Environment & Energy
Related: About this forumDavid Wasdell's new paper on climate sensitivity is a bit worrying.
You can retrieve the paper ("Basis for a Carbon Budget?" here: http://www.jayhanson.org/climate.pdf
It's a critical summary of the Recommendations to Policymakers from AR5.
The Executive Summary (my emphasis):
- The adoption of a transient temperature response to cumulative carbon emissions, instead of the full equilibrium impact, allows a higher carbon output before the critical 2°C target is breached. No reference to the substitution is made in the text of the SPM.
- Treating the relationship between temperature response and cumulative carbon emissions as a linear, straight-line function also inflates the available carbon budget by some 10 years worth of emissions at the current rate.
- Removal of all visual representation of the current value of the cumulative carbon emissions, reduces the clarity of the present situation.
- Failure to link the total cumulative carbon emissions to the equivalent concentration of the airborne concentration of CO2 adds to the obfuscation of the presentation.
- Limiting the extent of climatic response to the fast feedback (transient or Charney) dynamics masks dependency on the function of climate sensitivity. This hides uncertainty in the modelling ensemble at the expense of portraying a grossly underestimated temperature response and a massively inflated carbon budget.
- The temperature response to the proposed ceiling of allowed carbon emissions is 5.4°C, not the 2°C indicated in the SPM.[
- The temperature response to the current set of emission-reduction pledges is c. 10°C, not c. 4°C as indicated in the SPM.
- The temperature response to which we are already committed at the present level of cumulative carbon emission is 3.9°C (+ effect of non-CO2 GHG emissions) not 1.5°C implied in the SPM.
- The budget of c. 300GtC of available carbon emission before breaching the 2°C policy target is seen to be an illusion. In reality the carbon account is already overdrawn by c. 288GtC.
- All the above figures should be treated as conservative underestimates as we move from the stable conditions of the Holocene into the far-from-equilibrium, rapid change and enhanced sensitivity of the Anthropocene.
- Recognition of the sensitivity of global climate dynamics to small changes in average surface temperature implies that the degree of safety assumed in the policy target of limiting increase to no more than 2°C above the pre-industrial value, is a delusion.
- Avoiding dangerous climate change is no longer possible. Limiting its intensity requires restriction of the target temperature increase to no more than 1°C.
- Achieving that goal requires reduction in the atmospheric concentration of greenhouse gasses to around 310 ppm of CO2e (from the current value of some 450 ppm CO2e).
On these grounds the Summary for Policymakers of the IPCC AR5 WG1 should be rejected as not fit for the purpose of policy-making. It is a compromise between what is scientifically necessary and what is deemed to be politically and economically feasible. It is a document of appeasement, in active collusion with the global addiction to fossil
sources of energy.
If Wasdell is right...
truebrit71
(20,805 posts)Umm...that doesn't sound good.... :eek:
LouisvilleDem
(303 posts)I'm not comfortable with the tone of this Executive Summary. He makes statements like "The temperature response to the current set of emission-reduction pledges is c. 10°C, not c. 4°C" as if he is correcting someone on the value of PI. The reality is that the values of things related to climate sensitivity (ECS and TCR) are very much unknown at this point in time. In just the past 5 years there have been peer reviewed papers that put TCR at anywhere between 0.9 and 6.0+. To claim that the values the IPCC chose to use in their latest report is 'wrong' is to assert authority that he simply does not have.
GliderGuider
(21,088 posts)LouisvilleDem
(303 posts)Even if it was, at this point in time there is simply no grounds for anyone to say "my paper is right and everyone else's is wrong". It's hubris plain and simple. More than that, it paints a picture so horrible that it leads people to throw up their hands and say "oh well, there is nothing that can be done". Come to think of it, that's probably what you like about it
kristopher
(29,798 posts)There is one industry group that benefits from cultivating that kind of anxiety. They have a product that people would turn to only out of uninformed desperation.
joshcryer
(62,287 posts)And that is precisely why renewables and alternatives have not come online fast enough to stem the catastrophic effects it will cause.
joshcryer
(62,287 posts)If only you'd click the links in the article you'd know that.
LouisvilleDem
(303 posts)The question is, why do you trust the word of a guy who isn't even a climate scientist (he doesn't even have a relevant degree) over that of a group of the world's most prestigious climate scientists?
joshcryer
(62,287 posts)When I started reading his stuff it became apparent that he only mirrored my own thoughts on the matter. Peter Wadhams' stuff in particular is enough to get anyone who takes the science seriously to sit back and reconsider the minimalist approaches they're taking as to not cause people to think they're exaggerating the issues.
Here's the best part. Us alarmists? Us people going "shit is about to hit the fan"? We'll be proven right or wrong in an excitedly short period of time!
LouisvilleDem
(303 posts)joshcryer
(62,287 posts)I say three though.
LouisvilleDem
(303 posts)What will you say if it doesn't happen? Will you admit you were wrong? I certainly will if it goes the other way...
joshcryer
(62,287 posts)See you in three years.
NickB79
(19,297 posts)It was HEAVILY influenced by political and business concerns, and has been roundly criticized for all of the compromises it made in it's language because of objections from industrialized nations.
LouisvilleDem
(303 posts)That's why I'm inclined to trust it.
The alarmists point out that it's projections of sea ice loss were too low, the skeptics point out that it's projections of air temperature rises were too high. I figure when you are getting criticism from both sides it's proof that you probably care more about the truth than what people are saying about you.
