Mann's latest propaganda: "Global Warming Will Cross a Dangerous Threshold in 2036"

Fraudster Michael Mann has published an article in Scientific American today entitled "Why Global Warming Will Cross a Dangerous Threshold in 2036," subtitled, "Emitting carbon dioxide at current rates will soon push Earth’s temperature up by 2 degrees Celsius. Here’s how to make the calculation yourself."

Mann begins the article with, "If the world continues to burn fossil fuels at the current rate, global warming will rise 2 degrees Celsius by 2036, crossing a threshold that many scientists think will hurt all aspects of human civilization: food, water, health, energy, economy and national security," which suggests the 2C "dangerous threshold" has a scientific basis. In fact, the "2C threshold" was unscientifically plucked out of thin air, as the University of East Anglia’s Phil Jones inadvertently admitted in Climategate 2.0. The UK Met Office subsequently admitted this as well to the Washington Post. 

Mann appears to suggest that global temperatures will increase an additional 2C over the next 22 years from now to 2036, but doesn't mention he's talking about 2C warming total since pre-industrial times. Since the globe has warmed 0.7-0.8C since pre-industrial times, that would be an additional ~1.2C over the next 22 years.

Mann then proceeds in the article to go through his sciencey-sounding calculations to arrive at the dangerous threshold year of 2C warming by 2036, but his radiative calculations are just more hockey stick CAGW propaganda for the following reasons [and others]:

1. Mann uses the repeatedly debunked "IPCC/Myhre formula" for CO2 radiative forcing: 

5.35*ln(CO2end/CO2start)

which has a huge erroneous fudge factor of 5.35 that assumes increased water vapor will cause a positive feedback and increase total radiative forcing from CO2 & water vapor by a factor of 3.8 times. In reality, increased water vapor has a negative feedback cooling effect that more than exceeds any warming effect of CO2. The wet adiabatic lapse rate is only one-half of the dry rate, proving that water vapor has a net cooling effect. Satellite observations also prove the net climate feedbacks are negative, not positive as Mann assumes. 

2. Even if we falsely assume the IPCC formula is correct, and that CO2 levels will rise at the same slightly exponential rate of e^.3311, CO2 levels in 2036 would be about 431ppm. Plugging this into the IPCC formula results in 5.35*ln(431/400)= 0.4W/m2. According to the IPCC, each additional W/m2 radiative forcing increases surface temperature 0.75C. Thus, 0.4W/m2 radiative forcing would, according to the IPCC, raise global temperature 0.4*.75=0.3C. 

Global warming of 0.3C plus 0.8C since pre-industrial times would total to 1.1C, only about one-half of the 2C increase that Mann exaggerates below. 

Even if radiative forcing did control the surface temperature [it doesn't- convection, phase change, pressure, atmospheric mass do], Mann's radiative forcing calculations are exaggerated by at least 3.8 times due to false assumptions of water vapor positive feedback. Mann's claims are once again shown to be just more hockey stick propaganda, oblivious to the abject failure of climate models based upon these same calculations.

UPDATE: Steven Goddard has graphed Mann's ridiculous assumptions on CO2 sensitivity to 2036 in comparison to observations:

Why Global Warming Will Cross a Dangerous Threshold in 2036

Emitting carbon dioxide at current rates will soon push Earth’s temperature up by 2 degrees Celsius. Here’s how to make the calculation yourself

Mar 18, 2014 |By Michael E. Mann

If the world continues to burn fossil fuels at the current rate, global warming will rise 2 degrees Celsius by 2036, crossing a threshold that many scientists think will hurt all aspects of human civilization: food, water, health, energy, economy and national security. In my article "False Hope" in the April 2014 Scientific American, I reveal dramatic curves that show why the world will reach this temperature limit so quickly, and also why the recent slowdown in the rate of temperature increase, if it continues, will only buy us another 10 years.

These numbers come from calculations made by me and several colleagues. We plugged values of Earth’s “equilibrium climate sensitivity”—a common measure of the heating effect of greenhouse gases—into a so-called energy balance model. Scientists use the model to investigate possible climate scenarios.

You can try this exercise yourself. The text below explains the variables and steps involved. You can download the climate data here and the model code here. And you can compare your results with mine, which are here. You can also change the variables to see what other future scenarios are possible. One note: the model runs on MatLab software, which can be obtained here.

We employed a simple zero-dimensional Energy Balance Model (“EBM”—see references 1 through 5 below) of the form

C dT/dt = S(1-a)/4 + F_GHG -A-B T + w(t)      

to model the forced response of the climate to estimate natural and anthropogenic radiative forcing.

T is the temperature of Earth’s surface (approximated as the surface of a 70-meter-depth, mixed-layer ocean covering 70 percent of Earth’s surface area).  C = 2.08 x 10⁸J K^-1m^-2 and is an effective heat capacity that accounts for the thermal inertia of the mixed-layer ocean, but does not allow for heat exchange with the deep ocean as in more elaborate “upwelling-diffusion models” (ref. 6). S ≈ 1370 Wm^-2 is the solar constant, and a ≈ 0.3 is the effective surface albedo. F_GHG is the radiative forcing by greenhouse gases, and w(t)  represents random weather effects, which was set to zero to analyze the pure radiative forced response.

The linear “gray body” approximation (ref. 3) LW = A+B T was used to model outgoing longwave radiation in a way that accounts for the greenhouse effect. The choice A = 221.3 WK^-1m^-2 and B = 1.25 Wm^-2 yields a realistic preindustrial global mean temperature T = 14.8 ^oC and an equilibrium climate sensitivity (ECS) of  DT_2xCO2 = 3.0^oC, consistent with midrange estimates by the International Panel on Climate Change (ref. 7).  B can be varied to change the ECS of the EBM. For example, the higher value B = 1.5 Wm^-2 yields a more conservative ECS of  DT_2xCO2 = 2.5^oC.

