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Author Topic: IPCC possible scenario: 9 C over next century or so  (Read 142026 times)

Sleepy

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #250 on: April 29, 2015, 02:33:57 PM »
No, no Neven. It's not impossible at all.
That's where the manufacturers oligopoly comes in and controls the market. In the beginning (late 19th century) HC (Hydrocarbons) was used, and also CO2. There IS a use for CO2!  ;) The downside with CO2 is the high pressure. But there are machines to buy today again.

The downside with HC is fire. If you use R-134a in an AC you can use Propane (R-290) instead. In the case of R-410a the pressure needed is higher so you can't use Propane as it is. I tested one R-410a last year with only Propylene (R-1270) which is slightly better than Propane and what I needed was Ethane (R-170) to get it right. Unfortunately it was hard to buy Ethane here and when I finally found a reseller it was terribly expensive. But it will work with the right blend. Further testing was cancelled but I used that machine more than eight months with only Propylene. Somewhere just above 80/20% R-1270/R-170 would have been right. The simulated curves in coolpack (software) with 80/20% were almost identical.

And if the machine needs 1kg of dangersoup, it only (roughly) needs 0,5kg of HC.

Sleepy

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #251 on: April 29, 2015, 05:21:46 PM »
My previous reply was of course to Nevens #249, I was in a hurry and just posted it allthough there was a comment in between.
My main point was that the manufacturers can build machines without those patented refrigerants.


One of the problems with all of these smaller units below 3kg's of refrigerant is that leak checks and end of life recovery is unheard of. Its more or less up to the owner. And most/all of them will leak over time.

Now with the new f-gas regulations the new CO2 thresholds will require some systems below the old 3kg threshold to be regularly leak tested as they are based on CO2e. But that won't help much as you can see below. A lot of domestic machines are at, or around, 1kg.
http://www.fridgehub.com/News/900-european-f-gas-regulation-guidance-understanding-co2-size-thresholds

Csnavywx

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #252 on: May 01, 2015, 12:34:44 AM »
10 ppt of HFC at 10k GWP is 0.1 ppm CO2e. Not a big deal. Now, if we get another 10-fold jump in the emission rate (0.1ppm CO2e/yr), then it starts to become an issue.

Sleepy

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #253 on: May 01, 2015, 06:40:53 AM »
Well, it's an "easy" fix, could have been done a long time ago because we don't need it.
In fact, it would have been better if refrigerants like R-410a never were invented, R-125 is totally useless as a refrigerant and heat pumps constructed before those were easier to convert to HC because they needed less pressure. It's not flammable, but in contact with fire it's highly carcinogenic. Don't smoke...

There are a lot of those heat pumps built 10-20 years ago still in use. We will see a further increase, look at that graph for HFC-32 (from the study that ASLR posted) and remember that it is part of blended refrigerants like R-410a (50%). Attached readings for HFC-125.

And people in general still see them as "clean" non ozone depleting substances beacuse they are marketed like that.


Considering the wider picture.
Two reports from EPA that displays large uncertanties.
http://www.epa.gov/ozone/snap/emissions/downloads/FoamEmissionProfiles_Part3.pdf
http://www.epa.gov/climatechange/Downloads/ghgemissions/US-GHG-Inventory-2015-Annex-6-Additional-Information.pdf

I'll add one graph from the first one. Apart from those refrigerants, consider the truckload of substances left out, and other uncertanties not included in that picture. We could at least drop those we don't need at all.

icefest

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #254 on: May 18, 2015, 01:01:51 PM »
Neven, it has a gwp of roughly 1300. Whether it's better depends on your power source; here in Australia it'd probably be better after about a year.
http://www.epa.gov/ozone/geninfo/gwps.html
Open other end.

Neven

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #255 on: May 18, 2015, 10:06:55 PM »
Neven, it has a gwp of roughly 1300. Whether it's better depends on your power source; here in Australia it'd probably be better after about a year.
http://www.epa.gov/ozone/geninfo/gwps.html

I estimate 75% of the energy needed to run the heat pump comes from the solar panels on the roof. The rest is so-called 'green energy'. The heat pump needs around 2 kWh per day, but that was during winter, so I think it will go down to 1.5 kWh per day. The heat pump has a COP of 4.

