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Earth Science

Cities' Heat Can Affect Temperatures 1000+ Miles Away 263

Posted by timothy
from the let's-terraform-earth dept.
Living in dense cities makes for certain efficiencies: being able to walk or take mass transit to work, living in buildings with (at least potentially) efficient HVAC systems, and more. That's why cities have been lauded in recent years for their (relatively) low environmental impact. But it seems at least one aspect of city life has an environmental effect felt at extreme distances from the cities themselves: waste heat. All those tightly packed sources of heat, from cars to banks of AC units, result in temperature changes not just directly (and locally) but by affecting weather systems surrounding the source city. From the article: "The released heat is changing temperatures in areas more than 1,000 miles away (1609 kilometers). It is warming parts of North America by about 1 degree Fahrenheit (0.6 degrees Celsius) and northern Asia by as much as 1.8 degrees Fahrenheit (1 degree Celsius), while cooling areas of Europe by a similar amount, scientists report in the journal Nature Climate Change. The released heat (dubbed waste heat), it seems, is changing atmospheric circulation, including jet streams — powerful narrow currents of wind that blow from west to east and north to south in the upper atmosphere. This impact on regional temperatures may explain a climate puzzle of sorts: why some areas are having warmer winters than predicted by climate models, the researchers said. In turn, the results suggest this phenomenon should be accounted for in models forecasting global warming."
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Cities' Heat Can Affect Temperatures 1000+ Miles Away

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  • by Jane Q. Public (1010737) on Monday January 28, 2013 @04:37AM (#42713465)
    ... But this directly contradicts those greenhouse-gas warming models that assume that the "heat island" effect is of little or no significance. To the best of my knowledge, that is the majority of them.
  • by Anonymous Coward on Monday January 28, 2013 @04:48AM (#42713513)

    How do you know that it is rounded?

  • by maxwell demon (590494) on Monday January 28, 2013 @05:00AM (#42713549) Journal

    It says "more than", and it is obvious from context that it doesn't exclude an effect for less than 1000 miles (actually, the absolute biggest effect of a city is at 0 miles distance for sure). Therefore it cannot be an exact number.

    Also, how probable is it that a natural phenomenon agrees to four significant digits with a completely arbitrary length unit not based on that phenomenon?

  • by Anonymous Coward on Monday January 28, 2013 @05:05AM (#42713557)

    Not really. The overall temperature difference is the same. This is just affecting how the change is distributed. It's notable, and explains a known issue with the models, but it doesn't in any way invalidate the overall predictions, i.e., things are getting warmer.

    Seriously, the entire waste heat production of humanity is nothing compared to solar heating. Solar heating is ~170 petawatts. The total energy production of humanity isn't even a tenth of a percent of that. Closer to a hundredth of a percent, really.

  • by SuricouRaven (1897204) on Monday January 28, 2013 @05:12AM (#42713593)

    The heat island effect has always been taken into account for purposes of observation - when some of your data points are located in cities, you need to either discard them or compensate in some manner. This study shows that the effect covers a far wider area than previously thought. A few minor revisions to the models are needed. That doesn't mean previous predictions are suddenly all wrong - just that they are not as accurate as they will be once these revisions are implimented.

  • by dbIII (701233) on Monday January 28, 2013 @05:40AM (#42713677)
    This crap again? Astronomy fits that narrow "not a science" description as well. I dare you to walk up to Buzz Aldrin and tell him astronomy is not a science. This "debate" is on the same level as the moon landing deniers.
    Anyway, from what I've heard there are this things called digital computers (that thing you are using to convey your silly luddite drivel) that can model the theories of the climate scientists, and then the models can be compared with reality. This gives you those five steps.
  • by Bongo (13261) on Monday January 28, 2013 @06:17AM (#42713797)

    Well it is the details. Some claim it is "incontrovertible", "reality", and "truth", when part of what they're talking about is predictions/scenarios stretching 50 years into the future. Question it and they say "it is science!" like because science is so highly respected. And why do we respect science so much? Because it is so rigorous and self-correcting. But that sounds more like: make hypotheses; test hypothesis; correct; etc. steps. Ie what the other poster was quoting. So yeah we can call the field broadly a science, but there's always the question, what specific things did you do to arrive at this specific result?

    When the Chairman of the IPCC was asked, what about the scientists who disagree with the human caused catastrophic climate change scenario, he said to a public audience, there are still people who deny the Earth is flat. Now how does he go so easily to such an absolutist position?

    Is it science to label all your critics as holocaust deniers and superstitious infants from the dark ages?

    So it is healthy to remind ourselves, ok, the scientific method at its best has this rigorous checking, and if you're not doing that, perhaps because it is a very hard thing to check, like human diet, very hard to figure out what's healthy because you just can't experiment on people like lab rats keeping them in a cage and controlling all they eat for generations -- yet we're all told that nutrition is a science and we should take the experts seriously.

    The question is always, how do they know? What did they do to arrive at that result?

    Well the computer model says the plane is fine so let's just start building a production run and not bother with test pilots.

    A lot of stuff is called a science, and generally it is, but the real question is, how high are their standards of quality? If your objective is to study the music of people 6000 years ago, well you can make hypothesis, but as none of their music was written down, if you want to maintain a high standard, you'll have to just say, we have no idea what it sounded like.

