Arguments
Sun & climate: moving in opposite directions
What the science says...
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The sun's energy has decreased since the 1980s but the Earth keeps warming faster than before. |
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Climate Myth...
It's the sun
"Over the past few hundred years, there has been a steady increase in the numbers of sunspots, at the time when the Earth has been getting warmer. The data suggests solar activity is influencing the global climate causing the world to get warmer." (BBC)
Over the last 35 years the sun has shown a cooling trend. However global temperatures continue to increase. If the sun's energy is decreasing while the Earth is warming, then the sun can't be the main control of the temperature.
Figure 1 shows the trend in global temperature compared to changes in the amount of solar energy that hits the Earth. The sun's energy fluctuates on a cycle that's about 11 years long. The energy changes by about 0.1% on each cycle. If the Earth's temperature was controlled mainly by the sun, then it should have cooled between 2000 and 2008.
Figure 1: Annual global temperature change (thin light red) with 11 year moving average of temperature (thick dark red). Temperature from NASA GISS. Annual Total Solar Irradiance (thin light blue) with 11 year moving average of TSI (thick dark blue). TSI from 1880 to 1978 from Krivova et al 2007. TSI from 1979 to 2015 from the World Radiation Center (see their PMOD index page for data updates). Plots of the most recent solar irradiance can be found at the Laboratory for Atmospheric and Space Physics LISIRD site.
The solar fluctuations since 1870 have contributed a maximum of 0.1 °C to temperature changes. In recent times the biggest solar fluctuation happened around 1960. But the fastest global warming started in 1980.
Figure 2 shows how much different factors have contributed recent warming. It compares the contributions from the sun, volcanoes, El Niño and greenhouse gases. The sun adds 0.02 to 0.1 °C. Volcanoes cool the Earth by 0.1-0.2 °C. Natural variability (like El Niño) heats or cools by about 0.1-0.2 °C. Greenhouse gases have heated the climate by over 0.8 °C.
Figure 2 Global surface temperature anomalies from 1870 to 2010, and the natural (solar, volcanic, and internal) and anthropogenic factors that influence them. (a) Global surface temperature record (1870–2010) relative to the average global surface temperature for 1961–1990 (black line). A model of global surface temperature change (a: red line) produced using the sum of the impacts on temperature of natural (b, c, d) and anthropogenic factors (e). (b) Estimated temperature response to solar forcing. (c) Estimated temperature response to volcanic eruptions. (d) Estimated temperature variability due to internal variability, here related to the El Niño-Southern Oscillation. (e) Estimated temperature response to anthropogenic forcing, consisting of a warming component from greenhouse gases, and a cooling component from most aerosols. (IPCC AR5, Chap 5)
Some people try to blame the sun for the current rise in temperatures by cherry picking the data. They only show data from periods when sun and climate data track together. They draw a false conclusion by ignoring the last few decades when the data shows the opposite result.
Basic rebuttal written by Larry M, updated by Sarah
Update July 2015:
Here is a related lecture-video from Denial101x - Making Sense of Climate Science Denial
Last updated on 2 April 2017 by Sarah. View Archives
I understand you have preented data comparing CO2 to surface temps, but that is not what I asked.
Since the Daleks took my time machine back to rescue the Morlocks from the Eloi,
from Beer et al, 2006: Perusual of the various versions of this post, plus the graphs I showed you in My Previous Comment #749 reveal the tight relationship between solar variability, CO2 and temperatures (with temperatures being merely the composite sum of forcings and feedbacks) in the paleo record.
The unusual climatic stability of the Holocene:
So my questions to you, TheCaz: looking at the record of CO2 over the past 400,000 years or so (here, I'll help with a visual):
When did atmospheric concentration jump 40% (which it has over the pre-industrial levels)? At any point? Do you see any uncouplings? Keep in mind that CO2 in the paleo record acted as a lagged feedback to orbital factors and solar irradiance changes. And that it is now acting as a forcing.