Energy Balance Model Simulations

Historical Simulations. The model was driven with estimated annual natural and anthropogenic forcing over the years A.D. 850 to 2012. Greenhouse radiative forcing was calculated using the approximation (ref. 8) F_GHG = 5.35log(CO₂e/280), where 280 parts per million (ppm) is the preindustrial CO₂ level and CO₂e is the “equivalent” anthropogenic CO₂. We used the CO₂ data from ref. 9, scaled to give CO₂e values 20 percent larger than CO₂ alone (for example, in 2009 CO₂ was 380 ppm whereas CO₂ewas estimated at 455 ppm). Northern Hemisphere anthropogenic tropospheric aerosol forcing was not available for ref. 9 so was taken instead from ref. 2, with an increase in amplitude by 5 percent to accommodate a slightly larger indirect effect than in ref. 2, and a linear extrapolation of the original series (which ends in 1999) to extend though 2012.

Estimated past changes in solar irradiance were prescribed as a change in the solar constant S whereas forcing by volcanic aerosols was prescribed as a change in the surface albedo a. Solar and volcanic forcing were taken from the General Circulation Model (GCM) simulation of ref. 3 described in the section above, with the following modifications: (1) solar forcing was rescaled under the assumption of a 0.1 percent change from Maunder Minimum to present, more consistent with recent estimates (ref. 9); (2) volcanic forcing was applied as the mean of the latitudinally varying volcanic forcing of ref. 9; (3) values for both series were updated through 2012.

Future Projections: For the purpose of the “business as usual” future projections, we have linearly extrapolated the CO₂ radiative forcing forward to 2100, based on the trend over the past decade (which is roughly equivalent, from a radiative forcing standpoint, to a forward projection of the exponential historical trajectory of CO2 emissions). We assume constant solar output, and assume no climatically significant future volcanic eruptions.

We have assumed that tropospheric aerosols decrease exponentially from their current values with a time constant of 60 years. This gives a net anthropogenic forcing change from 2000 to 2100 of 3.5 Wm^-2, roughly equivalent to the International Panel on Climate Change’s 5^th assessment report “RCP6” scenario, a future emissions scenario that assumes only modest efforts at mitigation.

Stabilization Scenarios: For the stabilization scenarios, we relax (with a 20-year time constant) the CO₂ concentration to a maximum specified value at 2100. We considered cases both where the anthropogenic tropospheric aerosol burden is assumed to (a) decrease exponentially from their current values with a time constant of 60 years, as in the future projections discussed in the previous section, and alternatively (b) remain constant at its current value.

Additional Details. Sensitivity analyses of the historical simulations were performed by Mann et al 2012 (ref.  4) with respect to (i) the equilibrium climate sensitivity assumed (varied from  DT_2xCO2 = 2-4 ^oC); the (ii) solar scaling (0.25 percent in place of 0.1 percent Maunder Minimum to present change); (iii) the volcanic aerosol loading estimates used; and (iv) the scaling of volcanic radiative forcing with respect to aerosol loading to account for possible size distribution effects. All of the alternative choices described above were found to yield qualitatively similar results.

Matlab source code for the energy balance model, data used in the calculations and the simulation results discussed in the Scientific American article are available at:www.meteo.psu.edu/holocene/public_html/supplements/EBMProjections

Stop denying climate science and ACT! (before people realize it’s a scam)

Stop denying climate science and ACT! (before people realize it’s a scam)

By Paul Driessen, September 2, 2013

The full-court press is on. Alarmist scientists, politicians, pressure groups, newspapers, ministers, rabbis and bureaucrats want Americans to “stop stalling” on climate change. They demand that we embrace “revenue-neutral” carbon taxes and carbon dioxide regulations, before it’s “too late” to prevent “catastrophic” global warming, “monster” storms and rising seas that will “inundate our coastal cities.”

Anyone dissenting from this “call to action” is a climate change “denier”—a pejorative devised to vilify and silence anyone who rejects this agenda, by linking our views to Holocaust denial. What nonsense.

All of us “deniers” know climate change is real and has been throughout Earth’s many cycles of warming and cooling, storms and droughts, ice ages and little ice ages. Striations (scratches) on a chunk of Niagara Escarpment limestone that I dug out a mile from my boyhood home memorialize stones dragged by the last glacier that buried Wisconsin under a mile of ice. Countless climate changes have buffeted our Earth.

What we deny are assertions that human carbon dioxide emissions have replaced the myriad of complex, interrelated planetary, solar and cosmic forces that caused previous climate reverberations, and that what we are experiencing now is unprecedented and likely to be catastrophic.

Not one of the alarmist claims is supported by actual observations or scientificevidence. Even worse, the claims are getting more ridiculous with every passing day: “children aren’t going to know what snow is,” crime is rising, oceans won’t smell the same, and storms are getting worse—because of global warming. 

Contrary to the hype and hysteria, our planet stopped warming 16 years ago

Contrary to the hype and hysteria, our planet stopped warming 16 years ago, even as atmospheric carbon dioxide levels continued to climb. That prompted climate catastrophists to start talking about “climate change” and blame every “extreme weather” event on CO2 emissions.

As I have pointed out before, far from being a “dangerous pollutant” (as President Obama and EPA keep saying), carbon dioxide makes all life on Earth possible. It makes food crops and other plants grow faster and better, loads them with more nutrients, helps them survive droughts, and makes our planet greener.

