From the FECYT – Spanish Foundation for Science and Technology via Eurekalert comes this interesting note about solar forcing. It seems there’s a 2.3% per decade increase in solar radiation observed in Spain. Surely this is more than enough to account for the warming there? Cloud cover is said to be the issue, as Dr. Roy Spencer has previously pointed out, it only takes a small amount of cloud cover change to make a warming trend. – Anthony
Spain receives ever more solar radiation
Solar radiation in Spain has increased by 2.3% every decade since the 1980s, according to a study by researchers from the University of Girona and the Federal Institute of Technology (ETH) in Zurich. This increase is linked to the decreased presence of clouds, which has increased the amount of direct radiation reaching us from the Sun.
“The mean annual G series over Spain shows a tendency to increase during the 1985-2010 period, with a significant linear trend of + 3.9 W m-2 [2.3% more] per decade.” This is the main conclusion of a study published in the magazine ‘Global and Planetary Change‘ by researchers from the University of Girona and the Federal Institute of Technology in Zurich (ETH, Switzerland).
The season-by-season data show the same “significant” increase in solar radiation impacting the nation: + 6.5 W/m2 per decade during the summer, + 4.1 W/m2 in autumn, + 3.2 W/m2 in spring and + 1.7 W/m2 in winter.
“These data relate to global solar radiation, in other words the increase in direct radiation reaching us from the Sun plus diffuse radiation which is scattered previously by clouds, atmospheric gases and aerosols,” explains one of the authors, Arturo Sánchez-Lorenzo, currently a postdoctoral researcher at the University of Girona.
What is intriguing is that the scientists found a decrease in the diffuse component, because of which direct radiation has increased to a proportionately higher degree. Only in 1991 and 1992 did diffuse radiation rise, and this was due to the ashes from Mount Pinatubo. In general, however, we can observe a downward trend of – 2.1 W/m2 per decade between 1985 and 2010.
VIDEO: Solar radiation in Spain has increased by 2.3 percent every decade since the 1980s.Click here for more information.
“The explanation lies in the fact that in Spain the amount of cloud has decreased markedly since the 1980s – as we have ascertained through other studies – and the tropospheric aerosol load may also have decreased,” states Sánchez Lorenzo. “It seems to be very simple: fewer clouds result in higher solar radiation on the surface,” he continues.
According to the scientists, this increase may also go hand in hand with more ultraviolet rays, an excess of which presents a health risk, potentially leading to skin cancer.
More global brightening
The increase in global solar radiation is a phenomenon that has been observed in other parts of the world for almost 30 years, especially in developed countries, and it has been named “global brightening”. The fall in the diffuse component has also been observed in Central European and Eastern countries.
The team behind the study has not yet analysed the solar radiation data for 2011-2013 provided by the Spanish State Meteorological Agency, but the data from other European weather stations suggests that this brightening is still on the rise.
“Studies such as these may be of interest to the solar energy industry, especially in countries like Spain, where not only do we already have a lot of direct solar radiation but now we are getting even more,” affirms one of the other authors, Josep Calbó, who is a professor at the University of Girona.
References:
A. Sanchez-Lorenzo, J. Calbó, M. Wild. “Global and diffuse solar radiation in Spain: Building a homogeneous dataset and assessing their trends”. Global and Planetary Change 100: 343–352, 2013.
h/t to Dr. Leif Svalgaard
There are 3 important points about (aerosol seeded) cloud decreases.
1. They warm the surface and then the troposphere, although by less. The exact opposite of GHG warming. Hence the divergence between surface temperature measurements which have increased over this period, and troposphere temperatures which have increased hardly at all. Clear evidence that surface warming was not caused by GHGs.
2. They increase minimum temperatures disproportionately, especially in winter at mid to high latitudes for reasons I explain in the link below. Essentially, almost half of the increase in minimum temperatures is spurious.
