Arguments
Solar activity & climate: is the sun causing global warming?
The skeptic argument...
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)
What the science says...
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In the last 35 years of global warming, sun and climate have been going in opposite directions |
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Over the last 35 years the sun has shown a slight cooling trend. However global temperatures have been increasing. Since the sun and climate are going in opposite directions scientists conclude the sun cannot be the cause of recent global warming.
The only way to blame the sun for the current rise in temperatures is by cherry picking the data. This is done by showing only past periods when sun and climate move together and ignoring the last few decades when the two are moving in opposite direction.
Figure 1: Global temperature (red, NASA GISS) and Total solar irradiance (blue, 1880 to 1978 from Solanki, 1979 to 2009 from PMOD).
Last updated on 19 March 2013 by Stephen Leahy. View Archives
To understand the link between solar insolation and global climate, one must first understand what sunspots represent, and why they track so well with mean atmospheric temperatures.
Sunspots appear when the sun's magnetic field begins to flip, as it does for some unknown reason every nine to thirteen years (the famous 11-year solar cycle). The sunspots are regions of magnetic disturbances (irregularities) which correlate with distortions in the sun's corona, with solar flares and with coronal mass ejections.
The lay person could view sunspots like holes in a giant cosmic sprinkler system -- each spot spews enormous amounts of energy out into the solar system. The law of conservation of mass and energy require the entire solar system to either heat or cool, depending on the number and duration of sunspots, and the total solar equivalent energy output. However, the exact energy variability is not yet quantified. Data from satellites like SOHO and STEREO and ULYSSES are still under analysis, and won't yield science applicable to climate change for at least another 10 years.
In the meantime, ice core data has already indicated temperatures over the past 600,000 years have increased (on average) about 800 years before CO2 started to increase. It is hard to argue any CO2 increase caused global warming to occur some 800 years BEFORE it began.
Most of the world’s CO2 is actually not in the atmosphere, it is dissolved in the oceans. When global temperatures increase, the oceans give up some of their CO2, outgassing it into the atmosphere and increasing atmospheric concentrations. The amount of CO2 thus "outgassed" is far greater than the total CO2 produced by all anthropogenic sources combined. Mean atmospheric CO2 concentration would seem to be a good proxy for mean global ocean temperature.
Most climate scientists today agree that some external force (the sun, changes in the Earth’s tilt and rotation, etc) caused past global temperature increases, which were then followed by increases in atmospheric CO2.
Declaring the change in CO2 (0.01%) significant, while ignoring the change in solar insolation (0.1%) as insignificant is equivalent to scientific malfeasance.
please point me to any scientific paper claiming that the forcing leading to the glacial-interglacial cycles has been CO2. It's astonishing how this trivial mistake keeps hanging around.
Odd. The quote you cite appears to be from Lockwood 2010, which just came out. Google only has two references to that quote, one from the 2010 paper itself and one from a very recent commentary about it.
I don't doubt you, but could you tell us which of the links at the top of the thread has that quote?
Why does CO2 lag temperature?
The significance of the CO2 lag
You can find more by typing the word "lag" into the Search box at the upper left.
Likewise, we are all very familiar with the fact that "Most of the world’s CO2 is actually not in the atmosphere, it is dissolved in the oceans." This is the source of part of the CO2/temperature feedback, which amplified the Pleistocene glacial/interglacial cycles. However, it's quite clear that the oceans are currently a sink rather than a source for atmospheric CO2. See here
Is the long-term trend in CO2 caused by warming of the oceans?
CO2 is [not] coming from the oceans
See also Takahashi 2009 and Sabine 2004.
Finally, you end with the following comment: Declaring the change in CO2 (0.01%) significant, while ignoring the change in solar insolation (0.1%) as insignificant is equivalent to scientific malfeasance.
With all due respect, you have that seriously confused. CO2 is increasing by about 1% per year, and will double before the end of this century.
If you're referring to the absolute concentration of CO2 in the atmosphere, that's completely irrelevant. I'm not sure what source led you to think that is significant ... but you should probably discount anything else that source is telling you, because it's just plain wrong.