This trace gas has almost nothing to do with planetary warming or climate change. But it’s worth noting that the United States has slashed its CO2 emissions more than almost any other country—sending them back to where they were 30 years ago, thanks to the environmentalists’ latest target: fracking! And the daily human contribution of CO2 to our atmosphere is equivalent to a penny out of $1 million!

CO2 levels have “soared” to 400 ppm (0.04% of Earth’s atmosphere) not because of the USA or other developed countries—but because China, India and dozens of other countries are working desperately to lift billions of people out of abject poverty. To do that, they need fossil fuels, which provide 80% of the energy that makes modern civilization and living standards possible—and these countries are not going to slash their hydrocarbon use. To suggest otherwise reflects callous contempt for the needs of families that want to take their rightful places among Earth’s healthy and prosperous people.

No one would suggest that the absence of extreme weather events over a particular time period is due to humans. However, recent history certainly contradicts incessant claims that our weather is getting worse. In fact, no category 3 or higher hurricane has struck the United States in eight years, the longest such stretch since the Civil War. With only a couple of exceptions earlier this summer, the US is enjoying its longest respite from major tornadoes in decades. We are also witnessing the highest AugustArctic sea ice extent since 2006, amid the coldest summer on record at the North Pole;record August lows for Alert and Eureka, in Nunavut, BC; and record highs for the extent of August sea ice in Antarctica.

Equally fascinating, most of the record high temperatures that the alarmists are trumpeting beat the previous records, mostly set in the 1930s, by mere hundredths of a degree. Yet, somehow that’s news.

As to oceans inundating coastal communities, Topex Poseidon satellites show virtuallyno rise in sea levels between 1993 and 2001, and the EU’s Envisat satellites show no rise from 2003 through 2011. The steady 2-3 mm per year rise in sea level, it turns out, is because scientists “adjust” the raw data (always upward, never down, for some reason). But even 200-300 mm (8-12 inches) per century, or by the year 2100, is a far cry from the 3-20 feet that President Obama and former VP Al Gore have warned us about. Even Mr. Obama was off a few years when he said June 2008 was “the moment when the rise of the oceans began to slow.” But it’s one more climate cataclysm that we can erase from our worry list—especially compared to the 400 feet that the world’s oceans have risen since the end of the last ice age.

(Mr. Gore is also famous for misinforming his 2009 “Tonight Show” audience that the Earth’s interior is “really hot, several million degrees”—the core is actually 9,000 degrees F—and for refusing to debate anyone on climate change or even take audience questions that he has not preapproved. Perhaps in his defense, Nobel Laureate Gore managed only a C+ and a D in the only science courses he ever took.)

If it’s “weird weather” you seek, just peruse Richard Keene’s fascinating weather guides, Skywatch East and Skywatch West, for numerous examples of wild and wacky weather in the USA. For more examples, check out the Tri-State Twister and Children’s Blizzard, or consult the Nongovernmental International Panel on Climate Change 2011 interim report, Climate Change Reconsidered. You will be amazed at how different the facts are from the fallacies, fibs and fear mongering you find in the “mainstream media.”

No tax that penalizes people and businesses for using fossil fuels is “revenue neutral.”

One final point. No tax that penalizes people and businesses for using fossil fuels is “revenue neutral.” Any such tax or regulation kills profits and jobs, turns full-time jobs into part-timers, and adversely affects people’s health and well-being. Millions of families cannot heat and cool their homes properly, pay their rent, mortgage or other bills, take vacations, or save for retirement. The increasing stress results in sleep deprivation, poor nutrition, more commuting, higher incidences of depression and alcohol, drug, spousal and child abuse, lower life expectancies and higher suicide rates. Climate taxes and regulations also force us to spend billions subsidizing environment unfriendly biofuels, wind and solar energy.

That’s an intolerably high price to pay, for “protection” from illusory and exaggerated climate dangers.

Climate alarmists are trying to sucker, snooker and stampede us into taking “immediate action” on job and economy-strangling taxes and restrictions, before more people catch on to what’s really happening. This protection racket is one more example of passing a law, so that we can find out what’s in it. We simply cannot afford to let science continue being coopted to serve anti-hydrocarbon political agendas.

Demands that we “stop stalling” on “catastrophic manmade climate change” have nothing to do with preventing warming and cooling, storms and droughts that have been “real” since time immemorial. They have everything to do with regulating and restricting the use of hydrocarbons that provide 80% of the energy that makes modern civilization and living standards possible. They have everything to do with giving politicians, bureaucrats and pressure groups more money and more control over our lives and economy—but with no accountability for the lies, mistakes, job losses, ill health and deaths that are inevitable as US living standards deteriorate, and Third World lives remain destitute and desperate.

Computer models and scary predictions are not evidence

Computer models and scary predictions are not evidence. Basing energy and economic decisions on climate models is akin to betting your life’s savings on a computer model that focuses on middle linebackers and ignores quarterbacks and offensive lines, in predicting the Buffalo Bills will win the 2014 and 2015 Super Bowls—and when the prediction falls flat insisting that the Bills really did win, and reality must be “adjusted” to make it conform with the predictions.

Climate “deniers” and rationalists should support Senator Ron Johnson (R-WI) and other politicians and scientists who are under constant attack by climate alarmists, for daring to dissent from approved orthodoxy. Their vigilance and determination are all that stand between energy and economic sanity—and America heading down the same destructive path that Europe has trod for the past two decades.