So basically an electric boiler would use 6 kWh per day, that's 2190 kWh per year. If this energy came from coal, 900 grams of CO2 would be produced per kWh. So total would be 1971 kg of CO2 per year.

From the link you posted:

Quote
The global warming potential (GWP) represents how much a given mass of a chemical contributes to global warming over a given time period compared to the same mass of carbon dioxide. Carbon dioxide's GWP is defined as 1.0.

Like I said, my heat pump contains 0.7 kg of R-134a refrigerant, times 1300 GWP = 910 kg of CO2.

Okay, I'm less worried now. Thanks for the info, icefest!  :) 8)
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icefest

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #256 on: May 20, 2015, 06:55:42 AM »
:)
Open other end.

Sleepy

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #257 on: May 20, 2015, 07:17:54 AM »
Maybe I'm sleepier than usual?  ;)
The same link was provided in my Reply #248 and with a further explanation in the second link in Reply #254. There are alternatives to the patented blends from the refrigerant oligopoly.

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #258 on: August 21, 2017, 08:59:01 AM »
From the link you posted:

Quote
The global warming potential (GWP) represents how much a given mass of a chemical contributes to global warming over a given time period compared to the same mass of carbon dioxide. Carbon dioxide's GWP is defined as 1.0.

Like I said, my heat pump contains 0.7 kg of R-134a refrigerant, times 1300 GWP = 910 kg of CO2.

Okay, I'm less worried now. Thanks for the info, icefest!  :) 8)

This is still off-topic, but just wanted to report that our heat pump was becoming increasingly inefficient. Turns out there isn't enough refrigerant (R134a) in the system, meaning some of it has leaked. There's a plumber pumping out the rest, as I write this, so he can put new refrigerant in.

He put the hose out the window and he was smiling at me while opening the valve. All I could think about was how we added one tonne of CO2e to the atmosphere (6 months of driving with our current CNG-powered car).  :( :'(

Here's to hoping the leak isn't permanent...
The enemy is within
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E. Smith

AbruptSLR

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #259 on: August 21, 2017, 05:07:38 PM »
The first linked article entitled: "Investigating the Enigma of Clouds and Climate Change", indicates that net cloud feedback is more positive than previously assumed as satellite data confirms that with warming, clouds are both moving higher and pole-ward.

http://e360.yale.edu/features/investigating-the-enigma-of-clouds-and-climate-change

Extract: "In an interview with Yale Environment 360, Marvel discusses what is known about the behavior of clouds in a warming world (they are migrating more toward the poles), explains why strict controls need to be imposed on geoengineering experiments with clouds …
..
e360: What are the consequences of this poleward and upward motion of clouds?

Marvel: Both of them give rise to what I think is the most confusing part of climate jargon. We call it a positive feedback, and you think “positive feedback” — that sounds great. I like getting positive feedback. But when climate scientists talk about a positive feedback, we mean some process that changes in response to warming, that accelerates that warming. So both of those changes are what we would call a positive feedback, meaning it enhances the warming.

Marvel: People ask me, “Aren’t you just depressed all the time? How do you keep going in the face of this?” We’re all going to die. You know, there’s not a lot of good news there. But we all manage to find happiness and fun in our lives anyway. And I do have hope, I do think that we are an amazing species; and we do a lot of terrible things, but we also do a lot of very good things. I do have hope in human ingenuity."

The second linked reference provides satellite data (see the attached image) from CloudSat & CALIPSO within the A-Train, that show a dramatic increase (more positive) in observed net cloud feedback as compared to prior assumptions.  This of course means that ECS is higher than previously assumed.

Graeme Stephens et. al. (2017), "CloudSat and CALIPSO within the A-Train: Ten years of actively observing the Earth system", BAMS, https://doi.org/10.1175/BAMS-D-16-0324.1

http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-16-0324.1?utm_content=bufferebbb9&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer
or
http://journals.ametsoc.org/doi/pdf/10.1175/BAMS-D-16-0324.1

Abstract: "The more than 10 years of observations jointly collected by CloudSat and CALIPSO satellites has resulted in new ways of looking at aerosol, clouds, and precipitation and new discoveries about processes that connect them.

