Climate Sensitivity and timing

[skierinvermont]

We're in the same ballpark (or at least within an order of magnitude)

The calculations I used are

To melt 1 gram of ice requires 334 Joules of energy.

1 km3 of water weighs 1x10^15grams

therefore

it takes 3.34x10^17J to melt 1km3 of ice.

If we take the average:

for the last 30 years - 1,12892x10^20J

for the last 20 years - 1.93720x10^20J

for the last 10 years - 2.14094x10^20L

average since 2007 - 2.77860x10^20J

average since 2010 - 3.17968x10^20J

These seem to match with what PIOMAS has come up with.

Can you explain why you're putting seconds into you're calculations? Not trying to be snarky, i just don't understand, we're talking energy not power.

Another dinner out of town - this social stuff is distracting, but needs to be dealt with. I'll be back late tonight or tomorrow.

Terry

~1x10^20 is the number of Joules that are used to melt ice every year. I am simply converting this to Joules/year to Joules/second in order to find the number of Joules that go into melting ice per second (on average over the course of a year).

Now we must simply calculate the amount of surface warming that must occur globally to increase radiation to space by an equal rate. Surface warming of .0018C increases the rate of radiation to space by an equal quantity.

[TerryM]

Skier

Watt/m2 isn't a term used in my field. Is it the equivalent of a Watt year/m2 or a Watt hour/m2?

1 Joule = 1 Watt second, so a Watt hour = 3.6 x 10^3 Joules and a Watt year ~ 3.16 x 10^7 Joules

We're in the same ballpark with the calculation for Joules, perhaps if we make the even conversion to Watt seconds, then Watt hours or Watt years we'll be able to discuss how many sq. meters are being affected.

Would you accept >1 x 10^20 as both the Joules figure and the Watt second figure giving us >2.77 x 10^17 Watt hours and >3.16 x 10^13 Watt years?

I replaced your ~ with the > since we haven't been as low a 1 for a while, and the ice volume seems to be fairly closely following an exponential decline. It's possible that we'll end with a Gompertz curve, but I can't think of a reason for the melt to slow at this late date.

Terry

[skierinvermont]

Skier

Watt/m2 isn't a term used in my field. Is it the equivalent of a Watt year/m2 or a Watt hour/m2?

1 Joule = 1 Watt second, so a Watt hour = 3.6 x 10^3 Joules and a Watt year ~ 3.16 x 10^7 Joules

We're in the same ballpark with the calculation for Joules, perhaps if we make the even conversion to Watt seconds, then Watt hours or Watt years we'll be able to discuss how many sq. meters are being affected.

Would you accept >1 x 10^20 as both the Joules figure and the Watt second figure giving us >2.77 x 10^17 Watt hours and >3.16 x 10^13 Watt years?

I replaced your ~ with the > since we haven't been as low a 1 for a while, and the ice volume seems to be fairly closely following an exponential decline. It's possible that we'll end with a Gompertz curve, but I can't think of a reason for the melt to slow at this late date.

Terry

It isn't the same as a watt year or a watt hour. Watt years and what hours are units of energy. A what is a unit of power (a rate of energy).

>1X10^20 joules of energy are used to melt sea ice per year. Convert years into seconds and you have Joules per second, which is the same thing as a watt.

That is the average rate of energy used to melt sea ice on this planet. (1X10^20)/365/24/60/60 = 3.2X10^12 Joules per second

Now the question becomes how much would the temperature of the earth have to rise in order to increase the rate of energy escaping to space by an equal rate of energy as calculated above to be 3.2X10^12 Joules per second.

The answer is increasing the earth's surface temperature by .0018C would increase radiation to space by 3.2X10^12 Joules per second. Such an increase in surface temperature would successfully increase earth's emissions to space by 1X10^20 Joules per year, the same amount of energy you and I both agree currently goes into melting sea ice per year.

[Msalgado]

It makes sense to average it out for the duration of the ice melt to get a W/m^2 value so that you can compare how much of the forcing from GHG is going into melting the sea ice with the same units. However, the duration of the ice melt season is not the entire year. For most of the year ice is not melting at all so I don't believe it would be correct. There's also the consideration that the ice melt occurs during period when the NH is receiving levels of insolation higher than the annual average so as a percentage the amount of energy that goes into melting the sea ice would be lower.

I think the calculation Skier is attempting is too simplified for what he's trying to show. I'm not sure its going to change the end result as the numbers for sea ice volume may seem rather large but when compared to the volume of the ocean that absorbs SW radiation it is quite small. Its important to remember that the volume numbers only matter in context of the overall system and not simply because they are large numbers. The ocean as a whole absorbs far more energy than the amount that goes into melting sea ice.

[skierinvermont]

The cooling effect of net annual volume loss is not a spring or summer phenomenon and even if it were when it stops and that extra energy starts going into sensible heat, the earth has the entire year to radiate away the extra energy to reach equilibrium. The earth's surface would have to warm .0018C to successfully radiate away an extra 1X10^20 Joules in a year.