That's true of some past climate changes, but not others. See the discussion in this thread. There have been quite a few times when changes in climate were driven by changes in CO2.
You might also be interested in Richard Alley's AGU presentation CO2: The Biggest Control Knob: Carbon Dioxide in Earth's Climate History
I am not a scientist, just into financial analysis and statistics with a strong intrest into how the sceptical science progress works with regard to AGW.
I would like to challenge you with the following hypothesis with regard to the amplitude of solar forcing in the current climate system.
Estimations of climate sensitivity based on top-of-atmosphere
radiation imbalance, (Atmos. Chem. Phys., 10, 1923–1930, 2010
www.atmos-chem-phys.net/10/1923/2010/
© Author(s) 2010) is the most recent study that I believe will solve much of the problem about the portion of solar forcing as stored in the present climate memory (soil, cryosphere, oceans, etc.).
From the abstract:
In this study, the TOA imbalance value of 0.85 W/m2 is used. Note that this imbalance value has large uncertainties. Based on this value, a positive climate feedback with a feedback coefficient ranging from −1.3 to −1.0 W/m2/K is found. The range of feedback coefficient is determined by climate system memory. The longer the memory, the stronger the positive feedback. The estimated time constant of the climate is large (70120 years) mainly owing to the deep ocean heat
transport, implying that the system may be not in an equilibrium state under the external forcing during the industrial era. For the doubled-CO2 climate (or 3.7W/m2 forcing), the estimated global warming would be 3.1K if the current estimate Correspondence to: B. Lin
(bing.lin@nasa.gov)
of 0.85 W/m2 TOA net radiative heating could be confirmed. With accurate long-term measurements of TOA radiation, the analysis method suggested by this study provides a great potential in the estimations of middle-range climate sensitivity.
From the results:
Coupled ocean-atmosphere GCM simulations (Hansen et al., 2007) show that the climate response for an instantaneous 2×CO2 forcing reaches 60% of the equilibrium response after 100 years and 90% after 1000 years. The former system response corresponds to a time constant of 109 years, which is consistent with current estimates, while the latter indicates another even bigger time constant of the climate system of about 434 years. This longer time scale may be related to thermohaline circulations of the deep ocean, whose physical processes are beyond the scope of current study.
It has been discussed that the mainly short-wave radiation originating from direct solar radiation heats the ocean more efficiently than long term radiation from the atmosphere. I don't want to enter into a debagte about that again. So let's assume, the memory for both solar and greenhouse forcing is about the same over time.
Solar forcing at the beginning of the industrial area was about 1365.3 W/m2, it then increased steadily to reach about 1366.2 W/m2 in 1960. The 2000 forcing is about 1365.8, which makes it an average forcing of about 1366 W/m2 during those 40 years. This means a sustained natural forcing of about 0.7W/m2 above year 1880 affected the climate system between approx. 1950 - 2005. Therefore, even though we are now in a sustained solar minimum, the memory of the climate system resulting from about +0.7W/m2 solar irradiance is now 60 years old. If, according to AOGCMs, only 60% of the equilibrum response is reached after 100 years for CO2 doubling, I deduce at least the same (if not longer periods) are required for an equilibrium response to solar forcing. Assuming, it is the same, it is safe to assume that at least 40% of the current, estimated radiative imbalance of 0.85W/m2 since 1880 is due to solar forcing. Why? 0.28W response is given after 100 years and later, this leaves a minimum of 0.35W in the memory after 60 years, in 2010. This leaves 0.5W/m2 owing to human forcings, not 0.85W/m2 as "committed" atmospheric warming resulting from human activities for the future. Since, with its logarithmic effect, we reached roughly 1.6W/m2 forcing since the beginning of ia. Subtractingg 0.5W/m2, this leaves 1.1W/m2 to increase temperature of the atmosphere. So with model average beeing S=3°C for 2xCO2eq (3.7W/m2), temperature increase owing to human radiative forces should be roughly +0.9°C from surface to TOA. Even IF this is the case and can be measured soon, it will take 1000 years to reach 90% of the 3°C increase for 2xCO2, remember?
