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Author Topic: Climate Change: Driven by Humans or Natural Cycles? An Answer.  (Read 4116 times)

Offline Snowlover

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Hello, folks. This is my first time visitng this forum, and I shall provide an answer to the very debated question: Has Climate Change mainly been driven by humans or by a natural cycle? I shall present evidence that Climate Change has been driven by natural cycles, and that the CO2 Forcing is very small and insignificant, and can be overcome by simple albedo changes alone.

 


 

Offline Snowlover

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There is so much evidence that Clouds have completely overwhelmed the CO2 effect in the past, and are currently doing so. Let's start off with the basics, which is to figure out what is the dominant driver of the Climate System. Is it Anthropogenic CO2 or is it a natural cycle? To begin to determine this, we have to look at the equator for the monthly OLR that is escaping Earth's atmosphere. This is where we can look at OLR changes with the most accuracy, since the Tropics do not experience as much seasonal variation or albedo change as the NH or SH do, so to get rid of all of this noise that might influence the average OLR at the TOA we look at the Tropics.



The Climate Models have predicted a "hot spot" for CO2 doubling to appear by the Tropics. This is because of the hypothesized positive water vapour and cloud feedback at the Tropics. However, none of this has been observed at all. In fact, we observe an increase in OLR at the Tropics, which could validate newbielink:http://eaps.mit.edu/faculty/lindzen/adinfriris.pdf [nonactive]" It bascially states that as the planet warms, Cirrus clouds will decrease, which would allow for more OLR to reach the TOA, and produce a negative feedback on Earth's Climate. Two new peer reviewed papers document strong negative feedback from Cloud Cover. ( newbielink:http://iopscience.iop.org/1748-9326/6/3/034032 [nonactive]) ( newbielink:http://www.usclivar.org/Newsletter/VariationsV4N1/BrethertonCPT.pdf [nonactive])

Quoting respectably from the papers:

Quote
We find that globally adding a uniform 1  W m − 2 source of latent heat flux along with a uniform 1  W m − 2 sink of sensible heat leads to a decrease in global mean surface air temperature of 0.54 ± 0.04 K. This occurs largely as a consequence of planetary albedo increases associated with an increase in low elevation cloudiness caused by increased evaporation. Thus, our model results indicate that, on average, when latent heating replaces sensible heating, global, and not merely local, surface temperatures decrease.

Quote
The CAM-SP shows strongly negative net cloud feedback in both the tropics and in the extratropics, resulting in a global climate sensitivity of only 0.41 K/(W m-2), at the low end of traditional AGCMs (e.g. Cess et al. 1996), but in accord with an analysis of 30- day SST/SST+2K climatologies from a global aquaplanet CRM run on the Earth Simulator (Miura et al. 2005). The conventional AGCMs differ greatly from each other but all have less negative net cloud forcings and correspondingly larger climate sensitivities than the
superparameterization. The coarse horizontal and vertical resolution of CAM3-SP means that it highly under-resolves the  turbulent circulations that produce boundary layer clouds. Thus, one should interpret its predictions with caution. With this caveat, cloud feedbacks are arguably more naturally simulated by superparameterization than in conventional AGCMs [conventional climate models], suggesting a compelling need to better understand the differences between the results from these two approaches.
 

Offline Snowlover

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The OLR has increased roughly 4.5 w/m^2 per decade on average, since 1979. ( newbielink:http://www.cpc.ncep.noaa.gov/data/indices/olr [nonactive]) This equates to roughly a 11-13 w/m^2 increase in OLR over this timeframe. It also indicates that something else other than CO2 is adding Energy to Earth's Energy Budget, since this roughly 10X CO2's RF since 1790.

The increase in OLR at the Tropics indicates that Cloud Cover may be  most of the reason that OLR has increased by the Tropics, since when Clouds are subtracted from the Global Energy Flows, you get more Incoming Shortwave Radiation that reaches Earth's surface, thus warming Earth, and producing a continued increase in OLR. You get increasing OLR from two sources: decreasing Cloud Cover, since Clouds trap OLR and increasing ISR, which continually increases OLR.

Indeed, multiple sources have confirmed that albedo has decreased since the beginning of measuring the albedo, with one being the ISSCP, and the second being Earthshine.



ISSCP has confirmed that Cloud Cover has decreased by roughly 4-5% from 1983-2000, which when Global Warming was occuring. Since then, Cloud Cover has flatlined, and Global Temperatures have followed suit, instead of increasing, like they should have if CO2 was the dominant driver of the Climate.