3. An analysis of Australian temperatures and clouds by an Australian statistician (also documented at the link below) shows all the cloud decreases and temperature increases occur between 6 am and 12 am. This is clearly the result of decreased locally produced smoke, primarily from fires for heating and to a lesser extent cooking. And not due to any solar or galactic effect, which would not conform human routines.
http://www.bishop-hill.net/blog/2011/11/4/australian-temperatures.html
Jon says:
June 6, 2013 at 9:42 pm
I guess it’s about the position of the polar front. Spain did have huge problems a few years ago with little rain and rivers drying up. Means less low pressures(rain) and more high pressures(dry)?
Last year was a dry one, but I would not say that has been the norm in recent years. This year water reservoirs are in record levels, and also 2010 and 2011 were years with plenty of water.
Errrr, but this finding is in direct contravention to the established wisdom that the sun in dimming. I thought it was an established fact that the-evaporation rates were decreasing, due to increased aerosols and increased high altitude aviation activity (contrails).
So which is the correct data here?
http://onlinelibrary.wiley.com/doi/10.1029/2007GL031166/abstract
http://facstaff.uww.edu/travisd/pdf/jetcontrailsrecentresearch.pdf
https://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter9.pdf
http://en.wikipedia.org/wiki/Global_dimming
.
(better edition)
Errrr, but this finding is in direct contravention to the established wisdom that the sun is dimming due to atmospheric conditions. I thought it was an established fact that pan-evaporation rates were decreasing, due to increased aerosols and increased high altitude aviation activity (contrails).
So which is the correct data here?
http://onlinelibrary.wiley.com/doi/10.1029/2007GL031166/abstract
http://facstaff.uww.edu/travisd/pdf/jetcontrailsrecentresearch.pdf
https://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter9.pdf
http://en.wikipedia.org/wiki/Global_dimming
.
George E Smith : “I have no idea how clouds could produce a positive feedback. They can’t transport “heat energy” back to the surface; they can only lose it to space.”
——
If I point an IR thermometer at a cloud I get a reading of the temperature of that cloud, which must be heat energy radiated back to the surface.
Well here in Christchurch n.z.
More often than not the sunnier than normal the month is the cooler on the avg the month is.
ralfellis says:
June 7, 2013 at 1:36 am
“Errrr, but this finding is in direct contravention to the established wisdom that the sun in dimming. I thought it was an established fact that the-evaporation rates were decreasing, due to increased aerosols and increased high altitude aviation activity (contrails).
So which is the correct data here?”
As you can see even the wikipedia about global dimming says
“Global dimming is the gradual reduction in the amount of global direct irradiance at the Earth’s surface that was observed for several decades after the start of systematic measurements in the 1950s. The effect varies by location, but worldwide it has been estimated to be of the order of a 4% reduction over the three decades from 1960–1990. However, after discounting an anomaly caused by the eruption of Mount Pinatubo in 1991, a very slight reversal in the overall trend has been observed.[1]”
They must call it a “very slight reserval” as otherwise they would have to consider that sunlight, not CO2, is the driver of the recent warming.
So in Jimbo Wales’ NPOV-speak, Global Brightening is the very slight reversal of Global Dimming.
My solar pv system is producing about 25% more this year compared to last year. I think I might be a bit early for predicting a trend for the future though.
I noticed that solar-geological link has failed, so here it is again
http://www.vukcevic.talktalk.net/SSN_NAP.htm
Dr. Svalgaard will tell you that there is no such link, but it is often said by scientists that some events do not exist, since science has no adequate explanation as yet .
lsvalgaard says:
June 6, 2013 at 5:32 pm
This increase is linked to the decreased presence of clouds
So fewer and fewer clouds along with a less active sun…
——————————————————————————————————————
Yes, because a cooler sun means less evaporation over the oceans and, hence, less clouds.
Perfect match.
[trimmed at writer’s request. Mod]
Oopsie! Mod, please delete my last post.
Jon says:
June 6, 2013 at 9:42 pm
I guess it’s about the position of the polar front. Spain did have huge problems a few years ago with little rain and rivers drying up. Means less low pressures(rain) and more high pressures(dry)?