Solar forcing at the beginning of the industrial area was about 1365.3 W/m2, it then increased steadily to reach about 1366.2 W/m2 in 1960. The 2000 forcing is about 1365.8, which makes it an average forcing of about 1366 W/m2 during those 40 years.
The average solar forcing reaching the earth at any particular time and weather and place is 240 W/m2 according to http://data.giss.nasa.gov/gistemp/2007/ .
I divide the figures used in comment "*558 by 5.8.
Therefore, even though we are now in a sustained solar minimum, the memory of the climate system resulting from about +0.12W/m2 solar irradiance is now 60 years old. If, according to AOGCMs, only 60% of the equilibrum response is reached after 100 years for CO2 doubling, I deduce at least the same (if not longer periods) are required for an equilibrium response to solar forcing. Assuming, it is the same, it is safe to assume that at least ...% of the current, estimated radiative imbalance of 0.85W/m2 since 1880 is due to solar forcing. Why? 0.05W response is given after 100 years and later, this leaves a minimum of 0.06W in the memory after 60 years, in 2010. This leaves 0.79 W/m2 owing to human forcings, not 0.85W/m2, as "committed" atmospheric warming resulting from human activities for the future. Since, with its logarithmic effect, we reached roughly 1.6 W/m2 forcing since the beginning of ia. Subtracting 0.79 W/m2, this leaves 0.81 W/m2 to increase temperature of the atmosphere. So with model average beeing S=3°C for 2xCO2eq (3.7W/m2), temperature increase owing to human radiative forces should be roughly +0.65°C from surface to TOA.
We have barely begun to quantify the interaction between the solar wind and the magnetosphere, which transfers highly variable amounts of energy to the earth's climate system. While early estimates indicated this energy exchange was negligible in comparison to TSI (only a few watts per square meter), it is NOT negligible compared to the assumed forcing of anthropogenic CO2 in earth's atmosphere (also a few watts per square meter).
Until these phenomena have been successfully observed, measured and monitored for several decades, it will be impossible to adequately account for CO2 forcing.
If you're trying to say - and until then we should do nothing based on on our current limited understanding - then you're failing to understand science generally.
In the medical sciences, prescriptions and procedures are tried out, and adjusted when necessary. In the social sciences, economics models and projections are commonly used despite no-one understanding if or when any projection will ever be reliable.
Life isn't mathematics. Science isn't mathematics. You want absolute certainty? Stick with maths, avoid science.
Read:
"Quantitative modeling of magnetospheric processes" (Olson, W.P. - American Geophysical Union, 1979)
This book contains the paper by Paulikas & Blake:
"Effects of the Solar Wind on Magnetospheric Dynamics: Energetic Electrons at the Synchronous Orbit" (Paulikas, G.A. and Blake, J.B. - pp. 180-202)
Also, read:
"Solar Wind Magnetosphere Coupling" (Kamide, Y. and Slavins, J.A.; Terra Scientific Pub. Co., 1986)
Pharmaceutical companies do not invest trillions of dollars to "try out" a new medicine to "see if it works". Surely you aren't proposing we bankrupt the world's economy and limit future industrial development over an irrational fear? Surely you want action based on proper scientific study and evaluation?
And while (not "medical sciences") pharmaceutical companies do invest billions of dollars for truly promising cures, they are using their own profits, not my hard-earned income, taken by the government through taxation.
If you aren't following, then consider the following polemic arguments (as unscientific as AGW):
AGW proponents seem intent on taking my money to fight global climate change. Nonsense! Stop studying pseudo-science and go get a real job, so I won't have to support you anymore. This applies to Dr. James Hansen as much as anyone. His grasp of climate science is limited to his computer model, which has been unfairly compared with direct observations at the top of this subject string.
Solar, Wind, and other renewable energy sources will become competitive as fossil fuels run out, and prices for fossil fuels naturally rise. When this happens, atmospheric CO2 levels will necessarily begin to fall.
The only question is how high will CO2 levels rise before fossil fuels run out? Based on the reading I've done, this seems to be somewhere between 2X and 5X current levels (that's 1500ppm, or 0.15% CO2).