You are not understanding the mechanism which will cause warming. Warming will occur because net volume loss of ice cannot continue forever. If net volume loss in summer ceases, but continues at the same rate (300km3/year) in the other 10 months of the year, the cooling effect will be slightly reduced but not eliminated. Net volume loss is a year-round phenomenon, and even if it were not, the only effect it would have on the calculation is to reduce the annual cooling effect currently and thus decrease the warming effect that would occur when the net melt ceases.

I've thought about this quite a bit and am sure that I am right. What we are discussing is the 'heat in the pipeline' caused by the global energy imbalance of .9W/m2. Melting of sea ice only forms a tiny tiny fraction of this .9W/m2, while the rest is primarily ocean heat storage. The earth's temperature will need to increase by .3C to radiate away the energy that currently goes into warming the oceans and melting ice. That's .6C with feedbacks. .0018C of which will occur when sea ice stops melting (in all months). That's .004C with feedbacks.

[WeatherRusty]

Whatever absorbed energy the system takes in must be exactly balanced by a like energy being lost or the temperature will either rise or fall.

The melting of ice consumes energy without raising the temperature in the phase transition. Energy is used to break the tight molecular bonds forming the crystaline stucture of ice rather than adding to the kinetic energy of the water molecules.

If for a period of time, less ice is being melted, then this energy of fusion is instead absorbed by liquid water in the process raising it's temperature.

Thermal energy and electromagnetic energy are constantly flowing, never stationary, unless locked up in the formation of molecular bonds. Over time, the same amount of energy entering the water must be subsequently lost from the water or it's temperature will rise. This rise in temperature can melt more ice. This feedback process stops when either the input energy falls or the output energy rises to match the temperature of the water.

How much energy are we talking about? Well, skier has figured it out. Since the global energy budget is vastly larger than the relatively small energies involved in the fusion of water molecules in the arctic, from a purely radiative standpoint little impact is had on the global temperature. The impact is much larger regionally however, and those regional difference can spread out far beyond the limits of the arctic.

Just a thought. Milankovitch cycles also impose a small regional change to the energy budget. Yet this is enough of a change to plunge the northern hemisphere into an ice age and back out. Think about that.

[skierinvermont]

Whatever absorbed energy the system takes in must be exactly balanced by a like energy being lost or the temperature will either rise or fall.

The melting of ice consumes energy without raising the temperature in the phase transition. Energy is used to break the tight molecular bonds forming the crystaline stucture of ice rather than adding to the kinetic energy of the water molecules.

If for a period of time, less ice is being melted, then this energy of fusion is instead absorbed by liquid water in the process raising it's temperature.

Thermal energy and electromagnetic energy are constantly flowing, never stationary, unless locked up in the formation of molecular bonds. Over time, the same amount of energy entering the water must be subsequently lost from the water or it's temperature will rise. This rise in temperature can melt more ice. This feedback process stops when either the input energy falls or the output energy rises to match the temperature of the water.

How much energy are we talking about? Well, skier has figured it out. Since the global energy budget is vastly larger than the relatively small energies involved in the fusion of water molecules in the arctic, from a purely radiative standpoint little impact is had on the global temperature. The impact is much larger regionally however, and those regional difference can spread out far beyond the limits of the arctic.

Just a thought. Milankovitch cycles also impose a small regional change to the energy budget. Yet this is enough of a change to plunge the northern hemisphere into an ice age and back out. Think about that.

Glad we agree

And regarding Milankovitch cycles .. most of this is due to surface albedo change which I agree is a much more significant mechanism than the warming in the pipeline from melting sea ice, though some here are still exaggerating it.

And you are right that the global warming of .0018C (I left out a zero in my last post) would be concentrated in the arctic, perhaps leading to larger feedbacks than normal. I estimated with feedbacks that it would be .004C, but perhaps with feedbacks it would be .01C (a 6X feedback, instead of the normal 2X) because of the additional ice melt. Feedbacks to regional warming of the arctic may be very large, but they cannot be runaway feedbacks otherwise we would have witnessed an ice free arctic with CO2 concentrations under 300ppm. Arctic sea ice would not be a stable consistent phenomenon of the last 10,000+ years.

Again, all of these are tiny numbers less than one hundredth of a degree. The bigger issue in the arctic is not the warming that is being hidden by melting sea ice, it is the fact that melting sea ice reduces albedo.

I agree it is significant, but many here are continuing to overestimate that factor as well.

[WeatherRusty]

Glad we agree

And regarding Milankovitch cycles .. most of this is due to surface albedo change which I agree is a much more significant mechanism than the warming in the pipeline from melting sea ice, though some here are still exaggerating it.

And you are right that the global warming of .0018C (I left out a zero in my last post) would be concentrated in the arctic, perhaps leading to larger feedbacks than normal. I estimated with feedbacks that it would be .004C, but perhaps with feedbacks it would be .01C (a 6X feedback, instead of the normal 2X) because of the additional ice melt. Feedbacks to regional warming of the arctic may be very large, but they cannot be runaway feedbacks otherwise we would have witnessed an ice free arctic with CO2 concentrations under 300ppm. Arctic sea ice would not be a stable consistent phenomenon of the last 10,000+ years.

Again, all of these are tiny numbers less than one hundredth of a degree. The bigger issue in the arctic is not the warming that is being hidden by melting sea ice, it is the fact that melting sea ice reduces albedo.