One of the most successful demonstrations of an integrated approach to observe Earth from multiple perspectives is the A-Train satellite constellation (e.g. Stephens et al., 2002). The science enabled by this constellation flourished with the introduction of the two active sensors carried by the NASA CloudSat and the NASA/CNES Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellites that were launched together on April 28th, 2006. These two missions have provided a 10-year demonstration of coordinated formation flying that made it possible to develop integrated products and that offered new insights on key atmospheric processes. The progress achieved over this decade of observations, summarized in this paper, clearly demonstrate the fundamental importance of the vertical structure of clouds and aerosol for understanding the influences of the larger scale atmospheric circulation on aerosol, the hydrological cycle, the cloud-scale physics and on the formation of the major storm systems of Earth. The research also underscored inherent ambiguities in radiance data in describing cloud properties and how these active systems have greatly enhanced passive observation. It is now clear that monitoring the vertical structure of clouds and aerosol is essential and a climate data record is now being constructed. These pioneering efforts are to be continued with EarthCARE mission planned for launch in 2019."

Caption: "Figure 5 Upper three panels are from Hartmann et al (1992) who estimate the contribution to the cloud radiative effects (CRE) of five classes of clouds as defined according to the ISCCP radiance classification (upper left). The bottom panels are the equivalent analysis but with classification determined by the radar-lidar data of CloudSat and CALIPSO where true cloud heights establish the types and cloud thickness (x axis) are from water and ice path information which is proportional to cloud optical depth. The differences in CRE between this latter analysis and that of Hartmann et al underscores the effects of misclassification of clouds on the interpretation of their radiative effects. Ci=cirrus, D.C.=Deep Convection, M.L.=multi-layer, AS=Altostratus, AC-Alto-cumulus, NS=Nimbostratus, St=stratus, SC=stratocumulus and Cu=cumulus."

Edit: I added bold font to the Kate Marvel interview for emphasis
« Last Edit: August 21, 2017, 05:55:44 PM by AbruptSLR »
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AbruptSLR

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #260 on: August 21, 2017, 06:51:00 PM »
As a follow-on to my last post, the first linked reference runs two modeled radiative forcing scenarios for the Eocene, one driven by high atmospheric CO₂ concentrations and one driven by reduced cloud albedo (and moderate CO₂ concentrations).  "The two simulations have an almost identical global-mean surface temperature and equator-to-pole temperature difference …" but different regional signatures that could be checked using both local paleodata and/or other models run with same forcing scenarios.  It goes without saying that the reduced cloud albedo scenario indicates higher climate sensitivity, and also closely matches the paleodata findings of moderate atmospheric CO₂ concentrations during the Eocene shown in the first attached image

Carlson, H. and Caballero, R.: Atmospheric circulation and hydroclimate impacts of alternative warming scenarios for the Eocene, Clim. Past, 13, 1037-1048, https://doi.org/10.5194/cp-13-1037-2017, 2017.

https://www.clim-past.net/13/1037/2017/

Abstract. Recent work in modelling the warm climates of the early Eocene shows that it is possible to obtain a reasonable global match between model surface temperature and proxy reconstructions, but only by using extremely high atmospheric CO2 concentrations or more modest CO2 levels complemented by a reduction in global cloud albedo. Understanding the mix of radiative forcing that gave rise to Eocene warmth has important implications for constraining Earth's climate sensitivity, but progress in this direction is hampered by the lack of direct proxy constraints on cloud properties. Here, we explore the potential for distinguishing among different radiative forcing scenarios via their impact on regional climate changes. We do this by comparing climate model simulations of two end-member scenarios: one in which the climate is warmed entirely by CO2 (which we refer to as the greenhouse gas (GHG) scenario) and another in which it is warmed entirely by reduced cloud albedo (which we refer to as the low CO2–thin clouds or LCTC scenario) . The two simulations have an almost identical global-mean surface temperature and equator-to-pole temperature difference, but the LCTC scenario has  ∼  11 % greater global-mean precipitation than the GHG scenario. The LCTC scenario also has cooler midlatitude continents and warmer oceans than the GHG scenario and a tropical climate which is significantly more El Niño-like. Extremely high warm-season temperatures in the subtropics are mitigated in the LCTC scenario, while cool-season temperatures are lower at all latitudes. These changes appear large enough to motivate further, more detailed study using other climate models and a more realistic set of modelling assumptions.