New paper finds climate model results are 'substantially' erroneous because they assume the Earth is flat

A new paper published in Theoretical and Applied Climatology finds "substantial" differences between conventional climate models that assume the Earth is flat as compared to a model that accounts for 3-D geography over mountainous regions. The authors use topography data over the Tibetan Plateau in their 3-D model and find deviations in net solar radiation at the surface "range from −150 to 180 W/m2 over the Tibetan Plateau. The local deviation in the solar flux could lead to earlier onset of convection and more small-scale circulation." The authors "demonstrate that the entire Tibetan Plateau would receive more solar flux by about 14 W/m2, if its 3-D mountain structure was included in the calculations, which would result in larger sensible and latent heat transfer from the surface to the atmosphere." By way of comparison, 14 W/m2 is about four times greater than the IPCC alleged forcing from doubled CO2 levels. The paper's findings are ironic in light of Obama's claims that CAGW skeptics are members of the Flat Earth Society. 

Excerpts:

We show that over the Tibetan Plateau on 21 March 2001 (spring equinox), the largest deviations in the direct flux with reference to plane-parallel results are about −200 and 200 W/m2 on the shaded and sunward sides of the mountains, respectively. Over high-albedo snow-covered areas, the largest deviations in the direct-reflected- and coupled fluxes are about 200 and 40 W/m2 , respectively. Combining all five components, deviations in the net surface solar flux range from −150 to 180 W/m2 over the Tibetan Plateau. The local deviation in the solar flux could lead to earlier onset of convection and more small-scale circulation. The domain averaged deviations in surface solar fluxes over the whole Tibetan Plateau is on the order of 14 W/m2 at noon of spring equinox, in which the dominant term is the direct-reflected flux, while the contribution of other components is almost 0. This shows that the surface receives more solar energy than the results calculated from conventional 1-D models, which could lead to stronger convection and enhanced snowmelt rate. While the deviations discussed above are based on the grid size of 10×10 km2, significant deviations on the order of 20 W/m2 can be found even at a resolution of 100×100 km2. 

Finally, while the current parameterization approach has been developed for clear sky surface solar flux, it should be noted that because the direct- and direct-reflected fluxes do not encounter atmospheric multiple scattering, the regression equations for these fluxes remain unchanged in cloudy conditions. As a first approximation, the coefficients obtained for clear sky conditions can be applied directly to cloudy conditions. In mountainous areas, however, cloud issues are more complex and require further research and analysis.

Theoretical and Applied Climatology

July 2013, Volume 113, Issue 1-2, pp 95-103

Impact of 3-D topography on surface radiation budget over the Tibetan Plateau

• Wei-Liang Lee, 
• K. N. Liou, 
• Chia-chi Wang

The 3-D complex topography effect on the surface solar radiative budget over the Tibetan Plateau is investigated by means of a parameterization approach on the basis of “exact” 3-D Monte Carlo photon tracing simulations, which use 90 m topography data as building blocks. Using a demonstrative grid size of 10 × 10 km2, we show that differences in downward surface solar fluxes for a clear sky without aerosols between the 3-D model and the conventional plane-parallel radiative transfer scheme are substantial, on the order of 200 W/m2 at shaded or sunward slopes. Deviations in the reflected fluxes of the direct solar beam amount to about +100 W/m2 over snow-covered areas, which would lead to an enhanced snowmelt if the 3-D topography effects had been accounted for in current climate models. We further demonstrate that the entire Tibetan Plateau would receive more solar flux by about 14 W/m2, if its 3-D mountain structure was included in the calculations, which would result in larger sensible and latent heat transfer from the surface to the atmosphere.

Most recent 100 posts on the abject failure of climate models

New paper finds climate models are getting worse rather than better

A paper published today in Geophysical Research Letters finds that the latest climate models are performing even worse than the earlier generations of climate models in predicting "both the mean surface air temperature as well as the frequency of extreme monthly mean temperature events due to climate warming." The author hypothesizes the reasons for this are that attempts in the latest generation of models to reproduce observed changes in Arctic sea ice are causing "significant and widening discrepancy between the modeled and observed warming rates outside of the Arctic," i.e. they have improved Arctic simulation at the expense of poorly simulating the rest of the globe. The paper adds to hundreds of other peer-reviewed papers demonstrating the abject failure of climate models.

Emerging selection bias in large-scale climate change simulations

Kyle L. Swanson

Abstract: Climate change simulations are the output of enormously complicated models containing resolved and parameterized physical processes ranging in scale from microns to the size of the Earth itself. Given this complexity, the application of subjective criteria in model development is inevitable. Here we show one danger of the use of such criteria in the construction of these simulations, namely the apparent emergence of a selection bias between generations of these simulations. Earlier generation ensembles of model simulations are shown to possess sufficient diversity to capture recent observed shifts in both the mean surface air temperature as well as the frequency of extreme monthly mean temperature events due to climate warming. However, current generation ensembles of model simulations are statistically inconsistent with these observed shifts, despite a marked reduction in the spread among ensemble members that by itself suggests convergence towards some common solution. This convergence indicates the possibility of a selection bias based upon warming rate. It is hypothesized that this bias is driven by the desire to more accurately capture the observed recent acceleration of warming in the Arctic and corresponding decline in Arctic sea ice. However, this convergence is difficult to justify given the significant and widening discrepancy between the modeled and observed warming rates outside of the Arctic.

New paper finds climate models need another 5 to 50 years of research to predict impacts of climate change

A new paper published in Environmental Research Letters finds that current climate models are not able to predict regional, seasonal temperature and precipitation changes and have huge "mean errors between 1 and 18 °C." Therefore, according to the authors, the models are especially unable to predict the impacts of regional temperature and precipitation changes. According to the authors, "no single [climate model] matches observations in more than 30% of the areas for monthly precipitation and wet-day frequency, 50% for diurnal range and 70% for mean temperatures." The majority of the IPCC AR4 report discusses the alleged regional impacts of climate change based on these same models, but according to the authors, the models won't be ready to predict the impacts of climate change for another 5 to 50 years, stating, "we estimate that at least 5–30 years of [computer modeling research] is required to improve regional temperature simulations and at least 30–50 years for precipitation simulations, for these to be directly input into impact models."