NickB79
(19,297 posts)And
http://www.realclimate.org/index.php/archives/2013/11/global-warming-since-1997-underestimated-by-half/
And
http://www.independent.co.uk/news/uk/home-news/has-global-warming-stopped-no--its-just-on-pause-insist-scientists-and-its-down-to-the-oceans-8726893.html
We have zero plausible reasons why sea ice loss estimates were too low.
As time goes on, AR5 appears further and further from touch with reality, and the reality keeps swerving closer and closer to the alarmist position.
Criticism from both sides is no indication you got something right. More often than not, it's simply an indication of bad work done all around. The IPCC had to compromise so much that they lost support among climate scientists, but the fossil fuel industries and industrialized nations wanted to hear nothing but "business as usual, carry on!" so they were bound to criticize anything short of a straight-up denier position.
LouisvilleDem
(303 posts)Not only is this not true, the answer is exactly the same as why air temperature increases were too high. In both cases, the error came from the fact that the models do not model ocean currents correctly.
http://web.b.ebscohost.com/abstract?direct=true&profile=ehost&scope=site&authtype=crawler&jrnl=19940416&AN=87613550&h=c7Omu3B0HZ37XquaQhxyFqsbpekD42Q6WF6JF0iz81MU4tgNnZMwx0W%2bAMOfAP3mzJ3KXKnnEoP7fZbWXfkcCA%3d%3d&crl=c
joshcryer
(62,287 posts)I've never seen a model so robustly defended despite that it doesn't follow the real world data.
LouisvilleDem
(303 posts)I see people here defend model projections long after those models have failed to track real world data for years.
joshcryer
(62,287 posts)joshcryer
(62,287 posts)I quote it again here:
Bill USA
(6,436 posts)Permafrost stores an immense amount of carbon and methane (twice as much carbon as contained in the atmosphere). In a warming environment, permafrost is expected to degrade, and these gases which have been in storage will be released. This process has already begun in some parts of the world, including western Siberia, and is expected to increase in earnest by the year 2020. Furthermore, as of 2011, no climate model incorporates the effects of methane released from melting permafrost, suggesting that even the most extreme climate scenarios in the models might not be extreme enough.
This is a lot to leave out. Methane, for the first 25 yrs or so (until it breaks down into CO2) has 75 times the heat trapping capacity of CO2.
also: Earth More Sensitive to Increasing Greenhouse Gas Than Thought (i.e. than climate models have been predicting)
(emphasis my own)
Earths climate may warm considerably more than expected in response to a doubling of atmospheric carbon dioxide, a new study of a broad range of climate models hints. The reason, the scientists say, is that simulations that now show only a moderate amount of warming dont accurately depict the amount of cloud formation in the lower atmosphere, thus cooling the climate more than real-world data suggest will actually occur. If true, warming of the planet will fall toward the high end of the range offered in every expert climate assessment of the past 3 decades.
~~
~~
Current models and a range of observations suggest that Earth will warm somewhere between 1.5° and 4.5°C once carbon dioxide levels are twice the preindustrial concentration of about 280 parts per million and the climate system adjusts, says Steven Sherwood, an atmospheric scientist at the University of New South Wales in Sydney, Australia. Thats a wide range, he notesa range that hasnt narrowed since the first computer simulations of climate debuted in the 1970s. Broad analyses have hinted that a models climate sensitivity depends, in large part, on how the model estimates cloud formation at low altitude, he adds. If a simulation produces generous amounts of low-level clouds, more sunlight is reflected back into space, and Earth, on the whole, is cooler than it would have been without the clouds.
In an attempt to narrow the range of climate sensitivity, Sherwood and his colleagues analyzed the results from 43 different climate models. Specifically, they looked at how the simulations represented mixing in the lowest few kilometers of the atmosphere, where many clouds form, as climate gets warmer. Then, they compared model results with data gathered worldwide.
The team found that on the whole, the global climate models with low climate sensitivityall 15 of those in which global average temperature rose less than 3°C for each doubling of CO2produced far too many low-altitude clouds. These [low-sensitivity] models are doing it all wrong, Sherwood says. On the whole, he and his colleagues say, increased convection in the lowest portion of the atmosphere will tend to dry out the air there, making cloud formation less likely. That, in turn, suggests that the low-sensitivity models shouldnt be trusted, and that Earth will most likely warm more than 3°C for each doubling of CO2, the researchers report in todays issue of Nature.
(more)
as a linear, straight-line function also inflates the available carbon budget by some 10 years
worth of emissions at the current rate."
.....I've always considered the representation of GW as a linear phenomenon bizarre. Ever since they first started making predictions of temperature change they have had to revise their predictions as actual measurements consistently came in above the estimates. Refining the models and cleaning up data is part of the picture, but didn't anybody consider that it's not a linear phenomenon??? ... it's a curvilinear phenomenon.
There are many people who say they accept the fact that the Earth is experiencing AGW but nonetheless, still think we've got a several decades to gradually reduce GHG emissions. Thus we will languidly pass the 'event horizon' of GW (if we haven't passed it already) as we proceed at a very measured pace of reduction of GHG emissions.
recommended!
joshcryer
(62,287 posts)If the permafrost melts the arctic melts for a significant period of time, which causes a feedback loop. It's not good, not good at all.
CRH
(1,553 posts)to review AR4, before he disagreed with this very subject, climate sensitivity. He was then considered best left out of the 'official' reviewers. ( aka. , blackballed ).
Look at David Wasdell's history, and academia, and his papers, view his demeanor, then imagine him to be anything other than genuine. Add in confirmation, with anything Peter Wadhams' has written; and you find a barrier that must make you question, the official political rag, I.E., the IPCC.
If not, have a good day.
on edit: correct transposition.