———————————————————————————————————
The last winter was the wettest in decades in Spain. At times, they got even more precipitation than we here in Germany did.
Some say, the Jet Stream has relocated southward and the lows, which used to hit central Europe before, are now bound for Spain and the Mediterranean Sea. (A closer look at the precipitation data of Spain, Morocco an Algeria should provide some very interesting results.)
These are huge measured changes in surface forcing compared with the calculated CO2 forcing.
For this paper-
Forcing of +3.9 W/m^2/decade slope
Temp trend = 0.07 C/decade (from GHCN v3 for Spain)
Average full-sun forcing over 25 yr period = 5 W/m^2 during day.
Spain averages about 5 hours of peak solar per day.
Average forcing over 25 year period = 5*5/24 = 1.04 W/m^2
Sensitivity = 0.07 C/W/m^2 for 25 year period
But there have been other papers-
Changes in surface shortwave solar irradiance from 1993 to 2011 at Thessaloniki (Greece)
A.F. Bais*, Th. Drosoglou, C. Meleti, K. Tourpali, N. Kouremeti
International Journal of Climatology, December 7, 2012
They say data from 1990 – 2011 shows a global increase in shortwave downward radiation from the sun of 0.33% per year. Given an average peak sun hours per day of 5, this corresponds to a 24 hour averaged forcing of 0.7 W/m^2 per year. Taken over a period of 19 years, that amounts to a peak forcing of 13.3 W/m^2, or an average forcing of 6.7 W/m^2 over a 19 year period. Global temperatures from 1990 – 2011 have increased by 0.34 C.
This gives a climate sensitivity over a 20 year time frame of 0.05 C/W/m^2.
Variability of the surface radiation budget over the United States from 1996 through 2011 from high-quality measurements, by John A. Augustine, Ellsworth G. Dutton, Journal of Geophysical Research – Atmospheres.
“A significant upward trend in downwelling shortwave [solar radiation](SW-down) of +6.6 Wm−2 per decade dominates the total surface net radiation signal…The dramatic surface net radiation excess should have stimulated surface energy fluxes, but, oddly, the temperature trend is flat.”
The temperature increase from 1996 – 2011 for US is 0.00 C according to NCDC. Over this time, increase is 11.5 W/m^2, or average of 5.7 W/m^2. With 5 hrs/day, this gives 24 hour average of +5.7*5/24 = 1.2 W/m^2.
Sensitivity over 14 year period is 0.0/1.2 = 0.00 C/W/m^2.
And of course, from NREL monthly data on solar insolation averaged at stations over 30 years, along with average monthly temperatures at the same location, the climate sensitivity over the U.S. over a 0.5 year time frame is 0.085 C/W/m^2.
To summarize:
For the U.S., we have a 0.085 C/W/m^2 over 0.5 years.
For the U.S., we have a 0.00 C/W/m^2 over 15 years.
For Spain we have 0.07 C/W/m^2 over 25 years.
Globally we have 0.05 C/W/m^2 over 20 years.
Little confusion. Isn’t “global brightening” an increase in albedo, the opposite of what’s described in the column?
Leif, the CRF/Solar cloud effect is expected to be confined to areas over the ocean. The effect would not be noticable in areas that already have sufficient aerosols for cloud nucleation.
David in Cal says:
“Does the impact of greater cloud cover in the net produce more warming or more coollng?”
I would think that it is a cooling affect since there would be less rays reaching the surface in the first place reducing the amount that reflects back to earth.
Do you have anything more than your conjecture to support this?
Temps aren’t all that warm ‘at altitude’ so the radiative efficiency isn’t going to be ALL that great … [some] satellite images, or sounder imagery/data ought to exist to support this.
.
Here’s the same trend for the UK:
http://www.metoffice.gov.uk/climate/uk/actualmonthly/17/Sunshine/UK.gif
and by looking at the spikes shows it is directly related to the AO/NAO and hence the jet stream position, which is then determining cloud cover.