I agree it is significant, but many here are continuing to overestimate that factor as well.

Doesn't this always come back to the importance of feedback? The change in albedo is a feedback to the very small radiative distribution changes.

The Earth's albedo is fundamental to the Stefan-Boltzmann equation which is our first order determanent of effective (blackbody) temperature.....followed by the atmospheric greenhouse effect which modifies surface temp above the effective temp.

CO2 has not been the first order cause of glaciation during the recent past (3 million years). It has acted as a feedback along with water vapor.

The distribution of solar energy falling on 70 to 80 degrees north latitude during summer has made all the difference in the complete melting or not of the previous winter's snowfall. The overall TSI doesn't change much at all, the portion falling seasonally upon the high latitudes does.

[skierinvermont]

Doesn't this always come back to the importance of feedback? The change in albedo is a feedback to the very small radiative distribution changes.

The Earth's albedo is fundamental to the Stefan-Boltzmann equation which is our first order determanent of effective (blackbody) temperature.....followed by the atmospheric greenhouse effect.

CO2 has not been the first order cause of glaciation during the recent past (3 million years). It has acted as a feedback along with water vapor.

The distribution of solar energy falling on 70 to 80 degrees north latitude during summer has made all the difference in the complete melting or not of the previous winter's snowfall. The overall TSI doesn't change much at all, the portion falling seasonally upon the high latitudes does.

Well we can go back to discussing albedo change if you like. I just want to make sure everybody's clear that even with near-runaway feedbacks (6X), the amount of energy that goes into melting ice is so trivial that it would take very little warming to radiate this energy away once melting stops. And actually you wouldn't get big feedbacks on sea ice because there would be almost no ice left before melting stops. The initial mechanism (melting stops) actually necessitates small arctic feedbacks because it precludes the possibility of further ice loss.

Anyways, going back to albedo one thing to keep in mind is that the arctic has so much less snow and ice now than it does in interglacials. The arctic is nearly snow-free in summer already outside of Greenland and sea ice. Milankovitch cycles can trigger interglacials because say if summer snow extended to 45N and an initial warming caused it to retreat to 46N.. that is a surface area 4.3X greater than if it retreated from 80N to 81N.

Remember, we're already in an interglacial. Surface albedo change can still be significant, but not nearly as large as interglacials. As I said before removing all sea ice throughout the ENTIRE YEAR provides a forcing of only .7W/m2.

[TerryM]

Skier, Weather Rusty

Unlike heating due to GHG, all the sensible heat released is going to occur in or over the Arctic Ocean. Other feedbacks will occur over a wider area, but the sensible heat is limited to the area where the ice was present at maximum, and that's all this exercise is concerning itself with.

The number Skier and I agreed to use was >1 x10^20J. It's a substantial number.

The total electrical consumption of the US for 10 years is 1.4 x 10^20J - based on 2009 usage.

A Hiroshima explosion every 10 seconds for one yr yields 2,1 x 10^20J

The total world's energy consumption for 2010 is given as 5.0 x 10^20J - by Wikipedia

The following was intended as a reply to Skier's post yesterday

Whether we work with Watts of Joules (power or energy) shouldn't have an effect since

1 Watt second = 1 Joule & 1 Joule second = 1 Watt

We're in agreement that >3.2x10^12J/second is the amount of energy that will be released when latent heat isn't a factor. This is being released into the Arctic Ocean (where the ice had been), and is in addition to whatever additional energy GHG's and other feedbacks are occurring.

The area of the Arctic ocean is ~1.4 x10^12m2

The energy per m2 = 3,2 x 10^12/1.4 x 10^12 = 2.86 Watts per second/m2

1 Watt second = .2388 calories

2.86 Watt second = .683 cal

therefor

each hour, each sq meter of the Arctic Ocean's surface gains .683 x 3600=2,459 cal

1 cal raises 1 gram of water 1 degreeC

so each hour 2.459Kg water increases 1C in every m2 of the Arctic Ocean

or

each hour of the year the top 1 meter of the Arctic Ocean would be raised by 0.002459C

each day by 0.002459C x 24 = .059C

each month by.059 x 30 = 1.77C

and by the end of the year the top 1 meter of water will have been raised by 1.77 x 12 = 21.246C

or 21.55 if we calculate to 365.25 days

In actuality much of this heat will have transferred to the atmosphere, some will have escaped through the clouds caused by so much open water, made it through the maze of GHG awaiting higher up and escaped into space.

This is a huge amount of heat that's in addition to the warming the Arctic is presently experiencing. Any additional radiation experienced due to lowered albedo or retained by increasing GHGs should also be factored in.- but that's a different equation.

The warmth won't all stay in the top meter of the ocean of course, but this amount of sensible heat energy will be released each year that the ice melts out totally. Since we were working with 1 x 10^20J as our starting figure, and recent years have seen over 3 times as much ice melting away, it's reasonable to assume that by the time this occurs a multiple of at least 3 has to be applied.

I had hesitated to post this because the numbers seem impossibly high, but I've gone back over the math and don't see where I'm messing it up. If I've made a mistake somewhere let me know.

