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Author Topic: Are radio stations causing global warming?  (Read 2967 times)

Offline traveler

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Are radio stations causing global warming?
« on: 30/06/2010 15:32:08 »
I've had this idea for a while and am wondering if it makes sense to anyone else. It is not just limited to radio stations, but to any transmitting device. Cell phones, radar towers TV stations, VHF/UHF radios, micro wave transmitters, WIFI and many other devices all send out huge amounts of power. My theory is that all of these waves must interact with water molecules in the air. Just like in a microwave oven, these water molecules must heat up when these waves pass through them. It is probably just a miniscule amount but if it is multiplied by the amount of energy being transmitted, it might add up to a significant amount of heat. To complicate this even further, the more heat = more water vapor. This looks like it would result in a cycle that compounds on itself.
 This would not be the total cause of global warming, just a significant additional factor.

 Does this make sense to anyone?


 

Offline Bored chemist

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Are radio stations causing global warming?
« Reply #1 on: 30/06/2010 19:53:31 »
"I've had this idea for a while and am wondering if it makes sense to anyone else. "
No.

How many radio stations need their own power station?

Does your car slow down when you turn the CB radio to transmit?

Does your mobile 'phone charger account for a significant fraction of your electricity bill?

The power used (never mind delivered) by all these transmitters is tiny. There must be some effect, but it's not significant in any way.
 

Offline SeanB

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Are radio stations causing global warming?
« Reply #2 on: 30/06/2010 20:55:45 »
Consider the case of a US radio station, transmitting 500kW ERP to it's coverage area. That will be approximately around the whole continental US, around 9.6 million square km ( from Wolframalpha, a very nice thing to use for out of the box queries, try it at www.wolframalpha.com ) so the power is around 51 milliwats per square kilometer, averaged over the coverage area.

Compare this to the solar irradiation during the day, at around 2kW per square meter, around 40 trillion times bigger (4e13 times bigger). There are hundreds of radio stations across the world, while thay may cause some local changes from the power plants that power them and the waste heat they give off ( funny thing is the new digital transmitters are very inefficient, compared to the old ones, as they have to both transmit at full power at all times as well as having a lower efficiency overall) but this is around the same effect as an urban heat island.

Radio transmitters are very insignifigant, as far as power consumption is concerned, as each one serves millions of people, and AM radio can be heard worldwide using the cheapest and simplest of receiver. THey are probably the most energy efficient mass media around, nothing physical is moved, and the individual listener has no need for complex ( expensive to maintain) infrastructure in most cases.

 

Offline Geezer

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Are radio stations causing global warming?
« Reply #3 on: 01/07/2010 03:48:02 »
at around 2kW per square meter, around 40 trillion times bigger (4e13 times bigger).


Erm, I think I detect a slight problem  ;D

2,000 W is only about 40,000 times greater than 0.05 W

Mind you, it's still a very big difference.
 

Offline Bored chemist

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Are radio stations causing global warming?
« Reply #4 on: 01/07/2010 06:53:50 »
at around 2kW per square meter, around 40 trillion times bigger (4e13 times bigger).


Erm, I think I detect a slight problem  ;D

2,000 W is only about 40,000 times greater than 0.05 W

Mind you, it's still a very big difference.
at around 2kW per square meter, around 40 trillion times bigger (4e13 times bigger).


Erm, I think I detect a slight problem  ;D

2,000 W is only about 40,000 times greater than 0.05 W

Mind you, it's still a very big difference.
A square kilometre is a bit bigger than a square metre.
I think it's about 40 billion fold more sun than radio.
« Last Edit: 01/07/2010 06:55:59 by Bored chemist »
 

Offline Geezer

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Are radio stations causing global warming?
« Reply #5 on: 01/07/2010 07:41:40 »
A square kilometre is a bit bigger than a square metre.

That could make a slight difference too.

EDIT: Bugger Bummer. So I missed about six orders of magnitude! What's the big deal?
« Last Edit: 01/07/2010 08:15:54 by Geezer »
 

Offline SeanB

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Are radio stations causing global warming?
« Reply #6 on: 01/07/2010 19:06:15 »
Geezer, talk to NASA about that, they crashed a few perfectly good space probes because one side said metre and the other side thought foot.

 

Offline syhprum

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Are radio stations causing global warming?
« Reply #7 on: 02/07/2010 10:38:12 »
Also confusion arises because of the use of ERP, this measurement takes into effect the antenna gain and is irrelevant to thermal effects.
The TV station with an ERP of 500kW may well be only emitting 20kW of actual power.
I checked the power consumption of my mobile phone charger (reputed to be ruining the planet) it is initially 4.3 W dropping to 0.3 W when the battery is charged. 
« Last Edit: 02/07/2010 10:42:32 by syhprum »
 

Offline FuzzyUK

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Are radio stations causing global warming?
« Reply #8 on: 22/07/2010 23:17:11 »
I've had this idea for a while and am wondering if it makes sense to anyone else. It is not just limited to radio stations, but to any transmitting device. Cell phones, radar towers TV stations, VHF/UHF radios, micro wave transmitters, WIFI and many other devices all send out huge amounts of power. My theory is that all of these waves must interact with water molecules in the air. Just like in a microwave oven, these water molecules must heat up when these waves pass through them.

If radio waves pass through them (water molecules), then they are not getting absorbed - so they are not heating the water. Generally speaking, it's only the extremely higher frequencies (microwaves) that interact with water. For instance, radar relies on back scatter from moist clouds to produce meaningful weather charts. Lower frequencies including frequencies even at VHF barely get absorbed by water.
 

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Are radio stations causing global warming?
« Reply #8 on: 22/07/2010 23:17:11 »

 

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