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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 27101 to 27150:

michael sweet at 20:19 PM on 26 October 2015

2015 SkS Weekly Digest #43

I teach High School in Tampa, Florida. Every year at this time I assign a writing assignment where students read the NSIDC summary of the Arctic Sea Ice melt season (located here, scroll past the Antarctic summary). I just finished reading the reports.

I received about 53 reports from my AP Chemistry students. They are 11th and 12th graders. They are the best students in the school. This year 2 students said that they were aware of the melting sea ice situation before they wrote their report, one of those students had written the same report for me two years ago. One student who had written the report two years ago said they had never heard of the sea ice melting. (about 5 students had me two years ago).

This year only one student suggested that the melting ice is not a problem. Students may slant their reports since they know I feel strongly about the subject. 6 or 7 years ago it was much more common for students to say AGW was no problem or a hoax, at least 10% of students (unfortunately never counted). For the past three years few students say AGW is a hoax and only one or two per class strongly question AGW.

Selected comments (they are required to say something they learned):

"I learned that Global Warming is, in fact, not a myth, and that there is numerical data to support that."

"Before this I didn't really think Global Warmiing existed but now, from the data, I can see that it really does exist".

"I had no idea of the problem"

"I was very shocked to find out just how much [sea ice] had been lost over the years".

"I knew [Global Warming] was a problem, but I was unaware that it was that big of a problem ...I learned that Global Warming is not a myth, but that it is a reality affecting us now, and will continue to be a problem in the future".

"I had no prior knowledge regarding Arctic Sea Ice ... this is the first evidence of [global warmng] that I have ever really seen, and it is quite shocking".

[From this report] "I learned that decreasing ice levels can have bad effects on the Earth's environment"

"Is this normal, I am a vegan and I did not know this."

[The decrease] "suprised me, I did not think it was so drastic."

"I learned the Arctic Sea ice was melting more than most people, including me, were aware of."

Students frequently call for more research to determine if this is normal and what is the cause. They say we should do something if it turns out to be caused by humans. They are concerned this might be a problem for future generations and worry about their grandchildren. Many students this year acknowledged AGW and suggested action should be taken immediately.

I have my students do another report in January about the NOAA temperature data. That should be interesting this year. Sorry for the long post.

Tom Curtis at 12:41 PM on 26 October 2015

Climate sensitivity is low

psagar @365, the IR flux from the top of the atmosphere is a function of Global Mean Surface Temperature (GMST), not of how much heat is stored at the Earth's surface. Therefore, as a forcing is an imbalance in the Top Of Atmosphere (TOA) energy flux, to restore equilibrium with a change of forcing requires a change of GMST. No amount of change in Ocean Heat Content (OHC) by itself will have any effect on that.

Of course, change in heat content is related to change in temperature by the heat capacity. Therefore, increasing the OHC will also increase GMST. That increase, however, will continue until the TOA imbalance is eliminated, which is to say, until the change in GMST causes a change in OLR sufficient to compensate for the original forcing and any consequent changes as a result of feedback. The difference the effective heat capacity of the system makes is that the larger the capacity, the more heat must be pumped into the ocean for the same rise in GMST.

So, turning to the relationship between Transient Climate Response (TCR) and Equilibrium Climate Sensitivity (ECS). Technically the TCR is the temperature after 70 years of increasing CO2 concentration by 1% per annum (ie, at the time the CO2 concentration reaches twice the initial value). The ECS is the temperature after the CO2 is doubled and the temperature stops changing (ignoring slow feedbacks). Typically that is about 200 years after the CO2 reaches 2 times its initial concentration, although it varies from model to model depending on the effective heat capacity of the Earth's surface in the model. The smaller the effective heat capacity, the more rapidly will the model reach equilibrium, and the closer TCR will be to ECS.