Implications of regional improvement in global climate models for agricultural impact research

Julian Ramirez-Villegas et al

Full text PDF (1.27 MB)

Abstract: Global climate models (GCMs) have become increasingly important for climate change science and provide the basis for most impact studies. Since impact models are highly sensitive to input climate data, GCM skill is crucial for getting better short-, medium- and long-term outlooks for agricultural production and food security. The Coupled Model Intercomparison Project (CMIP) phase 5 ensemble is likely to underpin the majority of climate impact assessments over the next few years. We assess 24 CMIP3 and 26 CMIP5 simulations of present climate against climate observations for five tropical regions, as well as regional improvements in model skill and, through literature review, the sensitivities of impact estimates to model error. Climatological means of seasonal mean temperatures depict mean errors between 1 and 18 ° C (2–130% with respect to mean), whereas seasonal precipitation and wet-day frequency depict larger errors, often offsetting observed means and variability beyond 100%. Simulated interannual climate variability in GCMs warrants particular attention, given that no single GCM matches observations in more than 30% of the areas for monthly precipitation and wet-day frequency, 50% for diurnal range and 70% for mean temperatures. We report improvements in mean climate skill of 5–15% for climatological mean temperatures, 3–5% for diurnal range and 1–2% in precipitation. At these improvement rates, we estimate that at least 5–30 years of CMIP work is required to improve regional temperature simulations and at least 30–50 years for precipitation simulations, for these to be directly input into impact models. We conclude with some recommendations for the use of CMIP5 in agricultural impact studies.

Take away lesson: Spend billion$ more on climate research to improve on the abject failure of climate models

New paper finds IPCC climate models unable to reproduce solar radiation at Earth's surface

A new paper published in the Journal of Geophysical Research - Atmospheres finds the latest generation of IPCC climate models were unable to reproduce the global dimming of sunshine from the ~ 1950s-1980s, followed by global brightening of sunshine during the 1990's. These global dimming and brightening periods explain the observed changes in global temperature over the past 50-60 years far better than the slow steady rise in CO2 levels. The authors find the models underestimated dimming by 80-85% in comparison to observations, underestimated brightening in China and Japan as well, and that "no individual model performs particularly well for all four regions" studied. Dimming was underestimated in some regions by up to 7 Wm-2 per decade, which by way of comparison is 25 times greater than the alleged CO2 forcing of about 0.28 Wm-2 per decade. The paper demonstrates climate models are unable to reproduce the known climate change of the past, much less the future, that the forcing from changes in solar radiation at the Earth surface is still far from being understood and dwarfs any alleged effect of increased CO2.

Prior posts on the abject failure of climate models

Evaluation of multidecadal variability in CMIP5 surface solar radiation and inferred underestimation of aerosol direct effects over Europe, China, Japan and India

R. J. Allen 1, J. R. Norris 2, M. Wild 3

DOI: 10.1002/jgrd.50426

Abstract: Observations from the Global Energy Balance Archive indicate regional decreases in all sky surface solar radiation from ~1950s-1980s, followed by an increase during the 1990s. These periods are popularly called dimming and brightening, respectively. Removal of the radiative effects of cloud cover variability from all sky surface solar radiation results in a quantity called “clear sky proxy” radiation, in which multidecadal trends can be seen more distinctly, suggesting aerosol radiative forcing as a likely cause. Prior work has shown climate models from the Coupled Model Intercomparison Project 3 (CMIP3) generally underestimate the magnitude of these trends, particularly over China and India. Here, we perform a similar analysis with 173 simulations from 42 climate models participating in the new CMIP5. Results show negligible improvement over CMIP3, as CMIP5 dimming trends over four regions–Europe, China, India and Japan–are all underestimated. This bias is largest for both India and China, where the multi-model mean yields a decrease in clear sky proxy radiation of −1.3 ± 0.3 and −1.2 ± 0.2 W m−2 decade−1, respectively, compared to observed decreases of −6.5 ± 0.9 and −8.2 ± 1.3 W m−2 decade−1. Similar underestimation of the observed dimming over Japan exists, with the CMIP5 mean dimming ~20% as large as observed. Moreover, not a single simulation reproduces the magnitude of the observed dimming trend for these three regions. Relative to dimming, CMIP5 models better simulate the observed brightening, but significant underestimation exists for both China and Japan. Overall, no individual model performs particularly well for all four regions. Model biases do not appear to be related to the use of prescribed versus prognostic aerosols, or to aerosol indirect effects. However, models exhibit significant correlations between clear sky proxy radiation and several aerosol-related fields, most notably aerosol optical depth (AOD), and absorption AOD. This suggests model underestimation of the observed trends is related to underestimation of aerosol direct radiative forcing and/or deficient aerosol emission inventories.

New paper finds models don't reproduce climate changes of the Holocene Climatic Optimum

A paper published today in Climate of the Past finds climate models are unable to reproduce known climate change during the mid-Holocene Climatic Optimum, a warmer period than the present. According to the authors, "our results for the mid-Holocene are substantially negative, with the models failing to reproduce the observed changes with any degree of skill," and "climate science is now facing the challenge of predicting future changes on regional scales, which includes the requirement to correctly model vegetation and many other feedbacks. Our results provide some sobering evidence of the limits to the ability of current models to accurately reproduce the local patterns of change that are seen in paleoclimate data."