The amount of heat that will be radiated into space, subducted into the deep oceans or that will eventually be distributed through the globe doesn't affect these calculations that are only concerned with the amount of energy that at present is being used to melt Arctic sea ice.

Please find a flaw in the math - the numbers are too high to be real, but everything adds up.

Terry

[skierinvermont]

You're kind of mixing up units and you are also dramatically underestimating how much a surface temperature rise will increase radiation to space. If we follow your assumption that the ocean is only 1 meter deep, it would only take a few days for the surface of the ocean to warm enough to increase radiation to space by an equal quantity to that which used to go into melting ice. Not an entire year. Bolded are my corrections to you units. Following you post is my calculation of how it would only take a few days for the surface to warm enough to re-emit the extra energy to space.

Skier, Weather Rusty

Unlike heating due to GHG, all the sensible heat released is going to occur in or over the Arctic Ocean. Other feedbacks will occur over a wider area, but the sensible heat is limited to the area where the ice was present at maximum, and that's all this exercise is concerning itself with.

The number Skier and I agreed to use was >1 x10^20J. It's a substantial number.

The total electrical consumption of the US for 10 years is 1.4 x 10^20J - based on 2009 usage.

A Hiroshima explosion every 10 seconds for one yr yields 2,1 x 10^20J

The total world's energy consumption for 2010 is given as 5.0 x 10^20J - by Wikipedia

The following was intended as a reply to Skier's post yesterday

Whether we work with Watts of Joules (power or energy) shouldn't have an effect since

1 Watt second = 1 Joule & 1 Joule second = 1 Watt no, 1 joule PER second = 1 watt

We're in agreement that >3.2x10^12J/second is the amount of energy that will be released when latent heat isn't a factor. This is being released into the Arctic Ocean (where the ice had been), and is in addition to whatever additional energy GHG's and other feedbacks are occurring.

The area of the Arctic ocean is ~1.4 x10^12m2

The energy per m2 = 3,2 x 10^12/1.4 x 10^12 = 2.86 Watts per second/m2 No, it's 2.86 Joules per second per m2 or 2.86W/m2 or 2.86 watt seconds per second per m2 ( a very convoluted way of expressing it)

1 Watt second = .2388 calories

2.86 Watt second = .683 cal

therefor

each hour, each sq meter of the Arctic Ocean's surface gains .683 cal/second x 3600 seconds=2,459 cal (you've come up with the right answer perhaps by intuition, because you definitely were mixing units along the way)

1 cal raises 1 gram of water 1 degreeC

so each hour 2.459Kg water increases 1C in every m2 of the Arctic Ocean

or

each hour of the year the top 1 meter of the Arctic Ocean would be raised by 0.002459C

each day by 0.002459C x 24 = .059C

each month by.059 x 30 = 1.77C

and by the end of the year the top 1 meter of water will have been raised by 1.77 x 12 = 21.246C

or 21.55 if we calculate to 365.25 days

In actuality much of this heat will have transferred to the atmosphere, some will have escaped through the clouds caused by so much open water, made it through the maze of GHG awaiting higher up and escaped into space.

This is a huge amount of heat that's in addition to the warming the Arctic is presently experiencing. Any additional radiation experienced due to lowered albedo or retained by increasing GHGs should also be factored in.- but that's a different equation.

The warmth won't all stay in the top meter of the ocean of course, but this amount of sensible heat energy will be released each year that the ice melts out totally. Since we were working with 1 x 10^20J as our starting figure, and recent years have seen over 3 times as much ice melting away, it's reasonable to assume that by the time this occurs a multiple of at least 3 has to be applied.

I had hesitated to post this because the numbers seem impossibly high, but I've gone back over the math and don't see where I'm messing it up. If I've made a mistake somewhere let me know.

The amount of heat that will be radiated into space, subducted into the deep oceans or that will eventually be distributed through the globe doesn't affect these calculations that are only concerned with the amount of energy that at present is being used to melt Arctic sea ice.

Please find a flaw in the math - the numbers are too high to be real, but everything adds up.

Terry

According to planck/stefan boltzman once the surface of the arctic increased by .9C it would be able to completely radiate all of the extra heat added to space.

We can both agree that the arctic would be absorbing energy at a rate of 2.86 Joules per second that previously went into melting of ice.

If the surface of the arctic warms by .9C, it will increase energy emissions to space by an equal quantity to that which you have calculated.

Thus we would never even begin to approach the 21C+ that you have calculated, because long before then emissions to space would have increased sufficiently to offset the new source of energy. It would only take 15 days for surface temperatures to rise .9C assuming we only are heating the top 1 meter of ocean.

If we assume we have to heat much deeper than 1 meter, it will take longer for equilibrium to be reached, but it will still only require .9C of warming in the arctic. Also as you approach the equilibrium temperature, the net energy imbalance is reduced and it takes longer to reach equilibrium.

In reality, the warming would not be confined to the arctic. You'd probably see like .2 or .3C concentrated in the arctic, and .0015C everywhere else averaged. Globally, as I said before it would be .0018C on average including the more concentrated warming in the arctic.