Just so we're clear, all of the AGW fear-mongering to date has been over 0.008% of the earth's atmosphere (+80ppm of CO2). Until the OCO is launched and collects its data, we don't have any reliable method of estimating changes as small as 0.008% of anything global.
Again, based on the papers I've read, this would generate mean global temperature increase of no more than 10 degC. The increase would occur slowly, over the course of the next 1000 years. Therefore, predictions of coastal flooding and massive loss of life due to climate change (which happens over a period of decades) are simply sensational and unscientific. There remains a complete lack of any objective scientific data to demonstrate that hurricanes, typhoons, floods, or droughts have increased in either number or severity over the course of the last century.
However, a 10-degree mean temperature increase coupled with 3-fold CO2 increase would produce ideal growing conditions. Plants would thrive. We'd be faced with battling all weeds the way some battle bamboo or briar patches in rich soil. Since the food chain relies on a strong foundation of plant life, all animals would thrive as well.
In addition, higher global temperatures could result in preventing or delaying the onset of the next Ice Age -- a highly desirable result. Land animals cannot survive an ice ball planet, and crops will fail if growing seasons are cut short.
The question is not whether ocean levels will rise, or more flooding and droughts will occur if temperatures are generally higher over the next few centuries; the question is how are we preparing for the coming Ice Age?
Do we bankrupt our economy chasing after a little hot air, or do we begin investing in technologies to help us survive a dormant Sun?
Since even a 6 degree rise would be disastrous, I think you'll have a very hard time finding anyone to sell those crops to. ;)
Try these, for starters :
Models are unreliable
We're heading into an ice age
It's not bad
CO2 measurements are suspect
Hanson's 1998 prediction was wrong
Animals and plants can adapt to Global Warming
The rest of the arguments are here
Johno, it's generally better to stick with one or two topics in a given comment, rather than tossing in economics, taxation, climate models, climate sensitivity, the fact that CO2 is a small fraction of the mass of the atmosphere, reliability of CO2 measurements, climate change impacts, the CO2/primary productivity relationship, ice ages, and solar irradiance.
Throwing everything at the wall to see what sticks doesn't lead to very productive discussions.
"It isn't happening and it's good for us" is not very persuasive, leaving aside your contrarian liturgy of wrongness. It leaves me wondering why you're so passionate about proving the case for AGW wrong if you're so keen on it happening.
You also might take a look at the Stern Review w/regard to costs and benefits of mitigation. Though criticized in a way remindful of critiques of climate change science, it still has the virtue of existence, something its critics have not been able to address with their own implementation.
An old story but useful. If somebody ends up talking about their money they're not really interested in science and wasting further time in discussion is probably pointless.
As for the fear of an impending ice age, so long as you don't see a huge ice sheet creeping down over Canada, you can rest assured.
The polar ice caps had melted in many of those warmer periods, which means that the oceans were several tens of meters higher than they are now. Of course that wouldn't be a problem would it? ;o)
The point is that our agriculture and civilisation has adatped to suit a particular climate. If the climate changes then we have to adapt our agricultre, which can only be done at a cost; a cost that a large proportion of the Earth's population cannot afford (as they are already at subsitence level or worse). Even if overall productivity goes up, that doesn't mean that it will go up everywhere, so what happens to the countries that find because of first world use of fossil fuels their country can no longer support its population? That wouldn't be a bad scenario perhaps for someone who wanted a world government that oversaw the redistribution of wealth to make sure everyone got enough of that food to live on, but I don't think that would be everybodys cup of tea!
In short, the change is a problem, regardless of the eventual destination. There is also a risk the destination will be bad in its own right, but it doesn't have to be for climate change to be a problem worth trying to avoid.
I am still working towards my geophysics degree so I apologize for the continued questions. In a period with a "much cooler" sun, other than increased volcanic activity, what would be another source that could contribute global increases in CO2 to the point of global warming?I could see ice melting releasing methane and CO2, but wouldn't solar influence be the cause for this to happen? If so, would the origin of of all global warming or cooling be the sun? I understand the complexity of climate changes, but I'm trying to simplify the process to find the origin.