Prior posts on the abject failure of climate models

Clim. Past, 9, 811-823, 2013
www.clim-past.net/9/811/2013/
doi:10.5194/cp-9-811-2013

Skill and reliability of climate model ensembles at the Last Glacial Maximum and mid-Holocene

J. C. Hargreaves¹, J. D. Annan¹, R. Ohgaito¹, A. Paul², and A. Abe-Ouchi^1,3
1RIGC/JAMSTEC, Yokohama Institute for Earth Sciences, Yokohama, Japan
²University of Bremen, Bremen, Germany
³AORI, University of Tokyo, Tokyo, Japan

Abstract. Paleoclimate simulations provide us with an opportunity to critically confront and evaluate the performance of climate models in simulating the response of the climate system to changes in radiative forcing and other boundary conditions. Hargreaves et al. (2011) analysed the reliability of the Paleoclimate Modelling Intercomparison Project, PMIP2 model ensemble with respect to the MARGO sea surface temperature data synthesis (MARGO Project Members, 2009) for the Last Glacial Maximum (LGM, 21 ka BP). Here we extend that work to include a new comprehensive collection of land surface data (Bartlein et al., 2011), and introduce a novel analysis of the predictive skill of the models. We include output from the PMIP3 experiments, from the two models for which suitable data are currently available. We also perform the same analyses for the PMIP2 mid-Holocene (6 ka BP) ensembles and available proxy data sets.

Our results are predominantly positive for the LGM, suggesting that as well as the global mean change, the models can reproduce the observed pattern of change on the broadest scales, such as the overall land–sea contrast and polar amplification, although the more detailed sub-continental scale patterns of change remains elusive. In contrast, our results for the mid-Holocene are substantially negative, with the models failing to reproduce the observed changes with any degree of skill. One cause of this problem could be that the globally- and annually-averaged forcing anomaly is very weak at the mid-Holocene, and so the results are dominated by the more localised regional patterns in the parts of globe for which data are available. The root cause of the model-data mismatch at these scales is unclear. If the proxy calibration is itself reliable, then representativity error in the data-model comparison, and missing climate feedbacks in the models are other possible sources of error.

 Final Revised Paper (PDF, 2495 KB)   Supplement (131 KB)   Discussion Paper (CPD)   Special Issue

New paper finds climate models exaggerate global warming compared to historical data

A paper published today in the Journal of Geophysical Research - Atmospheres admits that state-of-the-art climate models exaggerate alleged warming from greenhouse gases, finding the models "overestimate the observed temperature change" in comparison to historical data since 1850. The authors also find the various models have a "large spread" or widely divergent temperature projections. The paper adds to hundreds of other peer-reviewed papers demonstrating the abject failure of climate models

Evaluating adjusted forcing and model spread for historical and future scenarios in the CMIP5 generation of climate models

Abstract: We utilize energy budget diagnostics from the Coupled Model Intercomparison Project phase 5 (CMIP5) to evaluate the models' climate forcing since preindustrial times employing an established regression technique. The climate forcing evaluated this way, termed the adjusted forcing (AF), includes a rapid adjustment term associated with cloud changes and other tropospheric and land-surface changes. We estimate a 2010 total anthropogenic and natural AF from CMIP5 models of 1.9 ± 0.9 W m⁻² (5–95% range). The projected AF of the Representative Concentration Pathway simulations are lower than their expected radiative forcing (RF) in 2095 but agree well with efficacy weighted forcings from integrated assessment models. The smaller AF, compared to RF, is likely due to cloud adjustment. Multimodel time series of temperature change and AF from 1850 to 2100 have large intermodel spreads throughout the period. The intermodel spread of temperature change is principally driven by forcing differences in the present day and climate feedback differences in 2095, although forcing differences are still important for model spread at 2095. We find no significant relationship between the equilibrium climate sensitivity (ECS) of a model and its 2003 AF, in contrast to that found in older models where higher ECS models generally had less forcing. Given the large present-day model spread, there is no indication of any tendency by modelling groups to adjust their aerosol forcing in order to produce observed trends. Instead, some CMIP5 models have a relatively large positive forcing and overestimate the observed temperature change.

New paper notes long-term climate change may be 'inherently unpredictable'

A paper published today in the Journal of the Atmospheric Sciences reveals the abject failure of climate models to project either the transient or long-term ["equilibrium"] climate change from greenhouse gases. The paper notes, "The Equilibrium Climate Sensitivity (ECS) has a large uncertainty among models participating in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) and has recently been presented as “inherently unpredictable”. One way to circumvent this problem is to consider the Transient Climate Response (TCR)[short-term response to greenhouse gases]. However, the TCR among AR4 models also differ by more than a factor of 2." Furthermore, the authors find that the projections vary by 30% even within the same model with the same equilibrium climate sensitivity."

Prior posts on the abject failure of climate models

Journal of the Atmospheric Sciences 2013 ; e-View

doi: http://dx.doi.org/10.1175/JAS-D-12-0338.1

Transient Climate Response in Coupled Atmospheric-Ocean General Circulation Models

Mao-Chang Liang,^1,2,* Li-Ching Lin,³ Ka-Kit Tung,⁴ Yuk L. Yung,⁵ and Shan Sun⁶

¹ Research Center for Environmental Changes, and Institute of Astronomy and Astrophysics, Academia Sinica, Taiwan

² Graduate Institute of Astronomy, National Central University, Taiwan

³ Institute of Earth Sciences, Academia Sinica, Taiwan

⁴ Department of Applied Mathematics, University of Washington, USA

⁵ Division of Geological and Planetary Sciences, California Institute of Technology, USA

⁶ Earth System Research Laboratory, National Oceanic and Atmospheric Administration, USA

