APOD: Global Warming Predictions (2009 April 21)

[Chris Peterson]

So let's get it straight.... CO2 causes warming, but the entire northern hemisphere is just emerging from one of the coldest, longest winters ever....

I just don't get how so many people are unable to grasp the difference between global climate and regional weather. It isn't a very difficult concept.

(BTW, where I live in the central U.S., this was a short, warm, dry winter. So it isn't "the entire northern hemisphere".)

[rstevenson]

Granlund wrote: So let's get it straight.... CO2 causes warming, but the entire northern hemisphere is just emerging from one of the coldest, longest winters ever....

And your source for this extraordinary claim is ... ?

Rob

[bystander]

So let's get it straight.... CO2 causes warming,

Greenhouse gases do not cause warming, they trap the heat from solar radiation. Water vapor has much more impact on the greenhouse effect than does carbon dioxide. Maybe we should cover the seas with reflective shields to reduce evaporation. The one gas that has the most potential for runaway greenhouse effect is methane from the Artic permafrost and clathrates buried in the seabeds.

[The Code]

Then all the plankton dies,, as do the rest of the life in the sea... good idea tho bystander

mark

[BMAONE23]

Greenhouse gases do not cause warming, they trap the heat from solar radiation.

I don't quite understand your statement above Isn't it the "Trapping of Heat" that causes warming? And then If the Greenhouse Gasses trap heat doesn't this Trapped Heat increase ambient temperatures?

@Hydro...
I'm still reading through your links 255 pages will take a while to ingest

[Chris Peterson]

Greenhouse gases do not cause warming, they trap the heat from solar radiation.

I don't quite understand your statement above Isn't it the "Trapping of Heat" that causes warming? And then If the Greenhouse Gasses trap heat doesn't this Trapped Heat increase ambient temperatures?

Semantics...

I think he was just being overly precise. It wouldn't be necessary if there weren't people arguing against global warming by claiming that only the Sun causes heating.

[bystander]

I don't quite understand your statement above Isn't it the "Trapping of Heat" that causes warming? And then If the Greenhouse Gasses trap heat doesn't this Trapped Heat increase ambient temperatures?

Green house gases do not cause heating. Heat is a form of energy. The energy comes from the Sun. The green house gases just prevent it from being reradiated into space. They do not contribute any energy. Saying they caused the warming would be like saying a teapot causes the water to boil. It's just a container.

[hydroresearch]

Greenhouse gases do not cause warming, they trap the heat from solar radiation.

I don't quite understand your statement above Isn't it the "Trapping of Heat" that causes warming? And then If the Greenhouse Gasses trap heat doesn't this Trapped Heat increase ambient temperatures?

@Hydro...
I'm still reading through your links 255 pages will take a while to ingest

Thanks for considering it. I enjoy our discussions. Even though we may agree to disagree.

[aristarchusinexile]

Maybe we should cover the seas with reflective shields to reduce evaporation.

Bystander .. have you ever thought of working for a crude oil shipping company writing press releases: "The spill of 1,000 million gallons of heavy crude oil which is now covering 10,000 square miles of the Gulf of Mexico was orchestrated to reduce global warming through a descrease in oceanic evaporation in the blah blah blah ....."

[aristarchusinexile]

I don't quite understand your statement above Isn't it the "Trapping of Heat" that causes warming? And then If the Greenhouse Gasses trap heat doesn't this Trapped Heat increase ambient temperatures?

Green house gases do not cause heating. Heat is a form of energy. The energy comes from the Sun. The green house gases just prevent it from being reradiated into space. They do not contribute any energy.

Much Heat is also definitely generated by Babylon's unbridled commercial activity as well as the stunned-brain, greed laden mentality of earth's human population. And my "Much" quantity is regardless of solar input

[aristarchusinexile]

....of course there is a simple way to eliminate CO2... just kill every man woman and child on the earth.... and all the animals too. Oh... then all the plants would die too.

'If those days were not shortened all flesh on the earth would perish'.

[bystander]

Much Heat is also definitely generated by Babylon's unbridled commercial activity as well as the stunned-brain, greed laden mentality of earth's human population. And my "Much" quantity is regardless of solar input

Let's be clear, the vast majority of Earth's heat comes from the Sun. On a global scale, all other sources are negligible. If we moved the Earth out to the asteroid belt, the "Ice Ages" would look like a summer heat wave in Death Valley.