If I understand you correctly, you're asking what could be causing the rise in CO2 levels other than human activity? We actually have many lines of evidence that clearly point to the burning of fossil fuels causing rising CO2. Firstly, the simple numbers that we're emitting around 28 billion tonnes of CO2 per year while the actual amount of CO2 in the air is going up by around 15 billion tonnes per year. Secondly, the type of carbon in the air matches the type of carbon that comes from fossil fuels - a distinct human fingerprint. Thirdly, we see the same pattern in carbon isotopes in corals - another fossil fuel fingerprint. So there is really only one explanation for the sharp rise in CO2 and it's the common sense explanation - much of the CO2 we're throwing into the air is staying there.
I believe the answer is a "DaisyWorld" scenario, described in the CO2 was higher in the past thread - with a lower solar output, glaciers cover the world, and block weathering absorption of CO2 by rocks. Over geologic time, CO2 from continuing volcanos accumulate, until enough ice melts to allow weathering to catch up again. It's a slow feedback cycle.
I could be wrong, though; I'm certainly not a geologist - I invite corrections if I'm just making things up here :)
Sorry, I should have stated more clearly I was inquiring about past warming cycles with higher CO2 concentrations (with a cooler sun). I think KR posted above providing a potential cause for rising CO2 levels which cause warming with a much cooler sun compared to present. If I understood your first response correctly, previous warming was caused by increased CO2 levels caused by non-solar forces. I'm trying to understand what causes CO2 levels to rise high enough to cause warming (excluding fossil fuels, volcanic activity, and the sun). This also begs the question: if current global warming is caused by solar forces AND CO2, are we not fast-tracking the earth to provide a natural balance as seen in the past (assuming an origin for increased CO2 is the sun).
Temperatures are related to both CO2 and solar input, as described on CO2 was higher in the past.
The difficulty now is that we're adding CO2 at an extremely high rate by geologic standards, and the geological weathering feedback and other CO2 sinks are too slow to keep up. We're entering a new domain, as described on On temperature and CO2 in the past. I'm not looking forward to the temperature catching up with current CO2 and solar levels...
In my opinion, we can't come to any realistic conclusion when too many variables such as solar influence are not fully understood. This leads a person with an open mind like me to wonder why such drastic measures are being proposed when the situation is still not factually conclusive.
I'm a firm believer that we're not going to go extinct any more than are cockroaches, but by ignoring what we're doing we're going to end up living a little bit more like cockroaches. Why would we want to do that? Folks raising their hands "aye" to enjoying our present living standard should pay heed. Just ask President Medvedev of Russia. He's got a fresh perspective on "adaptation."
Volcanoes emit at a time averaged ~1% of current human rates - they aren't similar.
As to solar influence - that's really pretty well understood. It's been decreasing since the 1970's, but over geologic/cosmic time it's been brightening, as per its life cycle. Stellar evolution is considered to be very well understood - we've got, after all, billions of examples to look at.
There's a nice image of the solar life-cycle on Wikipedia.
Apologies for spamming the forums! heres one source that discusses the low earth orbit/atmospheric friction/ solar activity
No harm in being a layman in anything. All of us were at one time.
Remember the atmosphere is layered, like an onion. Forces that act on one layer may, or may not, act upon an adjacent one. Increasing CO2 exerts its main influence in the upper troposphere, the lowest layer, causing it to warm. Lack of energy being transmitted upward from the troposphere to the stratosphere means the stratosphere cools (which is measured by satellites).
When layers cool, they can compress, thinning somewhat. Recent UV output from the sun has been declining, causing the thermosphere, one of the outer layers of the Earth's atmosphere, to compress downward, to a record low thickness. The net effect of this compression is less atmospheric drag on our communication & research satellites in low Earth orbit (which extends their service lifetime - bonus!).
Note that changing energy levels of the various layers of the atmosphere or their thicknesses has no effect on the mass of the column of air above any point on the Earth (which is what determines the local air pressure).
Atmospheric physics is a complex area of study. Even experts in it get confused sometimes (or tripped by the D-K Effect). For an introductory starting point, try start here first, then go here, then go here to figure out where to go next.
Wiki, surprisingly, is a good source as well. Once you know what to type in, anyway (Catch-22: you have to know enough to search for what to learn about next, but how do you search if you're a complete beginner?).
