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New Map Shows USA's Quietest Places
sciencehabit writes Based on 1.5 million hours of acoustical monitoring from places as remote as Dinosaur National Monument in Utah and as urban as New York City, scientists have created a map of noise levels across the country on an average summer day. After feeding acoustic data into a computer algorithm, the researchers modeled sound levels across the country including variables such as air and street traffic. Deep blue regions, such as Yellowstone National Park in Wyoming and the Great Sand Dunes National Park in Colorado, have background noise levels lower than 20 decibels — a silence likely as deep as before European colonization, researchers say. That's orders of magnitude quieter than most cities, where noise levels average 50-60 decibels. The National Park Service is using the map to identify places where human-made noise is affecting wildlife.
I'd like to spend my entire life in ... BTW does it have an internet connection?
The quietest place I've ever been is Wilderness State Park in Michigan in the fall. No wildlife, an extremely quiet white noise coming from the lake - it was strange. Bryce Canyon was pretty quiet, too, but Wilderness is strikingly quiet. It's also a "dark sky park" so the stars at night are phenomenal.
My Other Computer Is A Data General Nova III.
Where we are is pretty deep blue on the map but I bet it is even bluer in reality as we are in a valley surrounded by mountains that lift the sound up over us providing an extra buffer. Loving it in the deep blue.
Interesting to note the map also looks like the city lights maps.
I'm a part-time musician and audio engineer. Because of this, I have a more sensitive perception of noise than probably most people. I have lived in urban/suburban areas most of my adult life and I can hardly stand it. Even quiet recording studios don't really get it as quiet as I'd like. I try to get out to the wilderness whenever I can which is every couple of months - I mean way out there where you will find very few people nearby. It is difficult to find words to describe how nice and peaceful it is when it's so quiet - not to hear noise of any kind, except from nature. We are surrounded by air-conditioning and cars, and people and civilization - and it frankly takes a toll on my sanity (the sound is all I'm talking about). Much to my wife's chagrin, I regularly wear earplugs to restaurants, and always carry them with me. It's really amazing how loud things are.
The summary is pretty much the entire contents of the linked article, except for a relatively low-resolution map of the US with colors indicating what's loud and quiet. You guessed it - cities are loud, wilderness is quiet.
The quietest part's, where she hasn't been..
http://xkcd.com/1138/
Just another heat map of the population. Nothing to see here, folks.
Great Sand Dunes is quiet in the summer because it's *HOT* there at that time of year.
If this map was generated for late spring it would show a different result.
Not that the obvious bias will prevent the Government idiots from basing all kinds of policies on it.
Decibels are measured on a logarithmic scale. 30 dB is an order of magnitude louder than 20 dB (10 times the power).
60db is only 1/3 of an order of magnitude above 20db. 200db is one order of magnitude above 20db and is like a canon going off and no city is that loud consistently. Two orders of magnitude above 20db would damage hearing at 2,000db.
You fail. db is a logarithmic scale. 10db is a factor of 10. 60db is 4 orders of magnitude from 20db.
Yes, but there's often a hell of a racket shortly after predator spots prey. And then there's sex, when one frog is croaking for a mate a fox can easily home in on it, when tens of thousands are doing it all at the same time even the fox's huge ears cannot pinpoint an individual frog unless it's almost standing on it. Disorientating predators with omni-directional noise is a common tactic for a variety of small critters. In certain years large green cicadas here in Oz fill the trees for a few weeks in summer, the high pitched noise can be that loud that it hurts your ears. There are millions of them each about the size of a man's thumb, making a huge racket, but spotting one in a tree takes a surprising amount of searching and luck.
Nature's noisy orgies are short and seasonal, for the rest of the year(s) between events the same location will be almost silent.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
well what do you know ....
that map looks exactly like a map of CITY LIGHTS
"I don't pitch OpenSUSE Linux to my friends, i let Microsoft do it for me
It's a log scale.. +3db is double the magnitude. So 20 to 60 is +40db which is about 13 doublings (40/3=39), or 8,192 times the original magnitude plus another 1/3 of a double which puts you almost exactly at 11,000 times the magnitude.
Engineers use db so you don't have to do all the multiplication and division to compare the numbers, you can just add and subtract. It harkens back to the days of slide rules where taking the log of a number was *easy* and then you could just add or subtract to multiply and divide.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Not only did you fail to know what decibels meant in terms of being logarithmic like others above pointed out, but the numbers you have are way off too. Being really close to a cannon is going to be on the order of 160-180 dB, unless your head is somewhere in the path of the projectile. You're not going to find constant sound at 200 dB without a special atmosphere on the surface of the Earth, as that requires a pressure wave greater than an atmosphere in pressure. Heck, shock-waves around 190 dB damage cement and brick walls, and can damage the heart and lungs and almost at the point of removing limbs... well beyond hearing damage. Close to the hypocenter of an airburst hydrogen bomb would only be on the order of 210-230 dB, and ~400 dB in the center of the bomb when detonating. 2000 dB would involve pressures 60 orders of magnitude higher than in a neutron star, so probably creating black holes, and is only about 20 orders of magnitude short of Planck scale.