In the real world, the TCR is a close approximation to the immediate temperature response to a slow forcing change. Thus we can treat the TCR is the current mean decadal temperaure divided by the current forcing and multiplied by 3.7 W/m^2 (ie, the forcing for doubled CO2). However, as the TOA energy imbalance currently is about 0.8 W/m^2, we clearly are not yet at equilibrium even though we are, by the approximation above, at the TCR for the current forcing. As closing that imbalance requires increasing GMST, it follows that ECS > TCR in real life, and not just in the models. As an aside, ECS cannot be less than TCR by virtue of the definitions of the terms, and will only equal TCR if the effective heat capacity of the Earth's surface closely approximates to zero.

psagar at 08:55 AM on 26 October 2015

Climate sensitivity is low

The wikipedia article on Climate Sensitivity states that the transient climate sensitivity is lower than equilibrium climate sensitivity which I do not quite understand. By definition, climate sensitivity is the change in surface temperature per unit change in radiative forcing. As I understand, climate sensitivity can be obtained both from models and observations. Lets talk about models' climate sensitivity. In models, the ocean heat uptake is not quite well represented in transient simulations while in long term simulations (assuming that model reaches equilibrium), ocean heat uptake may be well represented. So in long term model simulations, one would expect that the surface temperature change per unit change in radiative forcing would be lower because the heat would be well mixed in the ocean as compared to transient simulations. Am I missing something? Could anyone comment on this?

nigelj at 07:43 AM on 26 October 2015

Tracking the 2C Limit - September 2015

"until we're far enough past the El Nino that they can restart the "it hasn't warmed since 2016..." schtick."

That particular sceptical argument has been used to saturation, and wont work any more.

It will be on to "CO2 is plantfood".

NORCALGUY101 at 06:48 AM on 26 October 2015

It's the sun

I find this article intresting since it pre-dates post NASA's prediction in May of 2006 that the sun was about to go into a state of lower solar sunspot activity.

Now just in July at the National Astronomy Meeting in Llandudno, Wales, Professor Valentina Zharkova presented an argument that due to the sinusodal period of the dynomo effects within two layers of the sun thgat have been quited accurately observed and predicted, will essentially cancel oneanother out by 2030 placing the sun in a lower state of inactivity than present and could very well spell another "mini ice age" Maunder Minimum event. We shall soon see.

Moderator Response:

[TD] There are many things wrong with that news story about Zharkova you are relying on. Read the relevant SkS post and comment there, please.

Rob Honeycutt at 23:50 PM on 25 October 2015

Tracking the 2C Limit - September 2015

TonyW... The 1880-1909 baseline is the closest to preindustrial that I can get just using the GISS data. Part of my reasoning for posting this on SkS every month is to get people thinking about where we actually are relative to preindustrial. I hope climate researchers eventually come up with a better estimation of a preindustrial baseline that could be used across all the data sets.

TonyW at 16:40 PM on 25 October 2015

Tracking the 2C Limit - September 2015

By the way, Rob, I was confused by the term "baseline", in the article. First you talked about a pre-industrial baseline but the graph gives the baseline as the period 1880-1909. That wouldn't be pre-industrial. Is there a further adjustment to be made for true pre-industrial (which would presumably be a 30 year period centred on 1750)?

James Hansen (and others) regard 1C as the dangerous warming level. It seems we're already past the dangerous level, if the extra adjustment doesn't amend 1.062C downwards. It's getting interesting.

TonyW at 16:34 PM on 25 October 2015

Tracking the 2C Limit - September 2015

Tamino examined various datasets, including RSS, in this post. It certainly looks as though "something happened" around 2000, to send the RSS data off, relative to actual surface temperature measurements. It would be great to get some serious research into the satellite data sets to see why they diverge from that time. Maybe there is something we don't yet know about the lower troposphere (though Tamino's post also shows radiosonde data doesn't appear to go off track at 2000. My guess (worth nothing, of course) is that the calculations were thrown off in 2000, and this hasn't yet been picked up.

Longjohn, two warmest years in a row would not be unprecedented. I think it's often forgotten that 1997 was the warmest year on record, at the time. Then 1998 eclipsed it, by some margin. Looks like a similar thing is going to happen this time, though 2016 will be very interesting.

kymhorsell at 15:20 PM on 25 October 2015

Accumulated Cyclone Energy Questions and Answers

OK, I've come to this quite late.