Abstract

The Equilibrium Climate Sensitivity (ECS) has a large uncertainty among models participating in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) and has recently been presented as “inherently unpredictable”. One way to circumvent this problem is to consider the Transient Climate Response (TCR). However, the TCR among AR4 models also differ by more than a factor of 2. We argue that the situation may not necessarily be so pessimistic, because much of the inter-model difference may be due the fact that the models were run with their oceans at various stages of flux adjustment with their atmosphere. This is shown by comparing multi-millennium long runs of the Goddard Institute for Space Studies coupled model (GISS-EH) and the Community Climate System Model (CCSM4) with what were reported to AR4. The long model runs here reveal the range of variability (~30%) in their TCR within the same model with the same ECS. The commonly adopted remedy of subtracting the “climate drift” is ineffective and adds to the variability. The culprit is the natural variability of the control runs, which exists even at quasi-equilibration. Fortunately, for simulations with multi-decadal time horizon, robust solutions can be obtained by branching off thousand-year-long control runs that reach “quasi-equilibration” using a new protocol, which takes advantage of the fact that forced solutions to radiative forcing forget their initial condition after 30-40 years and instead depends mostly on the trajectory of the radiative forcing.

New paper finds more evidence of the 'poor performance' of climate models

A new paper published in the Journal of Climate finds there has been "little to no improvement" in simulating clouds by state-of-the-art climate models. The authors note the "poor performance of current global climate models in simulating realistic [clouds]," and that the models show "quite large biases...as well as a remarkable degree of variation" with the differences between models remaining "large." 

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

Journal of Climate 2012 ; e-View

doi: http://dx.doi.org/10.1175/JCLI-D-12-00451.1

Simulating clouds with global climate models: A comparison of CMIP5 results with CMIP3 and satellite data

Axel Lauer^1,* and Kevin Hamilton^1,2

¹ International Pacific Research Center, University of Hawaii at Manoa, Honolulu, Hawaii

² Department of Meteorology, University of Hawaii at Manoa, Honolulu, Hawaii

Abstract

Clouds are a key component of the climate system affecting radiative balances as well as the hydrological cycle. Previous studies from the Coupled Model Intercomparison Project Phase 3 (CMIP3) showed quite large biases in the simulated cloud climatology affecting all GCMs [global climate models] as well as a remarkable degree of variation among the models, which represented the state-of-the-art circa 2005. Here we measure the progress that has been made in recent years by comparing mean cloud properties, interannual variability, and the climatological seasonal cycle from the CMIP5 models with satellite observations and with results from comparable CMIP3 experiments. We focus on three climate-relevant cloud parameters: cloud amount, liquid water path, and cloud radiative forcing. We show that intermodel differences are still large in the CMIP5 simulations. We find some small improvements of particular cloud properties in some regions in the CMIP5 ensemble over CMIP3. In CMIP5 there is an improved agreement of the modeled interannual variability of liquid water path as well as of the modeled longwave cloud forcing over mid and high latitude oceans with observations. However, the differences in the simulated cloud climatology from CMIP3 and CMIP5 are generally small and there is very little to no improvement apparent in the tropical and subtropical regions in CMIP5.

Comparisons of the results from the coupled CMIP5 models with their atmosphere-only versions run with observed SSTs show remarkably similar biases in the simulated cloud climatologies. This suggests the treatments of subgrid-scale cloud and boundary layer processes are directly implicated in the poor performance of current GCMs [global climate models or general circulation models] in simulating realistic cloud fields.

New paper finds models have it wrong again & predict excessive droughts

A new paper published in Nature finds that "across all six continents studied, afternoon rain falls preferentially over soils that are relatively dry compared to the surrounding area."  The finding is yet another example of negative feedbacks in the climate system that help to stabilize climate. However, climate models are programmed to assume the opposite: that dry areas will become drier and wet areas wetter due to a fictitious positive-feedback mechanism. The authors find that this erroneous positive-feedback assumption results in excessive predictions of drought in computer models, stating,

 "We find no evidence in our analysis of a positive feedback—that is, a preference for rain over wetter soils—at the spatial scale (50–100 kilometres) studied. In contrast, we find that a positive feedback of soil moisture on simulated precipitation does dominate in six state-of-the-art global weather and climate models—a difference that may contribute to excessive simulated droughts in large-scale models."

Related posts on the abject failure of climate computer models

Afternoon rain more likely over drier soils

• Christopher M. Taylor,
• Richard A. M. de Jeu,
• Françoise Guichard,
• Phil P. Harris
• &Wouter A. Dorigo

• Affiliations
• Contributions
• Corresponding author

Nature

 

489,

 

423–426

 

(20 September 2012)

 

doi:10.1038/nature11377

Received

 

19 March 2012 

Accepted

 

29 June 2012 

Published online

 

12 September 2012

Article tools

Land surface properties, such as vegetation cover and soil moisture, influence the partitioning of radiative energy between latent and sensible heat fluxes in daytime hours. During dry periods, soil-water deficit can limit evapotranspiration, leading to warmer and drier conditions in the lower atmosphere^1, 2. Soil moisture can influence the development of convective storms through such modifications of low-level atmospheric temperature and humidity^1, 3, which in turn feeds back on soil moisture. Yet there is considerable uncertainty in how soil moisture affects convective storms across the world, owing to a lack of observational evidence and uncertainty in large-scale models⁴. Here we present a global-scale observational analysis of the coupling between soil moisture and precipitation. We show that across all six continents studied, afternoon rain falls preferentially over soils that are relatively dry compared to the surrounding area. The signal emerges most clearly in the observations over semi-arid regions, where surface fluxes are sensitive to soil moisture, and convective events are frequent. Mechanistically, our results are consistent with enhanced afternoon moist convection driven by increased sensible heat flux over drier soils, and/or mesoscale variability in soil moisture. We find no evidence in our analysis of a positive feedback—that is, a preference for rain over wetter soils—at the spatial scale (50–100 kilometres) studied. In contrast, we find that a positive feedback of soil moisture on simulated precipitation does dominate in six state-of-the-art global weather and climate models—a difference that may contribute to excessive simulated droughts in large-scale models.