It's a log scale.. +3db is double the magnitude. So 20 to 60 is +40db which is about 13 doublings (40/3=39), or 8,192 times the original magnitude plus another 1/3 of a double which puts you almost exactly at 11,000 times the magnitude.
Doubling is a tad over 3.01 db. Might not seem like much of a correction, but you some how managed to get "almost exactly 11,000" that should have been exactly 10,000...
Sounds like a plot to a classic 70s TV movie or an episode of one of those anthology shows. Got to have the protagonist cupping his ears, with a look of severe distress as non-stop quick shots of things making innocuous noises flash, interjected by the camera wildly pan-zooming his face.
Needs more cowbell.
Why isn't Alaska represented?
As other commenters have noticed, the map looks like a light map, a little TOO much like a light map.
At first I thought they actually HAD used a light map, just for the sake of illustration, but it clearly shows a legend in decibels.
Here is a light map from NASA: http://www.nasa.gov/sites/defa...
You will notice a few small but very bright dots in North Dakota. These are not cities, they are oil fields. They aren't nearly as loud as a city of comparable light output, yet they still show up as bright spots on the audio map.
I'm sure there are inconsistencies in other locations where the light and sound values should be different, but appear the same on both maps.
Yippppeeeeee for silence!
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Make sure you say Yippppeeeee!!!!! when you first-post.
You took a rather roundabout route to a somewhat inaccurate value of what 40dB meant.
The definition is that +10dB is 10 times the power. So +40dB is by definition 10000 times the power. 3dB is only approximately a doubling.
But that doesn't explain the figure you gave. A "third of a doubling" would mean multiplying by the cube root of 2 which would give an answer of about 10321, still somewhat off from the correct answer but substantially closer than the figure you gave.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
Your map is ready.
"I believe in Karma. That means I can do bad things to people all day long and I assume they deserve it." : Dogbert
The correlation with this map is telling.
http://eoimages.gsfc.nasa.gov/images/imagerecords/55000/55167/earth_lights_lrg.jpg
It's only that silent, because there's nobody there to hear the falling trees and shitting bears.
Wow. I never realized how loud it is all over Lake Michigan. I guess it's the noise from the water rippling, or noise from boats.
I understand why the places marked in blue and yellow are as shown. Why does the entire midwest have an orange color?
Yea.... My brain was messed up... After remembering that Decibels means 1/10th of a bel by definition, this means that +40DB is 10,000 (four zeros) by definition... This 3db is double thing is a short hand rule that is "close enough" for slide rule math and what I originally was taught to use when doing calculations like this.
So... given the problem with the rule of thumb approximation I used, I'm not going to try and defend the math that got me the wrong answer..
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Death Valley has: no flaura*, no fauna*, one road*.
*Yes, obviously, there are brine shrimp and microscopic organisms and the odd car. That being said, no trees, grasses are there to rustle in the rare winds 282 ft below sea level.
*** Don't be dull.***
In the summer all I hear is a bunch of assholes riding Harley Davidson motor cycles. I'd like to blow them all up. Have have a relaxing summer afternoon because these asshole feel the need to drive through town ever 20 minutes or so.
From the article: "...animals such bats and owls, whose ears are up to 20 decibels more sensitive than human ears..."
The human ear is at its best able to detect a sound pressure only just greater than that caused by the Brownian motion in the fluid of the inner ear. If it were any more sensitive than that it would suffer continuous white noise from this source. In the 1960s Rosen found that the Mabaan tribe of south-eastern Sudan had levels of hearing sensitivity that approached this limit. So bats and owls don't intrinsically have 20dB (10 times in terms of sound pressure) greater sensitivity than we do - if they did their hearing would be swamped by self noise (but they do hear in different frequency bands than us).
The reality is twofold: firstly most of us have wrecked our hearing (both physical and perceptual) due to the noisy environments we inhabit; and secondly, wild animals are paying constant attention to what is going on round them in order to survive but we don't pay anything like the same attention. Consequently, our effective threshold of hearing is higher, but that's just because we no longer use our full potential.
I've written about this extensively, e.g. http://wildsoundscape.co.uk/in...