I've just started looking at ACE values.

My background is in data science and not "real" science, so I've found a trend in global ACE over time using some simple methods. Perhaps too simple.

I was wondering what is the EXPECTED change to global ACE for a gradual change in surface temps of say 1C.

I can see via various means an estimate of a very transient change can be obtained using seasonal variations in ACE/surf temps. But that — of course — gets an expected change in ACE per deg C that is quite large.

I'm looking for a "fudge factor" more than anything else, that might account for buffering effects that might give a ballpark equilibrium change in ACE for a 1C change in surf temps.

Any ideas?

Bob Loblaw at 07:27 AM on 25 October 2015

Tracking the 2C Limit - September 2015

...until we're far enough past the El Nino that they can restart the "it hasn't warmed since 2016..." schtick.

Rob Honeycutt at 01:44 AM on 25 October 2015

Tracking the 2C Limit - September 2015

I'm expecting the "no warming since..." to turn into "it's just el nino."

longjohn119 at 00:45 AM on 25 October 2015

Tracking the 2C Limit - September 2015

As Cooper13 noted the atmospheric heat came on the downside of the '97-'98 el Nino

We are already on track to set an unprecendented global temperature record two years in a row and I submit that 2016 could very well make it 3 straight years or at least the top 3 years all in a row but not necessarily in order

That should quell the "It stopped warming in blah, blah, blah" Myth but likely it won't .... Denial is seldom overcome by facts and Reality

Tom Curtis at 21:17 PM on 24 October 2015

Other planets are warming

Bi5h0p argument turns out on examination to be an appeal to changes in cosmic ray frequencies as a driver of climate. Consequently, I have responded on a more appropriate thread. On the unsubstantive diatribe with which he begins, Phillipe Chantreau @37 raises the relevant question.

Tom Curtis at 21:12 PM on 24 October 2015

It's cosmic rays

Elsewhere Bi5h0p presents an argument that is off topic there, and on topic here. Specifically they say:

"So, if the Sun has such a major impact on the Earth's weather, how much more does our own galactic weather have on our Sun and it's solar system? It's reasonable to hypothesize that galactic weather could have a much greater effect on the solar system, as a whole, during certain galactic weather events. Our solar system is travelling through an interstellar medium, the density and energy of which may vary greatly - and for extended periods of time. This could also explain any other planetary changes which have been, or may have been observed as every object in our solar system could be impacted by such events."

In support of this, they link to a conservative "news" site that is stong on pseudoscience, and in particular to a 2012 article that claims that:

1) Two professors have discovered new particles reaching Earth from galactic center; and

2) That some unknown particle from the Sun causes variations in the rate of nuclear decay.

With regard to (1) it is hard to comment. At the time of publication of the article, the professor's work has been "submitted to the peer-reviewed American Physical Society journal Physical Review" as of 2012, but of which I can find no sign three years later. Because I cannot find a source paper, all I an say is that nothing in the report from "beforeitsnews" implies either new particles, or new energy intensities. Indeed, at most it seems to imply that the professors have better localized the source of already observed cosmic rays.

With regard to (2), the report is of actual peer reviewed papers that have not been consistently confirmed by later observations. That is, it is still possible that there is no such effect. Further, it is presently conjectured that if the effect is real, it is caused by neutrinos rather than as yet unobserved (and untheorized) mystery particles.

With regard to climate, if real, the effect only applies to beta particle decay (ie, the conversion of protons to neutrons by the emission of a neutrino and an electron, or of neutrons to protons by the emission of a neutrino and a positron). As such, it has minimal imact, if any, on geophysical heat, which is primarilly based on alpha particle decay. Further, even if it did, any such impact would be long delayed and difuse due to the time it takes for heat to rise through the mantle and crust. Finally, and most importantly, newly discovered does not mean recently started. If the ambiguous support for this phenomenon turns out to be accurate, that only means that an effect that has been in existence for the enirety of the Earth's existence will have been newly discovered. Ergo, it implies no change in heatflow, and hence no change in climate.