Time Mag finally admits 'We've heard warnings about imminent environmental collapse before, and they haven't yet been right'

What the Failure of Rio 20 Means for the Climate

Photo: CHRISTOPHE SIMON / AFP / GettyImages

By Bryan Walsh TIME.com 

Expectations were extremely modest for the Rio+20 Earth Summit that ended last week--and the best thing that might be said about the conference is that it managed to clear that very low bar. Despite the presence of more than 50,000 people and about 100 heads of state and government--though not, notably, U.S. President Barack Obama--the summit produced very little of note. The final statement that was negotiated at Rio--titled "The Future We Want"--was 253 paragraphs of affirmations and entreaties that added up to little more than a plea for something better. The Chinese diplomat Sha Zukang, who headed Rio+20 for the U.N., called the statement "an outcome that makes nobody happy," while environmental NGOs were blunter: "A failure of epic proportions" said Kumi Naidoo, the executive director of Greenpeace International, adding that the statement itself was "the longest suicide note in history."

It's tempting to use the failure of the Rio+20 conference as evidence that international environmental summits and accords are simply unworkable. But it's hardly only environmental issues that are gridlocked at the global level. Just a few days before Rio, the leaders of the world's most powerful countries failed to make much progress on either the European financial crisis or the violence in Syria--two problems that are more immediately pressing than climate change, water shortages, endangered species or just about any other big-picture issue that was kicked around in Rio. If the leaders of the world can't come together to avert what could be the next great global recession or a growing Syrian bloodbath, fixing the infinitely more complex problem of climate change seems all but hopeless.

So how worried should we be? There's no shortage of frightening studies that tell us we're headed for a climate tipping point--we've covered them here at Going Green. But we've heard warnings about imminent environmental collapse before, and they haven't yet been right, as the Danish economist and environmental contrarian Bjorn Lomborg points out in an essay in the latest edition of Foreign Affairs.

Lomborg looks back to an influential 1972 report calledThe Limits to Growth, by the Club of Rome--a blue-ribbon collection of business leaders, scholars and government officials convened at the time by the Italian tycoon Aurielo Peccei. Based on forecasts drawn from computer models developed by the Massachusetts Institute of Technology, the Club of Rome predicted that the world was about to hit a wall on vital natural resources like food and energy, even as it was choked by pollution. A TIME magazine story on the report, headlined "The Worst Is Yet to Be?", captured the grimness, laying out a nightmarish scenario of mass starvation, deindustrialization and general collapse--all to happen within our lifetimes.

Obviously that hasn't occurred. On the whole, humanity is significantly healthier and wealthier than it was 40 years ago--especially in developing nations like China and India, which have seen hundreds of millions of people lifted out of abject poverty. The Club of Rome predicted that the world would effectively run out of vital natural resources like aluminum, oil and natural gas; nothing of that sort has happened either, and some of those resources have actually become less expensive. While there are still 1 billion people who go to bed hungry each day--a number that has crept up recently after falling for years--global calorie availability since the Club of Rome report has increased by more than 25%. "Over the past 40 years," Lomborg writes, "the fraction of the global population that is malnourished has dropped from 35% to less than 16%, and well over 2 billion more people have been fed adequately." When famines and mass starvation do occur, as they have recently in parts of Somalia and Sudan, war and political unrest bear more of the blame than farming failures or environmental degradation.

This isn't to say that the world is better in every way than it was 40 years ago--not remotely. The number of endangered species continues to grow, as do extinctions, so rapidly that some scientists believe we may already be entering the sixth great extinction event. (The last great extinction event occurred 65 millions years ago, when the dinosaurs died off and made way for the mammals.) And while the environmental alarmists have been wrong in the past, there's no guarantee they'll be wrong in the future. Some problems--like carbon emissions--are growing even faster today than the pessimists would have predicted a decade or two ago. The 7 billion people on Earth--led by the 1.2 billion people who live in the rich nations of the developed world--are changing the planet so rapidly that we're entering a new geological age called the Anthropocene, one in which humans are dominant force on the global ecosystem. That puts a lot of responsibility on our shoulders to manage the planet, and as the Nature Conservancy's Rob McDonald put it with elegant understatement in a recent essay, "our track record of such management thus far is not encouraging."

So if tackling environmental problems globally seems impossible for now, what should we be doing? For one thing, Lomborg thinks, we should take some of the attention and money that goes to fight climate change and instead put it towards environmental threats that are killing people right now: namely, the lack of clean water and sanitation, as well as ordinary air pollution. Nearly a million people die annually due to outdoor air pollution from sources like coal-fired power plants and traffic fumes, while as many as 2 million people--nearly all in the developing world--die from indoor air pollution that mostly comes from cooking and heating in poorly ventilated huts. "We need to focus on those practical problems," Lomborg told me in a recent interview. "That's where a difference can be made now."

To those who fear that we might be standing on the brink of planetary collapse, concentrating on clean-burning stoves might seem like straightening the pictures while the house burns down. But if there's one lesson we can take from Rio, it's that top-down problem solving isn't an option any longer. Maybe the best we can do for now is try to solve the small problems--and hope that the big ones are less big than we fear.