We can provide a double check on my math. .9C over an area of 1.4X10^12 m2 (arctic ocean) is .0024C over the surface area of the earth (5.1X10^14 m2).

.0024C is pretty close to the .0018C I have calculated all along.. the difference is probably due to sloppy rounding

You're not really understanding how much radiation to space increases when you increase surface temperature. Like you're underballing it by several orders of magnitude. You'd never get remotely close to a 21C surface temperature rise in the arctic because radiation to space would increase so much first. It would be like ejecting the energy equivalent to a hiroshima into space every second. Very slight changes in surface temperature produce massive changes in the energy budget of a region or the earth as a whole.

[WeatherRusty]

Excertped from Wikipedia

EDIT: I was forced to cut out the derivation equations due to image restrictions imposed by the forum.

Radiative power

Thermal radiation power of a black body per unit of solid angle and per unit frequency is given by Planck's law as:

This formula mathematically follows from calculation of spectral distribution of energy in quantized electromagnetic field which is in complete thermal equilibrium with the radiating object. The equation is derived as an infinite sum over all possible frequencies. The energy, , of each photon is multiplied by the number of states available at that frequency, and the probability that each of those states will be occupied.

Integrating the above equation over the power output given by the Stefan–Boltzmann law is obtained, as:

where the constant of proportionality is the Stefan–Boltzmann constant and is the radiating surface area.

__________________

The Planck Law determines the spectral distribution of frequency and wavelengths.

Stefan-Boltzmann determines the power emitted given that distribution.

The key point backing skier's argument is the factor T to the 4th power. If we double the surface temperature, the power of emissivity increases by 16 times!

[TerryM]

I was off by about one order of magnitude. I knew something was wrong with my calculations because the answer I was getting wasn't reasonable.

I'll post the much simplified method - hopefully later today.

Thanks to all for the feedback.

Terry

[skierinvermont]

I was off by about one order of magnitude. I knew something was wrong with my calculations because the answer I was getting wasn't reasonable.

I'll post the much simplified method - hopefully later today.

Thanks to all for the feedback.

Terry

You're original calculation was correct given the assumptions you were operating with 1) there is an insignificant increase in radiation to space (false assumption - a small increase in temperature will increase radiation to space dramatically) and 2) we are only heating the top 1m of ocean.

[noiv]

New study finds that regarding cloud feedback and humidity climate sensitivity might be at the higher end of the range. At least that's what the models simulating seasonal drying in the subtropics and the associated decrease in clouds according to the observations propose.

It's a new approach needing further backup, but if it's right the 2°C target is dead.

Paper: http://www.sciencema...108/755.summary

Press: https://www2.ucar.ed...-analysis-finds

News: http://news.national...ative-humidity/

[TerryM]

Just a bump for noiv's post.

Terry

[HailMan06]

Bump

Thanks Will for directing people to this page.

[PhillipS]

Bump

Thanks Will for directing people to this page.

 

HailMan - please provide links to the studies you feel support a lower climate sensitivity.

 

I just did a quick Google Scholar search for recent (2013) papers on global climate sensitivity and didn't find anything radically different from previous estimates.  The one that seemed to me to be most relevant was Lewis 2013 [link] titled 

An objective Bayesian, improved approach for applying optimal fingerprint techniques to estimate climate sensitivity

and its abstract:

 

A detailed reanalysis is presented of a ‘Bayesian’ climate parameter study (Forest et al., 2006) that estimates climate sensitivity (ECS) jointly with effective ocean diffusivity and aerosol forcing, using optimal fingerprints to compare multi-decadal observations with simulations by the MIT 2D climate model at varying settings of the three climate parameters. Use of improved methodology primarily accounts for the 90% confidence bounds for ECS reducing from 2.1–8.9 K to 2.0–3.6 K. The revised methodology uses Bayes’ theorem to derive a probability density function (PDF) for the whitened (made independent using an optimal fingerprint transformation) observations, for which a uniform prior is known to be noninformative. A dimensionally-reducing change of variables onto the parameter surface is then made, deriving an objective joint PDF for the climate parameters. The PDF conversion factor from the whitened variables space to the parameter surface represents a noninformative joint parameter prior, which is far from uniform. The noninformative prior prevents more probability than data uncertainty distributions warrant being assigned to regions where data responds little to parameter changes, producing better-constrained PDFs. Incorporating six years of unused model-simulation data and revising the experimental design to improve diagnostic power reduces the best-fit climate sensitivity. Employing the improved methodology, preferred 90% bounds of 1.2–2.2 K for ECS are then derived (mode and median 1.6 K). The mode is identical to those from Aldrin et al. (2012) and (using the same, HadCRUT4, observational dataset) Ring et al. (2012). Incorporating forcing and observational surface temperature uncertainties, unlike in the original study, widens the 90% range to 1.0–3.0 K.

 

Several things I noticed from the abstract - 

• It's a statistical approach rather than a physics and observation based approach to refining Estimated Climate Sensitivity (ECS) values.  Perhaps it will hold up to scrutiny but I confess I'm skeptical.  Remember the old adage "There're lies, damn lies, and statistics."
• The study used climate models extensively instead of observational records.
• The final result was an ECS 90% range of 1.0 - 3.0 C.  Since a widely reported limit for 'tolerable' global warming is 2.0 C ( and we've already observed 0.8 C warming) it sounds like we will probably see severe climate degradation in our lifetimes.