The second linked Harvard Gazette article is entitled: "Reconciling predictions of climate change", & I provide the attached second associated image of a panel of the first supplemental figure from Proistosescu & Huybers (2017) that at for at least the climate model HadGEM2-ES the posterior pdf for the near future ECS has a median value of 6C with right-tailed values in the range of 8C, which is very similar to Eocene temperatures (see the third image)  While it is very difficult to say at the moment what model projections are correct, I provide the following general comments:
1. The vast majority of climate models have trouble matching the observed relatively high Arctic Amplification values from paleo periods that are a little bit warmer than today (e.g. see fourth attached image).

2.  The world is currently warming at a rate that is several time faster than during the PETM.

3.  The 100-year CO₂-eq value at the end of 2016 was about 521ppm which is already at Eocene levels.


http://news.harvard.edu/gazette/story/2017/07/conflicting-estimates-of-rise-in-global-temperature-resolved/

Extract: "“The historical pattern of warming is that most of the warming has occurred over land, in particular over the northern hemisphere,” said Cristian Proistosescu, Ph.D ’17, the first author of the paper. “This pattern of warming is known as the fast mode — you put CO2 in the atmosphere and very quickly after that, the land in the northern hemisphere is going to warm.”

But there is also a slow mode of warming, which can take centuries to realize. That warming, which is most associated with the Southern Ocean and the Eastern Equatorial Pacific, comes with positive feedback loops that amplify the process. For example, as the oceans warm, cloud cover decreases, and a white reflecting surface is replaced with a dark absorbent surface.

The researchers developed a mathematical model to parse the two modes within different climate models.

“The models simulate a warming pattern like today’s, but indicate that strong feedbacks kick in when the Southern Ocean and Eastern Equatorial Pacific eventually warm, leading to higher overall temperatures than would simply be extrapolated from the warming seen to date,” said Peter Huybers, professor of Earth and planetary sciences in the Department of Earth and Planetary Science, and of environmental science and engineering at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS), the co-author of the paper.

Huybers and Proistosescu found that while the slow mode of warming contributes a great deal to the ultimate amount of global warming, it is barely present in present-day warming patterns. “Historical observations give us a lot of insight into how climate changes and are an important test of our climate models,” said Huybers, “but there is no perfect analogue for the changes that are coming.”"

See also:
Cristian Proistosescu and Peter J. Huybers (05 Jul 2017), "Slow climate mode reconciles historical and model-based estimates of climate sensitivity", Science Advances, Vol. 3, no. 7, e1602821, DOI: 10.1126/sciadv.1602821

http://advances.sciencemag.org/content/3/7/e1602821

Extract: "The latest Intergovernmental Panel on Climate Change Assessment Report widened the equilibrium climate sensitivity (ECS) range from 2° to 4.5°C to an updated range of 1.5° to 4.5°C in order to account for the lack of consensus between estimates based on models and historical observations. The historical ECS estimates range from 1.5° to 3°C and are derived assuming a linear radiative response to warming. A Bayesian methodology applied to 24 models, however, documents curvature in the radiative response to warming from an evolving contribution of interannual to centennial modes of radiative response. Centennial modes display stronger amplifying feedbacks and ultimately contribute 28 to 68% (90% credible interval) of equilibrium warming, yet they comprise only 1 to 7% of current warming. Accounting for these unresolved centennial contributions brings historical records into agreement with model-derived ECS estimates."
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mustangchef

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #261 on: August 25, 2017, 03:09:12 AM »
sometimes

AbruptSLR

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #262 on: August 25, 2017, 03:57:36 AM »
Leo DiCaprio hosts a popular October 2016 documentary on the challenges that we are facing in our fight against climate change:

Title: "Before the Flood"


« Last Edit: August 25, 2017, 04:16:33 AM by AbruptSLR »
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rboyd

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #263 on: August 25, 2017, 04:14:31 AM »
Leo DiCaprio hosts a popular 2016 documentary on the challenge that we are facing to fight climate change:

Title: "Before the Flood"



At 1hr 36minutes in, the Indian woman makes DiCaprio very uncomfortable by pointing out the obvious issue with the US high-consumption lifestyle and historic carbon emissions. "Your consumption is going to put a hole in the planet." DiCaprio himself is wide open to denier abuse given his own massive carbon footprint. The Donald could not resist:

https://www.reddit.com/r/The_Donald/comments/6estyw/this_is_leonardo_dicaprios_yacht_this_is_the_same/

jai mitchell

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #264 on: August 30, 2017, 06:10:35 PM »
From the link you posted:

Quote
The global warming potential (GWP) represents how much a given mass of a chemical contributes to global warming over a given time period compared to the same mass of carbon dioxide. Carbon dioxide's GWP is defined as 1.0.

