NCAR scientist admits IPCC may be wrong on clouds, may have a net cooling effect instead of warming
…New paper finds the natural Pacific Decadal Oscillation controls North American temperatures via changes in cloud cover: Published in Atmospheric Research
New paper finds the natural Pacific Decadal Oscillation controls North American temperatures via changes in cloud cover
http://hockeyschtick.blogspot.com/2013/10/new-paper-finds-natural-pacific-decadal.html
A paper published today in Atmospheric Research describes a mechanism by which changes in the natural Pacific Decadal Oscillation [PDO] affect air temperatures and water vapor, which subsequently affects cloudiness over North America [planetary albedo], and therefore land surface temperatures. As noted by Dr. Roy Spencer in his book,
“The most obvious way for warming to be caused naturally is for small, natural fluctuations in the circulation patterns of the atmosphere and ocean to result in a 1% or 2% decrease in global cloud cover. Clouds are the Earth’s sunshade, and if cloud cover changes for any reason, you have global warming — or global cooling.”
According to the authors, “The TCM [thermodynamic model] generates a kind of atmospheric bridge by which the SST [sea surface temperature] produces a T7A [change in air temperature], the consequent condensation of water vapour anomaly and the corresponding εA [cloudiness] over the continent, affecting the planetary albedo and therefore the LST [land surface temperature].”
Fig. 1. PDO index for the summers (average of June, July and August) based on the CAF for SST over the North Pacific region during a period of 105 years, from 1900 to 2004 (ftp://ftp.atmos.washington.edu/mantua/pnw_impacts/INDICES/PDO). The global warming signal has been removed from the data. The upward bars indicate years with positive index, and the downward bars indicate years with negative index.
Simulation of the PDO effect on the North America summer climate with emphasis on Mexico
Víctor M. Mendozaa, ,
Berta Odaa,
René Garduñoa,
Elba E. Villanuevaa,
Julián Adema, b
a Centro de Ciencias de la Atmósfera, UNAM, Ciudad Universitaria 04510, México DF, México
b Member of El Colegio Nacional, México
Highlights
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A thermodynamic model simulates the effect of the PDO phases on summer variables of Mexico.
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Combined effect of cloudiness and evaporation according to the soil moisture during the y phases.
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Cloudiness anomalies form an atmospheric bridge.
Abstract
Five composite anomaly fields (CAF) are built for the summer of each Pacific Decadal Oscillation (PDO) phase: skin temperature; air temperature (T7), zonal (u7) and meridional (v7) wind at the 700 mb level; and precipitation (R).
An energy balance model, named Thermodynamic Climate Model (TCM), is integrated on the NH to compute the summer anomalies (sub-index A) of the land surface temperature (LST),T7, u7, v7, R and cloudiness …
New paper finds climate model assumptions on cloud-aerosol interactions may be off by 100%: Published in Atmospheric Chemistry and Physics
New paper finds climate model assumptions on cloud-aerosol interactions may be off by 100%
http://hockeyschtick.blogspot.com/2013/09/new-paper-finds-climate-model.html
A paper published today in Atmospheric Chemistry and Physics demonstrates the huge uncertainties of computer modeling of aerosol–cloud interaction effects, which are one of the “major sources of uncertainty in climate models.” According to the authors, the standard deviation around the mean cloud condensation nuclei varies globally between a minimum of about ± 30% over some marine regions to ± 40–100% over most land areas and high latitudes. This is only one of the factors affecting clouds in climate models, and clouds are but one of the many major uncertainties in climate models.
Dr. Judith Curry points out why climate models might be wrong in her “uncertainty monster” paper, and has pointed out for years the need for realistic assessments of the uncertainty of climate projections. This paper takes one step in that much need direction and shows only a tiny fraction [but still huge] of the “uncertainty monster.” Meanwhile, the IPCC remains blissfully ignorant of the “uncertainty monster” and increases its confidence level from 90 to 95% without any basis in statistical analysis or science.