The Earthshine experiment calculates albedo through reflected incoming shortwave radiation from albedo changes, that reflects off of the moon. More information on the Earthshine experiment can be found here: ( newbielink:http://www.bbso.njit.edu/Research/EarthShine/ [nonactive])

Through Dr. Phillip Goode and Dr. Enric Palle's calculations, they found that the albedo reconstruction is in very good agreement with ISSCP- that it has decreased substantially and has added several w/m^2 of energy to Earth's Energy Budget.



The blue and black lines are albedo reconstructions, and the red line is the amount of Energy GHGs have added to Earth's Energy Budget since 1790. They are dwarfed entirely by just albedo changes alone. Albedo added 7-8 w/m^2 of Energy to Earth's Energy Budget up until 1790, which probably explains about all of the warming that took place during that time frame.

In their peer reviewed paper, the two solar scientists highlight that cloud variability is likely to account for Global Warming that occured during the late 20th Century. ( newbielink:http://www.iac.es/galeria/epalle/reprints/Goode_Palle_JASTP_2007.pdf [nonactive])

For a lay approach, Dr. Palle has put the Earthshine findings into newbielink:http://lasp.colorado.edu/sdo/meetings/session_1_2_3/presentations/session3/3_06_Palle.pdf [nonactive].



 

Offline Snowlover

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Clouds act as a forcing and as a feedback. So how do we know that most of the decrease in Cloud Cover is simply not a product of warming temperatures, resulting in a positive feedback from increased Carbon Dioxide?

We know that most of the increase in temperature from clouds has not been a positive feedback, because water vapour has not increased at all. With a warmer Earth, the theory is that there will be less water vapour molecules that will be able to condense into Clouds because the planet heats up. You would find a surplus of moisture in the air, if this were to be the case. But you don't.



The graph above is from the NASA Water Vapor Project (NVAP) and shows that over the course of the years, there has been a negative water vapour anomaly that has begun to show up in recent years- meaning that water vapour is decreasing, and that the water cycle is slowing down, contrary to the positive feedback hypothesis, where the water cycle should speed up.

But what could be impacting Clouds if the decrease in Cloud Cover is not due to a positive feedback from warming?

Galactic Cosmic Rays are likely causing the decrease in Cloud Cover, and there is so much evidence that points to Cosmic Rays as being the primary driver of cloud cover changes.

Just this year, the CERN experiment newbielink:http://www.nature.com/nature/journal/v476/n7361/full/nature10343.html [nonactive]



The graph above from Kirkby et. al 2011, show that as more and more Cosmic Rays impact the air, more and more aerosoles are produced, which are the seedlings to cloud formations. When a water vapour molecule condenses on an aerosol, you get a cloud. More of these aerosoles would mean that more clouds would form, and thus, more GCRs have a cooling influence on Earth.

But the most damning piece of evidence that Cosmic Rays are the primary drivers of Cloud Cover are from the FD evidence.

Forbush Decreases occur when high amounts of Coronal Mass Ejections cause there to be sudden subtantially less amounts of GCRs than normal. If GCRs are the primary drivers of Climate Change, you would expect a 5-10 day lag with the amount of aerosoles in the atmosphere after a Forbush decrease. And this is what observational evidence is saying.



The dashed line from newbielink:http://wattsupwiththat.files.wordpress.com/2009/08/svensmark-forebush.pdf [nonactive]is the GCR count and the solid blue line is the aerosol number. A short lag in Global aersoles can clearly be seen right after a Forbush Decrease, which indicates a significant CR-Influence on climate, if Forbush Decreases can have that much of an impact on aerosoles.

In addition, we have newbielink:http://www.astrophys-space-sci-trans.net/7/315/2011/astra-7-315-2011.pdf [nonactive], which is the straw that broke the camel's back in terms of evidence that supports a CR-Influence on Climate.

From the conclusions:

Quote
The superposed epoch analysis confirmed the statistically
significant influence of CR intensity decrease on the state of
the atmosphere. The effect is visible only if FDs exceeding
the threshold (7% amplitude with the Mt. Washington data)
are considered. The result strongly supports the idea that
cosmic rays influence the atmospheric processes and climate.



The group of physicists found that daytime temperatures are increasing faster than daytime temperatures with Forbush decreases, which strongly supports the CR driving Cloud Cover driving Climate Theory. This is because clouds reflect ISR in the daytime, cooling off daytime temperatures, and trap LWR at night. With decreases in Cloud Cover, you would get daytime temperatures warming faster than nighttime temperatures, which would get you a larger diurnal temperature change, and this is what has been observed.

There is even more evidence than this for example, that climate sensitivity is low, but I just gave you a taste of all of the evidence that is out there that supports that about all of the climate change that occured in the late 20th Century- the timeframe where CAGW scientists say that this is where natural cycles can no longer explain Global Warming.
 