Or do you have a source for solar activity over the paleo record that materially differs from the information presented in the various iterations of this post, my comments and linked sources? If so, what source is that? Can you furnish a link?
The Yooper
I understand temps and CO2 are uncoupled, but I was asking about solar activity and surface temps. Is the recent uncoupling unique in the holocene?
I do not have the data myself. That is why I am asking the question.
Daniel gave you an example of solar reconstructions for the Holocene in his link to Beer et al, 2006.
Specifically figure 2 panel c appears to be what you are looking for.
But the paper does give something of an answer elsewhere. It says before the launching of satellites, solar activity could not be measured. So that is the answer I was looking for - "We do not know."
The paper says the sun has activity cycles, but then assumes those cycles are regular. The author uses this to exclude solar activity variation as causative in the long term. We now know this is incorrect. In fact, the graph at the top of this page shows that solar activity (11-year averages) has varied over the past 130 years.
Sorry I pointed you to the wrong section, the paper does go on to detail a solar activity proxy as you discovered.
Thus, it's not the sun. It's CO2.
"Solar variation did not cause the 78 – 98 warming but it can cause the 1880 to 2010 trend"
Barring the obvious fact that 78-98 are contained in 1880-2010, there is no evidence for this 'solar cause'. Sunspot numbers correlate well with satellite measures of solar irradiance and the reconstructions of solar output don't support it. If anything, the sun's relatively quiet behavior in recent years should have a cooling effect; yet we know that 2000-2009 was one of the hottest 10 year period in the last 6 decades.
We've been through the cosmic ray discussion many times. There is no consistent evidence of any such effect.
"the cooling would not be instant due to thermal inertia (i.e. the ocean is storing the cooling)"
The solar max occurred in the late 50s. Sixty years later, still no cooling. And for your own benefit, please don't ever say something 'stores cooling' in any public forum. It's like asking what is the speed of darkness?
And you can't have the speed of darkness without the Sound of Silence
By 2012, when the sun is really cookin' and the Arctic ice recedes from the pole for the first time in unknown millennia, enquiring minds will want to know: Just how did those Mayans know?
I bet this thread hits 1,000 comments before spring...
The Yooper
Sucker bet on hitting the thou. If I took it, all you'd need to do is drop the words 'climate sensitivity' in here.
If we say "waste heat" we'll draw a cool mill...then John could charge admission & make this site a revenue source instead of sink...
The Yooper
Lockwood 2010 Solar change and climate: an update in the light of the current exceptional solar minimum is an interesting summary paper for the Royal Society.
By way of introduction,
The Internet has played a useful role in conveying some of the understanding, images and data that lead climate scientists to their conclusions. However, it has also become a haven for un-refereed pseudo-science with dangerously incorrect inference. It has served to give the false impression that there is a serious, widespread academic debate on the basic nature of climate change. The most popular argument runs like this: ‘The Sun drives Earth’s climate system. Therefore changes in the Sun must drive changes in Earth’s climate system’. The first sentence is, of course, absolutely correct; but understanding why the second sentence does not follow from the first requires scientific training and study. --emphasis added
The remainder of the paper is a thorough treatment of solar variation, concluding with
... the popular idea (at least on the Internet and in some parts of the media) that solar changes are some kind of alternative to GHG forcing in explaining the rise in surface temperatures has no credibility with almost all climate scientists.
Sounds like he's got his head on straight.
A combination of the increased TSI and UV may explain up to 0.44 degrees of the 0.55 degree HADCRU warming - 80%.