Atmos. Chem. Phys., 13, 8879-8914, 2013www.atmos-chem-phys.net/13/8879/2013/doi:10.5194/acp-13-8879-2013
The magnitude and causes of uncertainty in global model simulations of cloud condensation nucleiL. A. Lee1, K. J. Pringle1, C. L. Reddington1, G. W. Mann1, P. Stier2, D. V. Spracklen1, J. R. Pierce3, and K. S. Carslaw11Institute for Climate and Atmospheric Science, School of Earth and Environment, University of Leeds, Leeds, UK2Department of Physics, University of Oxford, Oxford, UK3Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado, USAAbstract. Aerosol–cloud interaction effects are a major source of uncertainty in climate models so it is important to quantify the sources of uncertainty and thereby direct research efforts. However, the computational expense of global aerosol models has prevented a full statistical analysis of their outputs. Here we perform a variance-based analysis of a global 3-D aerosol microphysics model to quantify the magnitude and leading causes of parametric uncertainty in model-estimated present-day concentrations of cloud condensation nuclei (CCN). Twenty-eight model parameters covering essentially all important aerosol processes, emissions and representation of aerosol size distributions were defined based on expert elicitation. An uncertainty analysis was then performed based on a Monte Carlo-type sampling of an emulator built for each model grid cell. The standard deviation around the mean CCN varies globally between about ±30% over some marine …
Svensmark’s cosmic ray theory of clouds and global warming looks to be confirmed
…New review paper finds climate sensitivity to CO2 is miniscule
New review paper finds climate sensitivity to CO2 is miniscule
http://hockeyschtick.blogspot.com/2013/08/new-review-paper-finds-climate.html
A new review paper from SPPI and CO2 Science finds on the basis of observations that the response of the climate to radiative forcing from clouds indicates that the “concomitant 20-year change in radiative forcing due to CO2 alone would have had to have been truly miniscule, which suggests that all of the angst manifest by climate alarmists over anthropogenic CO2 emissions may be wholly misplaced” and “it would appear that earth’s climate is much less responsive to changes in radiative forcing than the world’s climate alarmists and most climate modelers claim it to be.”
For the Full Report in PDF Form, please click here.
[Illustrations, footnotes and references available in PDF version]
Excerpts:
Understanding how clouds respond to anthropogenic-induced perturbations of our planet’s atmosphere is of paramount importance in determining the impact of the ongoing rise in the air’s CO2 content on global climate; for as Charlson et al. (2001) have noted, “man-made aerosols have a strong influence on cloud albedo, with a global mean forcing estimated to be of the same order (but opposite in sign) as that of greenhouse gases.” And because of the great importance of this complex subject, this summary presents a brief review of a number of scientific papers that address various aspects of this crucial issue.
he estimated cooling power of these aerosols -which they said was generally believed to be equivalent to the strength of the warming effect of all anthropogenic greenhouse gases – may actually be too conservative.
Although real-world studies thus continue to elucidate the workings of the planet’s complex climate system and improve our understanding of it, there continue to be major problems with computer models that attempt to mimic it.
Because the net global effect of cloud is cooling, any widespread increase in the amount of overcast days could reduce air temperature globally, while local overcast conditions could do so locally.
Finally, Palle et al. note that the increase in radiative forcing produced by the concentration increases experienced by all greenhouse gases since 1850 was something on the order of only 2.5 Wm-2. Compared to the increase in radiative forcing that may have been experiencedbetween 1985 and 2005 as a result of observed changes in total cloud amount and the fractions of clouds located at different elevations (~11 Wm-2, according to the data and analyses of Palle …
Analysis: ‘Climate science’ now hunting for cooling effects – and finds the brightness of clouds
…Settled science: New study ‘shows that atmospheric gases can help clouds form in a way no one had ever considered’
‘…& that an observed decrease in cloud cover alone could account for all global warming observed since ice age scare of 1970’s’
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Norway Data Shows Earth’s Global Warming Less Severe Than Feared — Global temps leveled off & ‘ocean water temperature has also stabilized’
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New paper finds climate in Tibet was more stable in 20th century than prior — Published in Climate of the Past
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New paper finds more evidence of the ‘poor performance’ of climate models — ‘Paper published in the Journal of Climate
As Dr. Roy Spencer points out in his book, “The most obvious way for warming to be caused naturally is for small, natural fluctuations in the circulation patterns of the atmosphere and ocean to result in a 1% or 2% decrease in global cloud cover. Clouds are the Earth’s sunshade, and if cloud cover changes for any reason, you have global warming — or global cooling.” This new paper is one of many that demonstrate current climate models do not even approach the level of accuracy [within 1 – 2%] or ‘consensus’ required to properly model global cloud cover, and therefore cannot be used as ‘proof’ of anthropogenic global warming, nor relied upon for future projections. Prior posts on clouds and the abject failure of climate models.
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