    Claiming that your model is good for 100 years out when it is still hard to differentiate between it being correct and a lucky guess amongst a flock of simulation runs all with different parameters, and it sort seems to not be too far out today, compared to current climate, does not sound like a high standard.

    Asserting climate is the average of weather over the long term, again sounds wooly and not a high standard. It begs the question, why assume you can average the weather over the long term, eliminating chaotic effects? Where's your rigorous testing for that assertion?

  • by Sockatume (732728) on Monday January 28, 2013 @06:27AM (#42713831)

    It's a bit rich to go on about "the other top nations" refusing to join in when the US flatly refuses to join the climate change accords that the rest of the developed (and much of the developing) world have established.

  • by Viol8 (599362) on Monday January 28, 2013 @06:30AM (#42713841)

    Unfortunately tipping the balance is all that is required to mess it up.

  • by dbIII (701233) on Monday January 28, 2013 @06:44AM (#42713895)

    Question it and they say "it is science!"

    When questioned with PR company lies that answer is a fairly obvious response.
    When one "side" pretends that if the other is not omniscient then everything they say can be rejected and replaced with a handy PR lie that's when you get assertions of certainty in response. Certainty is possible in general terms even if unreasonable levels of precision is not.

    Where's your rigorous testing for that assertion?

    There is a website called "google scholar" now so there is no longer any reason to pretend there is no rigorous testing just because you can't be bothered to ever set foot in a library before making these wild claims. What is this bullshit about flooding the net with noise to try to shout down anyone with a clue? Do you realise that your anti-expert bullshit is having fallout in other fields, and if you are good at anything at all such a line is going to backfire on yourself if it catches on?

    Asserting climate is the average of weather over the long term, again sounds wooly and not a high standard

    I think it's about time to graduate from the childrens dictionary Bongo if you are attempting to be credible.

  • by Anonymous Coward on Monday January 28, 2013 @06:59AM (#42713939)

    It's a bit rich to go on about "the other top nations" refusing to join in when the US flatly refuses to join the climate change accords that the rest of the developed (and much of the developing) world have established.

    So what? Those accords haven't done jack shit in the past, they are largely a symbolic gesture and none of the nations who did agree to the last ones managed to live up to what they promised. You seem to think that not sitting down at a table in a room full of people is the same thing as doing nothing, which is about as far from the truth as is possible. There is a large and active environmental movement in the US, and we are actively taking steps to reduce emissions. Just because we're not willing to give up our sovereignty and bind ourselves to the whims of a foreign political body doesn't mean we are ignoring the problems.

    Meanwhile, as the parent already mentioned, China is pumping out a fucking shitload of pollution at an ever-increasing pace and all you dicks can do is say "But the US did something kind of like that 100 years ago!" Fuck off.

  • by Sockatume (732728) on Monday January 28, 2013 @07:04AM (#42713955)

    Perhaps if the US had been a participant in the previous efforts they would've been:

    1) Worth a damn scientifically
    2) Politically effective

    You can't decry other nations for failing to participate in the process, yet justify your own absence by saying the process is pointless.

  • by Sockatume (732728) on Monday January 28, 2013 @07:36AM (#42714047)

    Isn't this comment more or less an archetypal example? Veiled and nonspecific allusions to error, uncertainty, and weakness? No actual substance? Nonspecific accusations that could be leveled at any piece of research? Let's look at the issues you raise.

    "The question is always, how do they know? What did they do to arrive at that result?"

    It's in the papers. And countless popular accounts.

    "...does not sound like a high standard."

    That's why your rhetorical scenario is not the standard to which climate science is held. If you're interested it's... in the papers, and in the countless popular accounts.

    "Where's your rigorous testing for that assertion?"

    It's in the papers, and countless popular accounts. Assuming, of couse, you do not set an arbitrarily strict limit for "rigorous" that excludes them.

  • by smitty_one_each (243267) * on Monday January 28, 2013 @07:47AM (#42714071) Homepage Journal
    The environment is only a major issue during a Republican administration.
  • by LordLucless (582312) on Monday January 28, 2013 @08:40AM (#42714233)

    Something doesn't have to be scientific to be truth. Philosophy, history, mathematics - all have means of determining "truth" without relying on the scientific method. The problem is that "science" is increasingly taken to mean "rational", when that is not true - science is a subset of rationality. Stating something is not scientific is not necessarily an attack against it; it's purely descriptive.

  • by Sockatume (732728) on Monday January 28, 2013 @09:29AM (#42714425)

    Everything is veiled and nonspecific if you refuse to read it. Experimental science is not all science. What is your stance on evolution? History? Epidemiology?

  • by Jane Q. Public (1010737) on Monday January 28, 2013 @02:13PM (#42717437)

    "Not really. The overall temperature difference is the same."

    Yes, really. If the heat island effect is actually significant -- not to mention as strong as this article makes it out to be -- then it invalidates some pretty major assumptions in some models.

    Not only would it affect the heat distribution, TFA suggests that ciities are the source of some of the measured heat increase, as opposed to, for example, CO2.

    If the models are invalid, they are invalid. It isn't enough to be okay with making decent short-term projections based on false assumptions. They the farther out the projection, odds are the farther they would be off.

No problem is so large it can't be fit in somewhere.