You will notice that neither (1) nor (2) have any bearing on "galactic weather". Nevertheless I did find websites discussing the above phenomenon which also drew attention to a NASA press release drawing attention to a newly discovered interstellar magnetic field. The magnetic field is associated with the local interstellar cloud, and when the Sun exits the local interstellar cloud, this could result in a different strength of the interstellar magnetic field, and hence a change in the number of galactic cosmic rays reaching the Earth. As the news release says:

"The fact that the Fluff is strongly magnetized means that other clouds in the galactic neighborhood could be, too. Eventually, the solar system will run into some of them, and their strong magnetic fields could compress the heliosphere even more than it is compressed now. Additional compression could allow more cosmic rays to reach the inner solar system, possibly affecting terrestrial climate and the ability of astronauts to travel safely through space. On the other hand, astronauts wouldn't have to travel so far because interstellar space would be closer than ever. These events would play out on time scales of tens to hundreds of thousands of years, which is how long it takes for the solar system to move from one cloud to the next."
(My emphasis)

Completely ignoring the highlighted statement, the pseudoscientific sites trying to sell this phenomenon as a cause of recent climate change suggest the Sun has only just recently entered the local cloud, perhaps encouraged by the illustration below.

They have paid not attention, however, to the relative distances involved. A recent mapping of the structure and velocities of the local cloud shows that the most recent time in which the Sun could have entered the local cloud (based on relative velocity and the lower bound estimate of the closest cloud surface) was ten thousand years ago. Even if we allow that cosmic rays effect climate (and it is very dubious that they have a major effect, as detailed in the OP above), this change occured 10 or more thousand years ago, and is certainly not the cause of the rise in temperature in the 20th century.

In sum, the evidence Bi5h0p relies upon is (at best) a beat up of far more mundane facts, presented breathlessly, inaccurately, and treated as certainties despite the highly qualified nature of the actual reports. This tissue of distortion, misrepresentations on uncertain basis is then presented as better than the very well established facts of climate science.

MA Rodger at 20:22 PM on 24 October 2015

Other planets are warming

5i5h0p @36.

Your link dates from 2012 and is wrtten in particularly sensational language, usually a bit of a give-away with such publication. It quotes only three scientists (It is not always the wisest thing to rely on very small numbers of scientists. Remember the phrase “There's always one” and with scientists that is certainly the case.) and your link is actually mashing four different phenomenon and three separate issues rolled into the one account.

The first is gamma-ray emissions from the centre of our galaxy. The news is that that Profs Abazajian & Kapling have “patiently sifted through reams of data accumulated from 2008 to 2012 by NASA’s orbiting Fermi Gamma-ray Space Telescope” and now (in 2012) propose that the gamma-rays streaming from the stellar conflagration can be used to infer the presence of dark matter.

On this first issue, with no change in this phenomenon there can be no change resulting on planet Earth. There is no new situation being discussed, just the measuring of something in more detail than before. It is also very new science (as written it had yet to pass peer review and I see no sign of publication today) so should not be accepted from what is just one 'paper in submission'.

The second issue is down to a lunatic called Dr. Alexey N. Dmitriev who has been preaching for some time (This reference date 1998) of a coming armagedon resulting from “highly charged material and energetic non-uniformities in anisotropic interstellar space which have broken into the interplanetary area of our Solar System.” If Dmitriev hasn't managed to convince his fellow scientists in (2015-1998=) 18 years, it likely isn't worth examining the details of his assertions and rather put it down to “There's always one!”