But I'd love to be wrong on this so maybe the papers you mentioned will be reassuring.

[SVT450R]

Phillips i think you meant to refer to blue sky he started the new sensitivity thread without links.

[PhillipS]

Phillips i think you meant to refer to blue sky he started the new sensitivity thread without links.

  Oops, you're right - I should of directed my post to Blue Sky.  

[HailMan06]

Yeah I was agreeing with Will to close the other thread and direct others to this one since that one was started for trolling CC.

[SVT450R]

Global Warming Caused by CFCs, Not Carbon Dioxide, Researcher Claims in Controversial Study

http://www.sciencedaily.com/releases/2013/05/130530132443.htm

 

May 30, 2013 — Chlorofluorocarbons (CFCs) are to blame for global warming since the 1970s and not carbon dioxide, according to a researcher from the University of Waterloo in a controversial new study published in the International Journal of Modern Physics B this week.

 

CFCs are already known to deplete ozone, but in-depth statistical analysis now suggests that CFCs are also the key driver in global climate change, rather than carbon dioxide (CO₂) emissions, the researcher argues.

"Conventional thinking says that the emission of human-made non-CFC gases such as carbon dioxide has mainly contributed to global warming. But we have observed data going back to the Industrial Revolution that convincingly shows that conventional understanding is wrong," said Qing-Bin Lu, a professor of physics and astronomy, biology and chemistry in Waterloo's Faculty of Science. "In fact, the data shows that CFCs conspiring with cosmic rays caused both the polar ozone hole and global warming."

"Most conventional theories expect that global temperatures will continue to increase as CO₂ levels continue to rise, as they have done since 1850. What's striking is that since 2002, global temperatures have actually declined -- matching a decline in CFCs in the atmosphere," Professor Lu said. "My calculations of CFC greenhouse effect show that there was global warming by about 0.6 °C from 1950 to 2002, but the earth has actually cooled since 2002. The cooling trend is set to continue for the next 50-70 years as the amount of CFCs in the atmosphere continues to decline."

The findings are based on in-depth statistical analyses of observed data from 1850 up to the present time, Professor Lu's cosmic-ray-driven electron-reaction (CRE) theory of ozone depletion and his previous research into Antarctic ozone depletion and global surface temperatures.

"It was generally accepted for more than two decades that the Earth's ozone layer was depleted by the sun's ultraviolet light-induced destruction of CFCs in the atmosphere," he said. "But in contrast, CRE theory says cosmic rays -- energy particles originating in space -- play the dominant role in breaking down ozone-depleting molecules and then ozone."

Lu's theory has been confirmed by ongoing observations of cosmic ray, CFC, ozone and stratospheric temperature data over several 11-year solar cycles. "CRE is the only theory that provides us with an excellent reproduction of 11-year cyclic variations of both polar ozone loss and stratospheric cooling," said Professor Lu. "After removing the natural cosmic-ray effect, my new paper shows a pronounced recovery by ~20% of the Antarctic ozone hole, consistent with the decline of CFCs in the polar stratosphere."

By demonstrating the link between CFCs, ozone depletion and temperature changes in the Antarctic, Professor Lu was able to draw almost perfect correlation between rising global surface temperatures and CFCs in the atmosphere.

"The climate in the Antarctic stratosphere has been completely controlled by CFCs and cosmic rays, with no CO₂ impact. The change in global surface temperature after the removal of the solar effect has shown zero correlation with CO₂ but a nearly perfect linear correlation with CFCs -- a correlation coefficient as high as 0.97."

Data recorded from 1850 to 1970, before any significant CFC emissions, show that CO₂ levels increased significantly as a result of the Industrial Revolution, but the global temperature, excluding the solar effect, kept nearly constant. The conventional warming model of CO₂, suggests the temperatures should have risen by 0.6°C over the same period, similar to the period of 1970-2002.

The analyses support Lu's CRE theory and point to the success of the Montreal Protocol on Substances that Deplete the Ozone Layer.

"We've known for some time that CFCs have a really damaging effect on our atmosphere and we've taken measures to reduce their emissions," Professor Lu said. "We now know that international efforts such as the Montreal Protocol have also had a profound effect on global warming but they must be placed on firmer scientific ground."

"This study underlines the importance of understanding the basic science underlying ozone depletion and global climate change," said Terry McMahon, dean of the faculty of science. "This research is of particular importance not only to the research community, but to policy makers and the public alike as we look to the future of our climate."

Professor Lu's paper, "Cosmic-Ray-Driven Reaction and Greenhouse Effect of Halogenated Molecules: Culprits for Atmospheric Ozone Depletion and Global Climate Change," also predicts that the global sea level will continue to rise for some years as the hole in the ozone recovers increasing ice melting in the polar regions.

"Only when the effect of the global temperature recovery dominates over that of the polar ozone hole recovery, will both temperature and polar ice melting drop concurrently," says Lu.

