04, 2003 @02:13AM (#6866376)
    Are they Metric or Imperial elephants?
  • No wonder (Score:5, Funny)

    by cyril3 ( 522783 ) on Thursday September 04, 2003 @02:14AM (#6866379)
    hurricanes are so destructive what with 200,000 elephants flying all over the place.
  • by Anonymous Coward
    From the article "That means the water in one hurricane weighs more than all the elephants on the planet. Perhaps even more than all the elephants that have ever lived on the planet."

    Assume an elephant generation is 50 years. Assume the average number of elephants in Africa at any one time is 100,000 (this will be way low historically). So, 40 million elephants are born in 400 generations, or only 20,000 years.

    So there's no way this atatement "more than all the elephants that have ever lived on the planet
  • Wow... (Score:5, Funny)

    by DCowern ( 182668 ) * on Thursday September 04, 2003 @02:15AM (#6866382) Homepage

    This opens up a whole new world of "your mom" jokes... "Your mom weighs as much as a cloud." How many people are gonna be able to figure that one out? :-D

    • That's the beauty of it, if he doesn't get it, then he'll just be confused. If he does get it then he is a Slashdotter or a meteorologist and you'll have a whole lot more ammunition to mock him with.
  • Weigh? Forget weight! How much does one cost? I wouldn't mind having my own cumulonimbus hanging around.
  • by Chuck Chunder ( 21021 ) on Thursday September 04, 2003 @02:15AM (#6866385) Homepage Journal
    Sure, it can do easy conversions like 1 pint in decilitres [google.com].

    But can it do 1 cloud in elephants [google.com]? No!

    Perhaps Google isn't god after all.
  • Why do clouds float? (Score:4, Informative)

    by Aaron England ( 681534 ) on Thursday September 04, 2003 @02:16AM (#6866389)
    Clouds are composed primarily of small water droplets and, if it's cold enough, ice crystals. The vast majority of clouds you see contain droplets and/or crystals that are too small to have any appreciable fall velocity. So the particles continue to float with the surrounding air. For an analogy closer to the ground, think of tiny dust particles that, when viewed against a shaft of sunlight, appear to float in the air. Indeed, the distance from the center of a typical water droplet to its edge--its radius--ranges from a few microns (thousandths of a millimeter) to a few tens of microns (ice crystals are often a bit larger). And the speed with which any object falls is related to its mass and surface area--which is why a feather falls more slowly than a pebble of the same weight. For particles that are roughly spherical, mass is proportional to the radius cubed (r3); the downward-facing surface area of such a particle is proportional to the radius squared (r2). Thus, as a tiny water droplet grows, its mass becomes more important than its shape and the droplet falls faster. Even a large droplet having a radius of 100 microns has a fall velocity of only about 27 centimeters per second (cm/s). And because ice crystals have more irregular shapes, their fall velocities are relatively smaller. Upward vertical motions, or updrafts, in the atmosphere also contribute to the floating appearance of clouds by offsetting the small fall velocities of their constituent particles. Clouds generally form, survive and grow in air that is moving upward. Rising air expands as the pressure on it decreases, and that expansion into thinner, high-altitude air causes cooling. Enough cooling eventually makes water vapor condense, which contributes to the survival and growth of the clouds. Stratiform clouds (those producing steady rain) typically form in an environment with widespread but weak upward motion (say, a few cm/s); convective clouds (those causing showers and thunderstorms) are associated with updrafts that exceed a few meters per second. In both cases, though, the atmospheric ascent is sufficient to negate the small fall velocities of cloud particles. Another way to illustrate the relative lightness of clouds is to compare the total mass of a cloud to the mass of the air in which it resides. Consider a hypothetical but typical small cloud at an altitude of 10,000 feet, comprising one cubic kilometer and having a liquid water content of 1.0 gram per cubic meter. The total mass of the cloud particles is about 1 million kilograms, which is roughly equivalent to the weight of 500 automobiles. But the total mass of the air in that same cubic kilometer is about 1 billion kilograms--1,000 times heavier than the liquid! So, even though typical clouds do contain a lot of water, this water is spread out for miles in the form of tiny water droplets or crystals, which are so small that the effect of gravity on them is negligible. Thus, from our vantage on the ground, clouds seem to float in the sky.
  • by StewedSquirrel ( 574170 ) on Thursday September 04, 2003 @02:17AM (#6866391)
    Perhaps a more accurate method would be to extrapolate from the amount of water actually present in a cloud. A "cloud" isn't some well-defined object containing a set density of water. I'm sure a big puffy white one has a LOT less water than a big mean dark one that is the same size.

    Then again, when we're talking about clouds... they're just concentrations of moisture that happen to refract and reflect visible light. The air has moisture everywhere. What exactly is the difference in moisture content between a cloud and a "really wet day" in the jungle?

    I've seen it rain with very little cloud cover... So while we're at it, why not just weigh the air?

    Or we could get around to other even more pointless activities... ANYTHING to get you on /. :-)

    • Cloudless Skies (Score:2, Interesting)

      by chiasmus1 ( 654565 )
      I've seen it rain with very little cloud cover... So while we're at it, why not just weigh the air?

      Here in Japan it gets so humid that sometimes it rains without any clouds in the sky. I have always thought that was interesting.

  • by henriksh ( 683138 ) <hsh@freecode.dk> on Thursday September 04, 2003 @02:18AM (#6866399) Homepage
    I, for one, welcome our new meteorologist overlords!
  • How about in volkswagen beetles?
  • Since it is "floating in thin air", it has to be "lighter than air", wouldn't it? This would be the same principle that makes any boat "lighter than water" even though it might weigh thousands of tons.