I think it’s plausible the cloud formation due to CRF could cause a reduction in clouds over land. It would likely reduce total water vapor availible for clouds over land.
Ocean circulation is probably the main factor (which may be related to solar activty and magnetic field) though.
Change: “same satellite images, ”
To: “some satellite images, ”
Doh!
In reply to:
aaron says:
June 7, 2013 at 5:02 am
Little confusion. Isn’t “global brightening” an increase in albedo, the opposite of what’s described in the column?
William:
The term ‘global brightening’ is perhaps confusing. Due to a reduction in planetary cloud cover in the regions in question (not the entire global only in the specific regions, specific regional global brightening would be a more accurate term), there is less sunlight reflected off into space. The additional sunlight that reaches the ground causes the regional warming which the warmists call global warming (the warmists should also if they were concerned about clarity and the cause of the observed warming should have stated specific regional warming).
The warming in the last 20 years was regional warming not global warming.
The logical points noted below (supported by peer reviewed analysis) supports the assertion that the majority of the warming in the last 20 years was caused by a reduction in planetary cloud cover due to solar magnetic cycle changes not an increase in atmospheric CO2.
A consequence of that assertion is the warming in the last 20 years is reversible. As CO2 warming is not reversible, significant cooling would prove that the majority of the warming in the last 20 years was due to changes in planetary cloud cover rather than the increase in atmospheric CO2. This would also explain why there has been a lack of warming for the last 16 years.
The regions of the planet that warmed in last 20 years (high latitude and primarily in the Northern hemisphere) are the same regions where there is ‘global brightening’. The regions of the planet that warmed in the last 20 years are the same regions that have cyclically warmed and cool in the past. It is known from analysis of sea sediment and ice cores that solar magnetic cycle changes correlate with the past cyclic warming and cooling periods. The logical question that should have been asked is the warming in the last 20 years due to the same mechanisms that caused warming in the past?
It is interesting as there has been an abrupt change to the solar magnetic cycle we will have a chance to determine by observation rather than by models, theoretical calculations, and predictions how much of the warming in last 20 years was due to solar modulation of planetary clouds vs increases in atmospheric CO2. There is this year the start of cooling in the same regions that experienced warming in the last 20 years.
http://www.solen.info/solar/images/comparison_recent_cycles.png
Greenland ice temperature, last 11,000 years determined from ice core analysis, Richard Alley’s paper.
http://www.climate4you.com/images/GISP2%20TemperatureSince10700%20BP%20with%20CO2%20from%20EPICA%20DomeC.gif
The AGW theory predicted that the majority of the warming should be in the tropics where there this the most amount of long wave radiation emitted off into space. The warming in the last 20 years is not in the tropics. In addition the AGW theory predicted that due to increased water vapor there should be significant warming in the tropics roughly 8 km above the earth. There is no observed warming in tropics at roughly 8km above the earth. The likely reason for the fact that there is no tropical tropospheric warming is that planetary cloud cover increases or decreases in the tropics to resist any forcing change (this assertions are supported by peer reviewed papers).
http://arxiv.org/ftp/arxiv/papers/0809/0809.0581.pdf
Limits on CO2 Climate Forcing from Recent Temperature Data of Earth
… The effects in the northern extratropics are not consistent with CO2 forcing alone. …
An underlying temperature trend of 0.062±0.010ºK/ decade was estimated from data in the tropical latitude band. Corrections to this trend value from solar and aerosols climate forcings are estimated to be a fraction of this value. The trend expected from CO2climate forcing is 0.070g ºC/decade, where g is the gain due to any feedback. If the underlying trend is due to CO2 then g ~1. Models giving values of greater than 1 would need a negative climate forcing to partially cancel that from CO2. This negative forcing cannot be from aerosols.
