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Cities' Heat Can Affect Temperatures 1000+ Miles Away

Posted by timothy on 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."

5 of 263 comments (clear)

  1. Not 1609 kilometers... by Anonymous Coward · · Score: 5, Informative

    more than 1,000 miles away (1609 kilometers)

    Seriously, if you have one rough rounded number you can't do an exact convert and add false precision to the statement...

    1. Re:Not 1609 kilometers... by Genda · · Score: 5, Interesting

      I took chemistry a long time ago. The teacher said if you turn in dissociation constants with more than two decimal places, he'd mark them wrong (for those students who did their calculations on digital devices and copied all 10 digits of result.) He explained that these were chaotic events and everything past the second digit was noise.

      I think the point of the very specific number above is simply it being a single data point. In fact heat effects may travel tremendously further than even that. More important, if heat is shifting the jet stream, secondary and tertiary effects may be happening downstream many thousands of miles and include drought, flood, or unseasonable weather. As well, the city heat drives low altitude moisture and chemical particulates (soot and industrial dust) into the higher atmosphere (potentially punching a hole in the common inversion layers) and that moisture/nucleation may have significant down wind impacts as well. I'm looking forward to seeing what the models say. If we're lucky, the effect will be more cloud cover, increasing earth's albido, and be a thermal cooling factor over-all. If not, it may be adding to a climate that is growing ever more unstable and that's bad news for everyone.

      My question is, why isn't anyone talking about the air pollution problems happening this month in China? Air that's being called lethal by some, over 40x more polluted that world health limits recommend. Here's a story about a factory that burned for 3 hours because nobody could tell the difference between the smoke and the pall of smog. My greatest concern is that over the last ten years there have been several events of smog from China reaching the western U.S., this being the worst smog event in remembrance, there is a real chance it could make it to America. Thankfully, it winter and most likely will be washed into the sea by storm systems. Had this been summer we would certainly be facing serious environmental threat. So why isn't this a HUGE conversation right now, virtually nobody is even talking about it.

    2. Re:Not 1609 kilometers... by smittyoneeach · · Score: 5, Insightful

      The environment is only a major issue during a Republican administration.

      --
      Get thee glass eyes, and, like a scurvy politician, seem to see things thou dost not.--King Lear
  2. Glider pilots already knew this by sciencewatcher · · Score: 5, Interesting

    Serious, first thing to look for a thermal is the local town, absent mountains or hills. A large parking lot already does do fine. I know of a military airport which has a cemetary nearby, the dense black marble is sufficient.

  3. Fear, uncertainty, and doubt by Sockatume · · Score: 5, Insightful

    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.

    --
    No kidding!!! What do you say at this point?