[Chris Peterson]

Much Heat is also definitely generated by Babylon's unbridled commercial activity as well as the stunned-brain, greed laden mentality of earth's human population. And my "Much" quantity is regardless of solar input

Let's be clear, the vast majority of Earth's heat comes from the Sun. On a global scale, all other sources are negligible. If we moved the Earth out to the asteroid belt, the "Ice Ages" would look like a summer heat wave in Death Valley.

Some numbers: the Earth absorbs from the Sun about 3e24 J/yr (it receives more); humans consume about 5e20 J/yr. If every bit of the energy produced by people was converted to heat (which, of course, it isn't), that's still just 1/6000 of the solar energy. I doubt we have the ability to even detect its effects on global temperatures.

Fun fact: since the human body radiates around 75W, if you look at the energy production of the entire human population from body heat alone, it works out to around 2e19 J/yr. There's some serious energy available there, if we could just harness it. (Wasn't that what the computer masters in The Matrix were doing?)

[BMAONE23]

I don't quite understand your statement above Isn't it the "Trapping of Heat" that causes warming? And then If the Greenhouse Gasses trap heat doesn't this Trapped Heat increase ambient temperatures?

Green house gases do not cause heating. Heat is a form of energy. The energy comes from the Sun. The green house gases just prevent it from being reradiated into space. They do not contribute any energy. Saying they caused the warming would be like saying a teapot causes the water to boil. It's just a container.

But the teapot is instrumental in allowing the water to reach the boiling point. Take away the teapot, and the water will extinguish the fire.

Take away the gasses that trap heat, and solar heat gets radiated back to space. So the Sun can't cause global warming because it doesn't create the effect of trapping solar radiation in the atmosphere. It only supplies heat.

[BMAONE23]

Much Heat is also definitely generated by Babylon's unbridled commercial activity as well as the stunned-brain, greed laden mentality of earth's human population. And my "Much" quantity is regardless of solar input

Let's be clear, the vast majority of Earth's heat comes from the Sun. On a global scale, all other sources are negligible. If we moved the Earth out to the asteroid belt, the "Ice Ages" would look like a summer heat wave in Death Valley.

You are absolutely correct. Your statement would also imply that Global Warming isn't caused by the addition of heat (since solar iradiance only changes be a factor of 1/10,000 between solar cycles and man made heat sources only have the total combined energy of perhaps 1/100,000 the solar output or less) but is rather caused by the trapping of heat causing a backfeed loop in the process. The same principal is how a teapot works so effectively. Water boils faster in a teapot than it does in an open pan because the teapot is a closed loop system which doesn't allow heat to escape.

[aristarchusinexile]

Fun fact: since the human body radiates around 75W, if you look at the energy production of the entire human population from body heat alone, it works out to around 2e19 J/yr. There's some serious energy available there, if we could just harness it. (Wasn't that what the computer masters in The Matrix were doing?)

Good stuff, Chris. Thanks.

[aristarchusinexile]

Much Heat is also definitely generated by Babylon's unbridled commercial activity as well as the stunned-brain, greed laden mentality of earth's human population. And my "Much" quantity is regardless of solar input

Let's be clear, the vast majority of Earth's heat comes from the Sun. On a global scale, all other sources are negligible. If we moved the Earth out to the asteroid belt, the "Ice Ages" would look like a summer heat wave in Death Valley.

But .. mankind's heat is generated and (generally) retained at lower levels. It's effect is more localized.

[neufer]

Fun fact: since the human body radiates around 75W, if you look at the energy production of the entire human population from body heat alone, it works out to around 2e19 J/yr. There's some serious energy available there, if we could just harness it.

Rather...we need Family Planning to limit all those Family Joules.

[hydroresearch]

Fun fact: since the human body radiates around 75W, if you look at the energy production of the entire human population from body heat alone, it works out to around 2e19 J/yr. There's some serious energy available there, if we could just harness it.

Rather...we need Family Planning to limit all those Family Joules.