"A peer-reviewed paper [Krivova et al.] published in the Journal of Geophysical Research finds that reconstructions of total solar irradiance (TSI) show a significant increase since the Maunder minimum in the 1600's during the Little Ice Age and shows further increases over the 19th and 20th centuries.....Use of the Stefan-Boltzmann equation indicates that a 1.25 W/m2 increase in solar activity could account for an approximate .44C global temperature increase.....A significant new finding is that portions of the more energetic ultraviolet region of the solar spectrum increased by almost 50% over the 400 years since the Maunder minimum.....This is highly significant because the UV portion of the solar spectrum is the most important for heating of the oceans due to the greatest penetration beyond the surface and highest energy levels. Solar UV is capable of penetrating the ocean to depths of several meters to cause ocean heating." [N. A. Krivova, L. E. A. Vieira, S. K. Solanki 2010: Journal of Geophysical Research, Vol. 115, A12112, 11 PP., 2010 doi:10.1029/2010JA015431
Figures 5 and 6 in the paper (pdf here) clearly show the solar UV max coincident with the late '50s 'grand maximum'. That suggests that in the 50 years since, the 4 subsequent solar maxima were flat to lower than this well-known peak. That's the key point in this post: between the 1960s and the present day the same solar measurements have shown that the energy from the sun is now decreasing.
See the graph at the top of the page.
On another note, when I was in the awl bidness, we referred to Mother Exxon as 'the double cross' - and that was before the Valdez.
Update: here is a couple of figures showing the latest (corrected) data on energy content of the oceans (one together with GISS-projections).
http://i47.tinypic.com/20kvhwn.png
http://www.nodc.noaa.gov/OC5/3M_HEAT_CONTENT/index.html
Figure 5 in the Krivova paper is a graph of UV flux vs. time. In order to represent increasing energy, the area under the curve must increase: either the peaks must be bigger or the width (time duration) of the peaks are broader. The largest peak UV was in 1958 and the time duration of the subsequent cycles is the standard 10-11 years. What part of that is clearly demonstrating your point?
If you are saying that the cumulative energy summed over all cycles is increasing, that's obvious. But that sum is not a measure of the energy balance at TOA or in the oceans.
Here are the author's conclusions:
... since the LTE approximation underlies the computations of the brightness spectra of different photospheric components, the original version of the model fails in the UV. Although it contributes little to the total irradiance (such that the modelled TSI is nevertheless quite accurate), this wavelegth range on its own is of special interest for climate research due to its important influence on the chemistry and dynamics of the Earth’s atmosphere ... -- emphasis added
There is no mention of UV contributing to ocean heating. Their "value of about 1.25 W/m2 as our best estimate for the 11-yr averaged increase in the TSI between the end of the Maunder minimum and the end of the 20th century, compared to 1.3 W/m2 derived by Balmaceda et al. [2007] and Krivova et al. [2007]" doesn't specifically say that it increased through the end of the century.
Further discussion specific to ocean heat content should go here.
But cycle 24 looks similar to cycles 5 and 6, during the Dalton Minumum. It's still too early to say for sure but it is possible that a weak cycle 24 may lead to subsequent global cooling.
As for a decrease in solar activity trumping the enhanced greenhouse effect, please use the search box to find the article on what would happen if the Sun returned to Maunder Minimum activity levels.
Yep. See Deep solar minimum (from 2009) which reports:
A 50-year low in solar wind pressure
A 12-year low in solar "irradiance"
A 55-year low in solar radio emissions
and type in 1900.5 to 2009.5. The historical TSI reconstruction shows five 11-year solar cycles between 1900-1950 and five between 1955-2005. Clearly, the five cycles after 1950 were more active than the five pre-1950 cycles.
I agree that cycle 24 is unusually quiet and supports my thesis that the Sun does influence global surface temperatures. In this case, if cycle 24 is longer and weaker than previous (21-23), then we may see subsequent global cooling in response.
It's interesting to note that the solar max in 1970 (cycle 20) was relatively weak. I remember the "Big Freeze" in 1977 when the Chesapeake Bay froze over.
See What would happen if the sun fell to Maunder Minimum levels, and also the comparative values of forcings here - I find Figure 2a very clear. I believe you've been pointed to these items previously.
Global cooling? No. Warming perhaps a little slower if solar variation reaches a low? Yes.