The third issue is very poorly described and presented most sensationally. It is referenced only by use of a NASA quote “once in a lifetime super solar storm event” that apparently dates to March 2006 (the NASA archive links to this are not providing any text at present) and is about the 11-year solar cycle which (No 24) was soon to begin in 2006. With a lot more satellite use since the height of the previous solar cycle, NASA was warning of potential problems from the coming cycle. This does not stop the nutters deciding the warning is about something completely different. Indeed, the only uses of that quote on-line actually discusses, not 11-year solar cycles but instead the rotation of our bit of the Milky Way around the centre of the galaxy. The quote is thus exclusively used by a bunch of real nutters who predict the end of the world. Whether the result will be ”thousands of rocks and asteriods … raining out of the sky” or a “rampage” of “powerful x-class solar storms and coronal mass ejections”, we are apparently in danger of “great earthquakes, super volcanic eruptions, pole shifts, planet crossers and so forth” and that is despite acknowledging that the peak storms of 2012-13 are now passed. All this has zero credibility.

So I conclude that on all three issues mentioned by your link, there is nothing that requires fresh investigations.

PhilippeChantreau at 16:00 PM on 24 October 2015

Other planets are warming

Bi5h0p,

I am straining how you can give the appearance of being rational and acknowledge your superficial understanding of a scientific subject matter while at the same throwing out an opinion that dismisses an entire body of knowledge as, also, mere opinion. A body of knowledge with which you have confessed lack of familiarity. How does that make any sense?

As far as the rest of your questions, there is a start here button on the site that you should use to start exploring.

I'll add that not everything is a matter of point of view. There is a right answer. Uninformed opinions carry no validity whatsoever against those formed by the understanding of the scientific issues involved. It really is that simple. If you want to form a opinion worth its salt, you have to do the work. If you don't, you'll just say whatever suits your already existing system of belief and values, or parrot other sources that you recognoze as sharing that same system. That's worth somewhere between a rabitt's fart and a mouse turd on the scale of reality based understanding. The internet contains the best and the worst. Why do you trust the source you cited?

I tried your link, it didn't load for me; I couldnt' evaluate whether they cited any scientific work and how faithful to the original content it was. It appears to be about galactic cosmic rays (GCRs). That's old news and there is a number of threads exploring the question on this site. Use the search engine. CERN has experimented on the subject and they do have info available online. Do your work. Don't expect people to spoon feed you the info. Select serious sources. Examine published science papers. If a blurb mentions a science article, read it, as many cite a paper and draw from it conclusions that are often nowhere near what the authors conclude or even say. That's how it works.

Bi5h0p at 13:55 PM on 24 October 2015

Other planets are warming

(This is my first post ever in this forum so please, bear with me if I break some cardinal rule. But, please point it out to me.)

First off, I'm not formally educated about any of these topics - cosmology is more of a point of interest or a hobby for me. I approach all of this in fairly broad strokes.

"Climate Warming," now re-fashioned into, "Climate Change," seems to be very little based on science and much more related to your political philosophy nowdays. It is a good excuse to raise taxes and place further controls on the entire planet, for those in power. I honestly don't really have an opinion on all of that, one way or the other, except for my own brief lifetime.

Personally, I do think that the planet is becoming more turbulent, and I don't think mankind has done anything to help the situation. There is no doubt that human industry, war, nuclear testing, pollution, deforestation, etc. have damaged our ecosystems - just a debate over the degree to which we have damaged things. I agree with what I think was the OP's original assertion that the Sun's weather is, by far, the greatest determinant of weather on the Earth. That being said, the Earth's environment, it's "goldielocks" position in the universe being just right, I don't think it takes much to knock things way out of balance - say, a .02% change in the amount of CO2 in the atmosphere. Things could be more delicate than most of us realize.

So, if the Sun has such a major impact on the Earth's weather, how much more does our own galactic weather have on our Sun and it's solar system? It's reasonable to hypothesize that galactic weather could have a much greater effect on the solar system, as a whole, during certain galactic weather events. Our solar system is travelling through an interstellar medium, the density and energy of which may vary greatly - and for extended periods of time. This could also explain any other planetary changes which have been, or may have been observed as every object in our solar system could be impacted by such events.

So, here is a link to a site which explains the phenomenon in greater detail than I ever could:

http://beforeitsnews.com/space/2012/09/strange-energy-from-galactic-center-bombarding-earth-2446172.html

I hope this adds something to the discussion - another point of view which may not have been investigated yet.

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