Hope this helps,
The Yooper
Anyhow, looks like i have a few years worth of reading, experimenting and computer modelling to go lol... All I can say is Im half between 'Tax on Co2' being a government attempt to charge more for less resources (charge more for fuel and electricity whilst not having to invest in infrastructure for the ever growing global population,peak oil etc, after all Climategate has done the scientific community no favours at all either way) and a very serious genuine problem that needs to be addressed urgently yet is being cashed in on by unscupulous politicians and glory seeking scare mongerers!..anyhow, thanks for the excellent reply and will get thinking, researching and trying to test some ideas out!
Have we ? Having seen this year so far break most global temperature records, it would be interesting to see how you came up with that particular statement. Where did you get it from ? Or is it something you worked out yourself ? If so, what information did you use ?
Here are some other threads on this site, to do with other matters you have included in your post :
Mars is not warming globally
Land use
CO2 coming from the ocean
CO2 is the main driver of climate change
It's the sun
Climategate 'conspiracy'
Thanks again
Instrumental temperature record
Why not look further from there, or from another thread on this site :
Are surface temperature records reliable?
There are three versions to look at in the above, depending on how much detail you are looking for.
You still haven't said where you got your information concerning the "mild period of cooling over the last couple of years". Can you reveal all, to me or Jim...
Start Here
There is also plenty of information (and many sources) here :
IPCC Summary for Policymakers
Why aren't you more forthcoming as to the sources of your information ? Provide a few examples of where contrary information is being given that you believe is as believable as any of the information you find on this site.
http://www.canadafreepress.com/2004/deweese121404.htm
http://www.telegraph.co.uk/earth/environment/climatechange/7369339/New-evidence-for-man-made-global-warming.html
http://uk.answers.yahoo.com/question/index?qid=20091123115037AAItLGF
they are not scientific sources although they do cite them selves as such, however given the massive number of variables at play in the overal arena of 'warming' or 'cooling' whos to say they are any more accurate than anyone elses opinions? im sure next week will be another startling media discovery or discreditation to do with climate anomolies... from where Im sitting with the information presented to me via these forums, the internet as a whole not to mention having lived in many locations around the globe and witnessed first hand from real people discussing the way in which their environments have changed, eg lack of snow on peaks, reservoir depletion and also the opposite too, snow storms, floods etc all of which where loclalised events but none the less at each place I have been to every one seemed to agree that one way or another something is changing percevably with the climate. anyhow, I could fire up a supercomputer and feed lots of stats in and see what the results tell me, but even so, if I miss so much as one variable or miscalculate or use inaccurate results im going to be back at square one with 'im not sure'... however theres a good chance its this...
If you discount stats and research (ie, science), you're pretty much left with anecdotal data. Why, in this day and age, anyone would think that anecdotal data has any real standing in science amazes me. Looking for science information in the media also seems suspect to me. I'm not a climatologist, but I am a scientist, and the number of times that the media has gotten things wrong in areas I do know about are depressing.
From your links :
The BBC one is a blog post from a year ago;
The Canada Free Post one is an Opinion piece from 6 years ago;
The Telegraph article (by an Environmental reporter) is about a report, published in Wiley Interdisciplinary Reviews Climate Change, which confirms what you could find by sticking to the actual science;
The Yahoo Answers link is not worth the paper it's not printed on !
Don't rely on blogs, opinion or the mass media. Try the links I gave above, plus :
Scientific American
The Discovery of Global Warming
Science
Science News
Science Daily
Physics World
New Scientist
Nature
National Academies, and here
Knight Science Journalism Tracker
Climate Central
Climate Data
What affecting climate... well without moving the earth's plates around you have four ways to influence climate.
1 solar - amount and distribution. Stable or dropping
2 aerosol - stable
3 albedo - actually replacing forest by agriculture increases albedo and so a net cooling affect.
4 GHG - increasing and unsurprisingly, so is temperature.
http://www.metoffice.gov.uk/climatechange/
However I cant help but feel that a very real problem is being used as an excuse to keep energy company shareholders happy - charge more for less - after all... its saving the world lol