These conclusions are contrary to the IPCC [2007] statement: “[M]ost of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.”
http://icecap.us/images/uploads/DOUGLASPAPER.pdf
A comparison of tropical temperature trends with model predictions
We examine tropospheric temperature trends of 67 runs from 22 ‘Climate of the 20th Century’ model simulations and try to reconcile them with the best available updated observations (in the tropics during the satellite era). Model results and observed temperature trends are in disagreement in most of the tropical troposphere, being separated by more than twice the uncertainty of the model mean. In layers near 5 km, the modelled trend is 100 to 300% higher than observed, and, above 8 km, modelled and observed trends have opposite signs. These conclusions contrast strongly with those of recent publications based on essentially the same data.
http://www-eaps.mit.edu/faculty/lindzen/236-Lindzen-Choi-2011.pdf
On the Observational Determination of Climate Sensitivity and Its Implications
Richard S. Lindzen1 and Yong-Sang Choi2
… We again find that the outgoing radiation resulting from SST fluctuations exceeds the zerofeedback response thus implying negative feedback. In contrast to this, the calculated TOA outgoing radiation fluxes from 11 atmospheric models forced by the observed SST are less than the zerofeedback response, consistent with the positive feedbacks that characterize these models. …. … However, warming from a doubling of CO2 would only be about 1C (based on simple calculations where the radiation altitude and the Planck temperature depend on wavelength in accordance with the attenuation coefficients of well mixed CO2 molecules; a doubling of any concentration in ppmv produces the same warming because of the logarithmic dependence of CO2’s absorption on the amount of CO2) (IPCC, 2007). This modest warming is much less than current climate models suggest for a doubling of CO2. Models predict warming of from 1.5C to 5C and even more for a doubling of CO2. Model predictions depend on the ‘feedback’ within models from the more important greenhouse substances, water vapor and clouds. Within all current climate models, water vapor increases with increasing temperature so as to further inhibit infrared cooling.
lsvalgaard says:
June 6, 2013 at 5:32 pm
This increase is linked to the decreased presence of clouds
So fewer and fewer clouds along with a less active sun…
Are you suggesting that during weak solar cycles/ less solar activity, the sun produces less cloud cover as it is unable to drive enough moister into the air that will form clouds which in-turn will keep the geographic area that the clouds form over warm a night?
Would this process also cause an increase in fog during autumn, winter and spring?
William Astley says:
June 7, 2013 at 8:49 am
The warming in the last 20 years was regional warming not global warming.
From http://journals.ametsoc.org/doi/pdf/10.1175/BAMS-D-11-00074.1 :
“Available satellite-derived products qualitatively agree on a brightening from the mid-1980s to 2000 globally”
The logical points noted below (supported by peer reviewed analysis) supports the assertion that the majority of the warming in the last 20 years was caused by a reduction in planetary cloud cover due to solar magnetic cycle changes
There is no support for such an assertion. Many people claim just the opposite: lower solar activity = more cosmic rays = more clouds. Most likely, both of these contradictory claims are wrong.
Sparks says:
June 7, 2013 at 8:56 am
“This increase is linked to the decreased presence of clouds”
‘So fewer and fewer clouds along with a less active sun…’
Are you suggesting that during weak solar cycles/ less solar activity, the sun produces less cloud cover
I’m pointing out that observations show that during the decreasing solar activity, there was also decreasing cloud cover. Whether these things are related is another matter, but any claim that they are must account for the above empirical fact.
Let’s eliminate confusion as to correlations between solar brightening, on the one hand, and reduced airborne pollutants, on the other, in several different parts of the world. I use the term “several parts of the world” because places like southern Asia have been increasing such pollutants, as the US and OECD Europe and Russia have been decreasing them. See:
“Anthropogenic and natural contributions to regional trends in aerosol optical depth, 1980–2006,” Streets et al., JGR, 2009.”
Look at Figs 5 and 6 specifically.
Bottom line: solar brightening in different parts of the world is well correlated with reduced airborne pollution, whether the trends of pollution is up (south Asia, where solar dimming has been occurring), or the US and OECD Europe (poluttion slowly dropping since early 1980s, starting data point in study) and Russia (pollution dropped most dramically in early 1990s, when FSU dissolved.
A weaker sun has only been in the last 6 or so years, hasn’t it?