Here is another fun fact. The term greenhouse warming is really a misnomer as the temperature increase in a greenhouse is caused by the glass inhibiting convection of the air and not the trapping of long wave radiation.

[Chris Peterson]

But .. mankind's heat is generated and (generally) retained at lower levels. It's effect is more localized.

Not really. The values I used for the energy from the Sun were just for what was absorbed by the ground and oceans. I ignored the energy absorbed by the atmosphere.

There may be highly localized temperature effects from human activities, but that is a drop in the bucket from a global temperature perspective.

[Chris Peterson]

Here is another fun fact. The term greenhouse warming is really a misnomer as the temperature increase in a greenhouse is caused by the glass inhibiting convection of the air and not the trapping of long wave radiation.

That is part of the mechanism for heating inside a greenhouse. The other part is the selective transmission of the glass or plastic walls. These transmit visible light, which is converted to longer wavelength radiation when absorbed by plants and interior surfaces, and which does not efficiently reradiate through the walls because they are moderately opaque to long wavelengths. Reduced convection is not essential to greenhouse function; selective transmission of the windows is.

So the term "greenhouse effect" is perfectly reasonable, both for describing greenhouses as well as describing one of the simpler components of Earth's energy balance.

[BMAONE23]

It also accurately describes a process where the heat is supplied but temperatures only rise because it is trapped in an environment. Temperatures don't rise in a Greenhouse because the sun gets hotter adding more heat. Temperatures rise because the glass/plastic panels effectively trap it in the Greenhouse Ecosystem and hinder it from reradiating outside the Greenhouse Ecosystem. Much like the greenhouse gasses effectivly trap the heat inside the Earth Ecosystem and hinder its reradiation to outside the Earth Ecosystem.

[BMAONE23]

The Teapot is actually a pretty good experiment to demonstrate this.
You will need a measuring cup,
A teapot
A 2qt saucepan
a candy thermometer
a stopwatch/digital timer
Fill a teapot with water (about 6 cups of water). Pour the water into a 2qt saucepan (Just about to the brim?) Fill the teapot again. Let both water containers reach room temperature. Turn on a burner on your stove (setting doesn't matter as long as it is constant...like the sun) plact the teapot on the burner and start the stopwatch/timer. When the teapot start whisteling remove it from the heat (leave the burner on) and note the time taken. Take the water temp with the candy themometer. Write down the temperature and time.
Now place the saucepan on the heat and time how long it takes for the water to reach the same temperature at that in the teapot was.
Which reached boiling temperatures faster???


You will notice that the water in the teapot boiled faster.


The burner represents the Sun adding heat to the atmosphere.
The water represents the earth's atmosphere absorbing and reradiating heat.
The open Saucepan represents minute ammounts of greenhouse gasses blocking heats retransmission to space.
The Teapot represents greater ammounts of heat blocking gasses (More worst case than anything else because it represents a near total block) But it does simulate a blocking mechanism.

[hydroresearch]

Here is another fun fact. The term greenhouse warming is really a misnomer as the temperature increase in a greenhouse is caused by the glass inhibiting convection of the air and not the trapping of long wave radiation.

That is part of the mechanism for heating inside a greenhouse. The other part is the selective transmission of the glass or plastic walls. These transmit visible light, which is converted to longer wavelength radiation when absorbed by plants and interior surfaces, and which does not efficiently reradiate through the walls because they are moderately opaque to long wavelengths. Reduced convection is not essential to greenhouse function; selective transmission of the windows is.

So the term "greenhouse effect" is perfectly reasonable, both for describing greenhouses as well as describing one of the simpler components of Earth's energy balance.

Sorry Chris but you are dead wrong on this one. A study done in the 60's (I'll get you the reference) showed 2 greenhouses, one with regular glass, the other with an opaque material which was transparent to long wave radiation. The result, the ambient temperatures where within the measurement error!

[Chris Peterson]

Sorry Chris but you are dead wrong on this one. A study done in the 60's (I'll get you the reference) showed 2 greenhouses, one with regular glass, the other with an opaque material which was transparent to long wave radiation. The result, the ambient temperatures where within the measurement error!

I'm not buying it.

Could you please stop quoting yourself? It makes it difficult to respond, or to even tell when you've said something new. The quote tags should only go around previous material you are responding to.