The peer-reviewed paper published this week not only provides new fundamental understanding of the ozone hole and global climate change but has superior predictive capabilities, compared with the conventional sunlight-driven ozone-depleting and CO₂-warming models, Lu argues.

 

 

[PhillipS]

Global Warming Caused by CFCs, Not Carbon Dioxide, Researcher Claims in Controversial Study

http://www.sciencedaily.com/releases/2013/05/130530132443.htm

 

May 30, 2013 — Chlorofluorocarbons (CFCs) are to blame for global warming since the 1970s and not carbon dioxide, according to a researcher from the University of Waterloo in a controversial new study published in the International Journal of Modern Physics B this week.

 

CFCs are already known to deplete ozone, but in-depth statistical analysis now suggests that CFCs are also the key driver in global climate change, rather than carbon dioxide (CO₂) emissions, the researcher argues.

"Conventional thinking says that the emission of human-made non-CFC gases such as carbon dioxide has mainly contributed to global warming. But we have observed data going back to the Industrial Revolution that convincingly shows that conventional understanding is wrong," said Qing-Bin Lu, a professor of physics and astronomy, biology and chemistry in Waterloo's Faculty of Science. "In fact, the data shows that CFCs conspiring with cosmic rays caused both the polar ozone hole and global warming."

"Most conventional theories expect that global temperatures will continue to increase as CO₂ levels continue to rise, as they have done since 1850. What's striking is that since 2002, global temperatures have actually declined -- matching a decline in CFCs in the atmosphere," Professor Lu said. "My calculations of CFC greenhouse effect show that there was global warming by about 0.6 °C from 1950 to 2002, but the earth has actually cooled since 2002. The cooling trend is set to continue for the next 50-70 years as the amount of CFCs in the atmosphere continues to decline."

The findings are based on in-depth statistical analyses of observed data from 1850 up to the present time, Professor Lu's cosmic-ray-driven electron-reaction (CRE) theory of ozone depletion and his previous research into Antarctic ozone depletion and global surface temperatures.

"It was generally accepted for more than two decades that the Earth's ozone layer was depleted by the sun's ultraviolet light-induced destruction of CFCs in the atmosphere," he said. "But in contrast, CRE theory says cosmic rays -- energy particles originating in space -- play the dominant role in breaking down ozone-depleting molecules and then ozone."

Lu's theory has been confirmed by ongoing observations of cosmic ray, CFC, ozone and stratospheric temperature data over several 11-year solar cycles. "CRE is the only theory that provides us with an excellent reproduction of 11-year cyclic variations of both polar ozone loss and stratospheric cooling," said Professor Lu. "After removing the natural cosmic-ray effect, my new paper shows a pronounced recovery by ~20% of the Antarctic ozone hole, consistent with the decline of CFCs in the polar stratosphere."

By demonstrating the link between CFCs, ozone depletion and temperature changes in the Antarctic, Professor Lu was able to draw almost perfect correlation between rising global surface temperatures and CFCs in the atmosphere.

"The climate in the Antarctic stratosphere has been completely controlled by CFCs and cosmic rays, with no CO₂ impact. The change in global surface temperature after the removal of the solar effect has shown zero correlation with CO₂ but a nearly perfect linear correlation with CFCs -- a correlation coefficient as high as 0.97."

Data recorded from 1850 to 1970, before any significant CFC emissions, show that CO₂ levels increased significantly as a result of the Industrial Revolution, but the global temperature, excluding the solar effect, kept nearly constant. The conventional warming model of CO₂, suggests the temperatures should have risen by 0.6°C over the same period, similar to the period of 1970-2002.

The analyses support Lu's CRE theory and point to the success of the Montreal Protocol on Substances that Deplete the Ozone Layer.

"We've known for some time that CFCs have a really damaging effect on our atmosphere and we've taken measures to reduce their emissions," Professor Lu said. "We now know that international efforts such as the Montreal Protocol have also had a profound effect on global warming but they must be placed on firmer scientific ground."

"This study underlines the importance of understanding the basic science underlying ozone depletion and global climate change," said Terry McMahon, dean of the faculty of science. "This research is of particular importance not only to the research community, but to policy makers and the public alike as we look to the future of our climate."

Professor Lu's paper, "Cosmic-Ray-Driven Reaction and Greenhouse Effect of Halogenated Molecules: Culprits for Atmospheric Ozone Depletion and Global Climate Change," also predicts that the global sea level will continue to rise for some years as the hole in the ozone recovers increasing ice melting in the polar regions.

"Only when the effect of the global temperature recovery dominates over that of the polar ozone hole recovery, will both temperature and polar ice melting drop concurrently," says Lu.

The peer-reviewed paper published this week not only provides new fundamental understanding of the ozone hole and global climate change but has superior predictive capabilities, compared with the conventional sunlight-driven ozone-depleting and CO₂-warming models, Lu argues.

130530132443-large.jpg

 

I was waiting to see whether one of the pseudo-skeptics would post that paper and, bless your heart, you didn't disappoint.  Having read the abstract and done some quick reality-checking reading, it is my opinion that this paper will not hold up to scrutiny and will quickly be forgotten by all but the hard-core denialists (who, of course, will keep trotting it out every few months).