Like I said, my heat pump contains 0.7 kg of R-134a refrigerant, times 1300 GWP = 910 kg of CO2.

Okay, I'm less worried now. Thanks for the info, icefest!  :) 8)

This is still off-topic, but just wanted to report that our heat pump was becoming increasingly inefficient. Turns out there isn't enough refrigerant (R134a) in the system, meaning some of it has leaked. There's a plumber pumping out the rest, as I write this, so he can put new refrigerant in.

He put the hose out the window and he was smiling at me while opening the valve. All I could think about was how we added one tonne of CO2e to the atmosphere (6 months of driving with our current CNG-powered car).  :( :'(

Here's to hoping the leak isn't permanent...

sorry for off topic but wanted to follow up.

Typically a charge should last (at least) 7 years.  This refrigerant doesn't have to be vented to atmosphere but can be captured and recycled.  Proper maintenance and operations, especially if R-134 is recycled makes your system much better for the environment.
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TerryM

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #265 on: August 30, 2017, 08:01:31 PM »
Jai
Sorry, but what Neven experienced is a leak in a sealed system. This should never occur. I've worked on systems >40 years old that still had their original charge.


Neven
Fire whoever did your "repair". Adding Freon to a system without locating and repairing the leak is not acceptable. Leaks do not heal themselves, they get worse. Don't give him a second chance, he's either a crook, or he's inept.


Terry


Neven

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #266 on: August 30, 2017, 08:57:07 PM »
Naturally, that's what I said too. "If there is a leak, refilling it won't help". He said that there was a chance it was due to the caps, where the gas goes in and out, having loosened a bit. Basically, the leak could occur anywhere, not even just in the joints (he said he had seen leaks in every part of the system imaginable), but there would be some oily substance to show for it. And we didn't see any of that anywhere.

I was just happy they didn't charge anything (at 100 euros per hour and the whole operation taking three hours), even though my 2-year warranty had run out a couple of months ago!

So, again: Here's to hoping the leak isn't permanent...  ::)
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Re: IPCC possible scenario: 9 C over next century or so
« Reply #267 on: September 06, 2017, 06:39:31 AM »
Naturally, that's what I said too. "If there is a leak, refilling it won't help". He said that there was a chance it was due to the caps, where the gas goes in and out, having loosened a bit. Basically, the leak could occur anywhere, not even just in the joints (he said he had seen leaks in every part of the system imaginable), but there would be some oily substance to show for it. And we didn't see any of that anywhere.

I was just happy they didn't charge anything (at 100 euros per hour and the whole operation taking three hours), even though my 2-year warranty had run out a couple of months ago!

So, again: Here's to hoping the leak isn't permanent...  ::)


When the time comes that you have to pay find another contractor.


Oil shows in perhaps one out of 20 or one out of fifty leaks.
Caps and Schrader Valve problems account for less than one percent of leaks. (it takes both simultaneously to produce a leak)
Leaks can and must be located and repaired, anything else borders on criminality.


Start saving now, simply adding Freon doesn't solve any problems.
Terry - the bearer of bad tidings.

Neven

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Re: IPCC possible scenario: 9 C over next century or so
« Reply #268 on: September 06, 2017, 10:26:55 AM »
Thanks, Terry!  :P

I'm still hoping for the best, but it looks like this warm water heat pump was a mistake in my design. I should've opted for smaller, well-insulated boilers (one in each bathroom, and one smaller one in the kitchen). As the one upstairs would hardly be used, I'd only have 100 litres downstairs to heat, which is easier than keeping 300 litres warm. Fewer losses over piping as well. And a smaller kitchen boiler, 20 litres or so.

But probably still more kWh annually overall...
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Re: IPCC possible scenario: 9 C over next century or so
« Reply #269 on: September 06, 2017, 08:50:56 PM »
Neven


Some decades ago Germany was manufacturing tiny tankless water heaters, don't know their overall efficiency, but 100% when no hot water is being used. Unless the warm water is also for heating your home they might prove an option.
Solar pre-heaters enjoyed some popularity in California and Nevada, but I'm unsure of their utility in colder climes.


Terry