Thank you for such a wonderful example of circular reasoning in climate science. Not to mention that irradiance variations in the UV are not represented. And what is the uncertainty in the temperature predictions? Let's be reasonable, the atmospheric response to CO2 doubling may be (0.5 C), See Lindzen and Choi. Even the lower range of the IPCC CO2 doubling (2 C) is too high. Talk about over-forecasting. What do they say in meteorology? I think that your forecast is a bust.
How is this circular? Assumptions for model inputs are required to run the models. The question tested is one aspect of the model -- the change in solar activity (On the effect of a new grand min is part of the title) in the presence of other forcings.
Lindzen and Choi have been dealt with elsewhere ad nauseum. Here's a bit of free advice: Don't cite a source without checking to see if its been rebutted. I learned that one the hard way, back in the days of oral exams.
Multiple lines of reasoning, including both model runs that accurately reproduce past climate behavior, as well as empirical evidence such as seasonal swings and historic data, all point to a sensitivity of 2 to 4.5°C, most likely 3°C.
So - going with a dis-proven outlier whose results agree with "business as usual"? Or considering that a lot of very smart people agree on a particular range? Personally, I consider the former to be wishful thinking... your mileage may vary.
As to circular reasoning, finding problems with Lindzen's 2009 approach does not address the problems with Feulner and Rahmstorf, assuming the conclusions in the premises. How about the uncertainty in the 2100 temperature predictions? How about the NASA study, the Sun does contribute to global warming, 25%. I still think that your predictions are a bust based on the surface record to date. And "business as usual" is a very important point, but it is off-topic here and best left unsaid.
Improved measurements of Sun to advance understanding of climate change
The article details the launch of a new satellite to more accurately measure total solar irradience so that better calculations can be made as to how much the Sun either does or does not contribute to the changing climate. From a selfish point of view, it should help astronomers better understand the Standard Solar Model which has some faults to it and thus enable us to get a better and more accurate model of the Sun, which would also help climate forecasting.
We are well aware of ongoing efforts to better understand solar astronomy. Did you have point beyond asserting we just aren't as up-to-speed as you?
I have a friend who constantly bangs on about Piers Corbyn and his site ‘Climate Action’. Sadly I have very little time to research Corbyn’s claims. I was wondering if anyone has analysed Corbyn’s weather predictions comparing them to the main weather predictions of places like the met office and also his claims about making money by placing bets on future weather. I know this is about weather but Piers definitely believes AGW is a myth. Could someone look into his claims and perhaps do an article on him. There seems to be very little objective research done on his claims... that I can find anyway. We have Monckton Myths how about Corbyn’s Crocks? I posted here because I know Corbyn thinks its all about the sun.
However, he hasn't been doing so good this year, as the following forecasts show :
December 09: Wet and windy start giving way to severe
Arctic blasts with heavy snow and blizzards in parts.
Turning mild or very mild later – a ‘green’ Christmas
before colder year end.
I recall December being very cold, the coldest in a hundred years or something, but still he got it wrong.
Ferocious and dangerous winter weather [for January 2011]
Um, quite the opposite actually.
[February] Overall much colder than normal with snowy Northerly / Easterly blasts at times
Well, not so far, anyway but who is going to rely on that being correct...except by accident !
Jan AND Feb will be unusually cold in Britain, Ireland, & Europe
Maybe I've been lucky not to have experienced any of that here in London ?
Generally, the tone of his 'scientific predictions' and his website can be surmised from the following text, taken directly from the source :
Constant references to 'ClimateGate News'
● ‘Global Warming’ forecasts will fail AGAIN.
● ‘Man Made Climate Change’ is failed science based on fraudulent data
● Gordon Brown & all politicians, please, PROVE IT or DROP IT
● 2010 is the year of the fight for evidence based science & policy
● Carbon Trading & all CO2 reduction schemes must stop.
● ‘Warmers’ flee from challenge to present evidence for CO2 case.
● CO2 theory lies refuted by science fact
● ‘Man Made Climate Change’ scam now ignominiously doomed
Hmmm...