 

Just several reasons the paper isn't credible:

 

1. CFCs are not GHGs, but CO2 is.  For the paper to have any legitimacy it has to describe a physics based mechanism for how CFCs could cause the observed global warming, as well as robust reasons for why CO2 and other GHGs stopped being GHGs.  All the paper puts forth is a statistical analysis that seems to show a correlation between CFCs and global temps.  Haven't you ever heard the fundamental principle of science that correlation does not imply causation?

 

2.  CFCs are a very trace gas.  Denialists love to claim that CO2 can't be causing the observed warming because it is too small a fraction of the atmosphere.  Well, compared to CFCs, CO2 is a major component of the air.  Here are the current ESRL plots for CFC-11 and CFC-12:

 

 

 

Notice the values on the y-axis - the combined values only add up to around 800 ppt.  That's parts per TRILLION.  For the purposes of this post I'll round that sum up to 1,000 ppt, also expressed as 1 ppb.  The current value for CO2 is around 400 ppm, or 400,000 ppb.  Does the light begin to come on?  The concentration of CO2, just one of several GHGs, is about four hundred thousand times that of all CFCs combined - yet the paper you posted is claiming that some unspecified CFC process is both blocking the GHE of GHGs and is warming the Earth by the same amount.

 

3.  If the paper is correct then the global climate must be extremely sensitive to tiny perturbations because all of the CFCs ever produced never raised the atmospheric concentration above 1 ppb.  If 0.8 C of warming was caused by a few parts per trillion of CFCs, imagine the holocaust that would result from 1 ppm (1,000,000 ppt).  It boggles the mind.

 

Oh well, this paper goes to show that being peer-reviewed is no guarantee of quality.  Honest skepticism is still important.

 

Oops, I just realized I made an order of magnitude error.  1 ppm = 1,000,000 ppt, not 100,000 ppt as I originally wrote.  Gosh is my face red.

[SVT450R]

Phillips i was only posting the article never said i believed it.

[PhillipS]

Phillips i was only posting the article never said i believed it.

 

SVT - if you were just posting it to give us all a good chuckle then I apologize for the tone of my post.  Silly me, I thought you were posting it because you found it believable..

[ben4vols]

SVT - if you were just posting it to give us all a good chuckle then I apologize for the tone of my post.  Silly me, I thought you were posting it because you found it believable..

 

You being someone who puts validity in the IPCC, I wouldn't laugh too hard at what others find "believable". 

 

[ORH_wxman]

You being someone who puts validity in the IPCC, I wouldn't laugh too hard at what others find "believable". 

 

 

 

 

There's a massive difference between finding the IPCC believable or not in their sensitivity estimates and believing that paper about CFCs.

 

IPCC already has a lot of peer review papers (as well as a short duration of observations) arguing against their AR4 report on the sensitivity whereas this other paper is basically out of left field.

[ben4vols]

There's a massive difference between finding the IPCC believable or not in their sensitivity estimates and believing that paper about CFCs.

 

I don't think so.  Has the IPCC shown itself to be credible and worthy of believability?  Usually one can find the IPCC wandering about in left field itself and its' own dire predictions based on its' faulty modeling which is based on a somewhat faulty hypothesis are starting to come home to roost.  Also, I agree the CFC paper is out in left field.  That being said I do think the "cloud people" are on to something that will one day prove to be beneficial. 

[Snow_Miser]

This thread needs a bump.

 

http://online.wsj.com/article/SB10001424127887324549004579067532485712464.html

 

"Specifically, the draft report says that "equilibrium climate sensitivity" (ECS)—eventual warming induced by a doubling of carbon dioxide in the atmosphere, which takes hundreds of years to occur—is "extremely likely" to be above 1 degree Celsius (1.8 degrees Fahrenheit), "likely" to be above 1.5 degrees Celsius (2.4 degrees Fahrenheit) and "very likely" to be below 6 degrees Celsius (10.8 Fahrenheit). In 2007, the IPPC said it was "likely" to be above 2 degrees Celsius and "very likely" to be above 1.5 degrees, with no upper limit. Since "extremely" and "very" have specific and different statistical meanings here, comparison is difficult.

 

Still, the downward movement since 2007 is clear, especially at the bottom of the "likely" range. The most probable value (3 degrees Celsius last time) is for some reason not stated this time.

 

A more immediately relevant measure of likely warming has also come down: "transient climate response" (TCR)—the actual temperature change expected from a doubling of carbon dioxide about 70 years from now, without the delayed effects that come in the next century. The new report will say that this change is "likely" to be 1 to 2.5 degrees Celsius and "extremely unlikely" to be greater than 3 degrees. This again is lower than when last estimated in 2007 ("very likely" warming of 1 to 3 degrees Celsius, based on models, or 1 to 3.5 degrees, based on observational studies).

 

Most experts believe that warming of less than 2 degrees Celsius from preindustrial levels will result in no net economic and ecological damage. Therefore, the new report is effectively saying (based on the middle of the range of the IPCC's emissions scenarios) that there is a better than 50-50 chance that by 2083, the benefits of climate change will still outweigh the harm."

 

Thoughts?

[calculus1]

My apologies for not seeing this article posted and re-posting it in another thread.