    And of course a condensed cloud would be prety heavy. You could compress any /.'er down to the size of a pinhead, and he/she(/I) would be pretty heavy compared to any other pinhead.

  • ...isn't how much water in a cloud...

    ....rather how much vapor is in FWB Software [fwb.com]?

    (Mods, be gentle...)
  • by cra ( 172225 ) on Thursday September 04, 2003 @02:48AM (#6866503) Homepage
    I couldn't resist. To hell with karma. . .
  • Hmmm, let me see if I can get this right.
    Clouds are water vapor (duh).
    Water is H2O... which means the molecule has 8 protons for O, and 2 for the H's, a "weight" of 12.

    The majority of the atmosphere is N2, which has a total weight of 14. Thus, air containing water vapor is actually *lighter* than air without water vapor.

    How can you say a cloud weighs more than all the elephants in the world, if it actually weighs less than air?
  • <grammar nazi hat on>
    Is that what professionial journalism has come to?

    The thought of a hundred elephants-worth of water suspended in the sky begs another question -- what keeps it up there?

    Why must people keep abusing the phrase, "begs the question?" [2blowhards.com] It does not mean "causes us to question" or "makes me wonder." Just because MANY people keep making the same mistake does not make it so.
    </grammar nazo>

  • Peggy LeMone, senior scientist at the National Center for Atmospheric Research in Boulder, Colorado, did the numbers.

    Ah... only in The People's Republic of Boulder do people actually try to figure the weight of clouds.

    (Probably only Coloradoans will get it. Fuck the rest of you :))
  • This reminds me of the idea of replacing the SI system by the unit vole system. A vole would be kept in a special cage at Paris. The unit of mass would be its mass, the unit of length its length (over tail for preference) and the unit of power the energy it put into running round the treadmill, if that's what voles do.

    Of course the units would constantly change according to the state of health etc. of the vole, so all the energy devoted to stock market speculation could be rediverted to betting on commodit

    • I like the idea of a vole system. Of course we would have to define the standard vole to make it useful.

      Measurement systems need to have some relevance to the everyday world. Just look at the metric system, they based the length of the meter on a bad measurement of the size of the Earth, an otherwise insignificant planet. Things went downhill from there. We could have done just as well by digging up an old king and measuring the length of his forearm.

      Imagine that you are shipwrecked on a previously undi

  • by Infensus ( 640727 ) on Thursday September 04, 2003 @03:18AM (#6866619)
    Try skydiving trough a cloud. The do indeed look fluffy and soft from an airplane, but when you fall trough them at 200-280kmh, it feels quite different.. All those small droplets hitting your bare skin feels like hundreds or thousands of small nails, and larger drops can be be painful trough thin clothing as well..
    Not to mention hail within clouds. Hail is really, really painful. Skydivers really don't like hail. At all.
  • What about flying elephants?

    Or are these reports written by a bunch of dumbos?
  • The thought of a hundred elephants-worth of water suspended in the sky begs another question -- what keeps it up there?

    "First of all, the water isn't in elephant sized particles, it's in tiny tiny tiny particles," explains LeMone.

    Ah, I see. So if I cut something heavy into lots of different pieces, I can make it float.

    Weight is such a silly concept to even be discussing when it comes to clouds. It would be like weighing yourself underwater and listing that as your true weight.

  • by cca93014 ( 466820 )
    A cloud weigh the same as a sheep without any legs.
  • The enerrgy consumed by a 250W computer over a year is an equivalent of 87.6 micrograms.
  • -So, if it weighs as much as an elephant, it is made of ivory
    Bedevere : And therefore ?
    -A piano !!!
  • by DataCannibal ( 181369 ) on Thursday September 04, 2003 @04:37AM (#6866834) Journal
    Has anyone converted these figures into units we Brits can understand. Normally area here is expressed as multiples of the area of Wales (Jack Straw, the foreign secretary, uses this a lot). For smaller areas we use the Football (Soccer) pitch. Volume is a bit trickier as there is not a fixed unit but the volume of something is described by how many of the relevant objects would be needed to fill the Albert Hall. As for weight we need it as multiples of the England Pack (That's the eight guys in the scrum for you non-rugby players). So come on british mathematicians, your country needs you. How many England Packs does a typical raincloud over Lords Cricket Ground weigh, how many of them would be need to fill the Albert Hall and what fraction of the area of Wales would it cover ?
  • by neglige ( 641101 ) on Thursday September 04, 2003 @05:50AM (#6867012)
    Seems like nobody mentioned this before. Here [noaa.gov] seems to be a better source for the answer.
  • Ridiculous (Score:3, Interesting)

    by WebMasterJoe ( 253077 ) <joe@@@joestoner...com> on Thursday September 04, 2003 @09:19AM (#6867954) Homepage Journal
    We're measuring the weight of clouds? Come on, how about the mass? And the density? ...And I guess the volume, just to round out that formula. The density of a cloud is very very low, less than the air around it (which is why it floats). The article is just a piece of pop science - useful trivia if you're trying to impress drunks at a frat party, but not the sort of thing intelligent people want to start their mornings with.

    But it did get me thinking - since the clouds are less dense than air, there is less mass per cubic foot (or meter or whatever), so is the air pressure under a cloud lower? I know low pressure is indicative of a warm/cold front; are the two related?

How many NASA managers does it take to screw in a lightbulb? "That's a known problem... don't worry about it."