Offline JP

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Hi Snowlover,

You might get a better response if you asked a simple question for discussion, rather than posting a multi-page essay.  I'm going to leave this thread up here in case it generates good discussion, but please bear in mind that the usual location for essays that present a non-mainstream view of some topic is the New Theories section of the forum. 

-JP moderator
« Last Edit: 29/09/2011 04:12:21 by JP »
 

Offline Snowlover

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Hi JP,

Thank you for directing me to that part of the forum. I shall post it there instead.
 

Offline Snowlover

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Offline yor_on

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Debate over what JP?

That we don't know yet what the influence of cloud covers have? They seem very complex to me. And using a hypothesis from 2004 to speculate about it? There are so many things put together here that it makes it a headache to discuss. I don't know whether it is a serious try for a refute or if it is a clever disputation for the sake of, whom?

Maybe we should start with Lindzen, Hou, and Chou's hypothesis.

= Quote_

Now, on to the issue of Lindzen’s Iris effect. My wonderful employer, NASA, has a set of web pages which do an excellent job of framing the debate on this topic. Here are the links:

http://earthobservatory.nasa.gov/Study/Iris/
http://earthobservatory.nasa.gov/Study/Iris/iris2.html
http://earthobservatory.nasa.gov/Study/Iris/iris3.html

Please read them all. The issue of who is right is pretty much entirely unresolved at this point, simply because the interaction between surface processes which force Cumulonimbus clouds and the cloud droplet microphysical processes which drive the internal processes within the clouds themselves are exceedingly complex.

I do not know Richard Lindzen. But his two co-authors, Ming-Dah Chou and Arthur Hou are/were in my laboratory. Arthur Hou works three floors below me in the same wing (the “C” wing) of the large Earth Sciences building (affectionately known as “building 33″) at NASA Goddard Space Flight Center. Ming-Dah and I have had many conversations on atmospheric radiation processes. His wife, Sue (Shu-Hsien) shared an office with me for most of the 1990′s. Ming-Dah and Sue retired from U.S. govt. civil service and moved back to their native Taiwan last year. I have the highest respect for Ming-Dah, whose work in parameterizing radiation processes for Global Climate Models is widely used in climate models.

Nevertheless, after having read the original paper by Lindzen, Chou and Hou, I found myself rather skeptical. First of all (and this is just a matter of process, really), the paper was published in the Bulletin of the American Meteorological Society (AMS) — which does not have the same rigorous peer review standards as the more main-stream AMS science journals have. Why did they not submit the paper to the Journal of Climate, where the most rigorous peer review would have been exercised?

But more to the point of their science. Their argument is that tropical Cumulonimbus (thunderstorm) clouds procuce less high-level cirrus-cloud outflow when sea surface temperatures (SST’s) are warmer and atmospheric water vapor is higher. This argument hinges on the contention that more water vapor means greater density of water droplets in the active rising updraft of the storm clouds. In turn, this argument requires that the greater density of droplets produces a greater likelihood of precipitation-sized droplets forming by the collision/coalescence process.

What this argument fails to consider is that the greater SST also produces a more vigorous updraft, so that the rising moist air has less time in which the collision/coalescence process can work before the air reaches the upper cloud layers where spontaneous ice nucleation takes place (at somewhere around -40C, reached near the top of the troposphere). When the droplets turn to ice, they are much more likely to “blow off” into the cirrus anvil of the storm rather than fall as precipitiation.

So there can be a significant trade-off between competing processes. The Lin et al. results are much more consistent with an expected balance, or trade-off, between these processes. We await further, still more sophisticated studies to resolve the issue.

I’m betting that Lin et al. are right, simply because of my long memory. I arrived on the meteorological scene as a fresh graduate student at Colorado State U. in time to become actively involved in the National Hail Research Experiment in the early 1970′s. This was an experiment which aimed to test the hypothesis that cloud seeding with silver iodide could suppress hail by creating an excess of nucleating embryos that would compete for the available cloud water (and thus keep all the hydrometeors smaller) — more precipitation, in fewer big “globs” of hail. This hypothesis was quite quickly rejected when results began to conflict (there was more and bigger hail, or at least no detectable hail suppression as a result of the seeding) and it became understood that the seeding also produced stronger updrafts (due to the accelerated release of the latent heat of freezing by the silver iodide seeding), which, in turn, produced an environment which was conducive to the formation of even larger hailstones.

The greater lesson: Cloud microphysics and cloud updraft dynamics interact with surface processes in very complex and unexpected ways which defy simple hypotheses.

== By Peter J. Wetzel==



 
 

Offline JP

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Debate over what JP?

???

I didn't say anything about debating...
 

Offline yor_on

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My bad then.
 

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