Take that same monthly series that I linked from NOAA and plot it on a graph. You see the series rise and fall the ~4C that you state. But read the rest of the page. This data is the basis for the anomaly. As the the planet warms that same series you plotted is moving upward.
All the datasets plot this. UAH, RSS, GISS, CRU... They are all taking this annual cycle into account.
"Explain the warmer July to me without using geography. ... if accurate, it does prove that geography plays a very strong role in global temperature."
That's hardly an adequate 'proof.' But let's play with it anyway. Here's something that doesn't appeal to geography: Your statement 'the earth gets more energy in winter than in summer' clearly refers only to incoming solar radiation. It is certainly true that the peak value of solar insolation averaged across all latitudes at the time of perihelion (winter) is 7% greater than at aphelion (in summer), but isn't that primarily because the earth is closer to the sun in winter?
However, basic Physical Geography (the name of textbooks, not part of the explanation) gives the control on temperature as the net radiation: the sum of incoming (daytime) and outgoing (nighttime). For example, this is London:
--from physicalgeography.net
During the winter months, outgoing longwave radiation actually exceeds incoming insolation producing negative net radiation values.
The linked page gives examples for several other locations.
So when length of day is taken into account, the 7% additional energy 'received' in winter is radiated away during those long winter nights; winters are colder than summer.
What they don't do is push past any of those points to fully understand the science because that endangers the conclusion they want to find.
I often see this in students. They take a position based on something they've heard (or, sadly, been told by a parent or prior teacher) and cling to it no matter what. If, after a little Socratic give-and-take, you can see their doubt level rising, you can make a difference. However, some are afraid to simply admit that they've been misinformed or are just plain wrong.
In the case of some of the most ardent skeptics, clinging to a pre-conceived notion frequently results in highly unscientific thinking -- and down goes credibility. In a case like this, realizing that net radiation is what matters leads to the next logical step: if we reduce the earth's outgoing radiation, the planet must warm. But that requires a greenhouse effect ... and that violates the pre-conceived notion. Illogical, does not compute!
This is complicated by geography, which influences the rate at which heat is transferred from the tropics to the poles. London, sitting close to a branch of the Gulf Stream, for example, will show a smaller (more negative) net radiation because it is substantially warmed by that current. Seattle would show a larger (less negative) net radiation because of the cold current of its coast (I believe). Both of these cities would show a larger net radiation in summer than, for example Moswow which would have hotter summers and cooler winters because of its inland location. In fact, overall the NH would display less of the disreprancy you indicate because of its larger land mass. That means fewer of its locations are close to the coast.
It is that fact which in fact accounts for the Earth being warmer at perihelion (the NH summer). Temperature variations are smaller in the SH because so little of its land is far from the ocean, and there is so much more ocean. The greater heat capacity results in a smaller overall seasonal fluctuation in temperature. That means the NH seasonal fluctuation dominates overall, resulting in greater warmth during the NH summer, which coincidentally is at the moment during aphelion.
I have focused more on the cycles such as ENSO which some people feel balances out once a cycle is complete, ignoring that it is the geographic distribution that determines what conditions each phase brings to a region, and thus all things are not equal, or mirror images of one another.
This should be taken into account when considering how this plays into the heating or the cooling of the oceans.
With regard to ENSO, you are neglecting the fact that ENSO involves a redistribution of heat over depth in the pacific ocean. In particular, the deep warm waters of the Pacific Warm Pool are redistributed across the surface of the tropical Pacific. Therefore, as regards to its primary nature, it balances out in terms of energy distribution.
Of course, the ocean interacts with the atmosphere through the surface, so an increased warmth at the surface should show similar feedbacks whether the cause is a change in forcing, or a redistribution of heat from the depths. Therefore we should expect a significant additional warming from El Nino events, and a significant extra cooling from La Nina events; which is what we in fact see. This contradicts denier claims of a low climate sensitivity. This additional warming (or cooling), however, will not introduce a trend to global temperatures because the same feedbacks operating in reverse will remove the additional warmth (or cooling) from an ENSO fluctuation from the atmosphere.