Thursday, October 30, 2014

WSJ: "The gloves are off." Pathetic Steyer ad tries to sell climate scam with fake condom ban

Desperate, dirty-tricks climate-scam promoter & fossil-fuel-billionaire-hypocrite Tom Steyer buys ads falsely claiming a Republican will ban condoms, and tries to tie that absurd claim to climate change:

"That climate change enthusiasm deficit is not for [Steyer's] NextGen’s lack of trying. 
The committee has run slews of television ads blasting Republicans for “denying the science of climate change,” but it still hasn’t cracked the polls as a hotbed issue. Climate change doesn’t appear on Gallup’s monthly list of “most important problem” list, and even the more general “environment/pollution” category gets only 2 percent of the total. 
Perhaps as a result, even NextGen Climate isn’t focused solely on the climate. The committee also has sponsored commercials weighing in on standard Democratic Party talking points such as the Koch brothers and birth control aimed more at boosting Democrats than spreading the word on climate. 
For example, NextGen’s fingerprints are on a radio ad airing in the Senate race in Colorado that accuses Republican Rep. Cory Gardner of banning condoms. On Monday, NextGen contributed $239,000 to the NARAL Pro-Choice Colorado IE Committee, which then paid a consultant for the radio ad, according to The Federalist."

The Gloves Are Off

Condom shortages and other Democratic trouble signs


We’ve got to hand it to NARAL Pro-Choice America (née National Association for the Repeal of Abortion Laws), which has put out the funniest series of political ads at least since one Christine O’Donnell solemnly intoned to the camera: “I am not a witch.”

The NARAL spots—TV and radio—seek to influence the Colorado senate race, in which Republican Rep. Cory Gardner has been slightly favored to unseat Sen. Mark Udall. The incumbent has relied so heavily on the once-fashionable Democratic war-on-women shtick that he’s earned the derisive nickname “Mark Uterus.”

NARAL’s ads send mixed messages, which is to say that they jump around in an abrupt and madcap way between WOW and other themes. The radio spot begins with a conversation between a heterosexual couple. He has returned home to report failure in his mission to purchase condoms. “How did this happen?” she asks.

He replies: “Cory Gardner banned birth control, and now it’s all on us guys. And you can’t find a condom anywhere. And the pill was just the start. The Pell grants my little brother was counting on for college? Cory cut them! Climate change that everyone knows is weirding our weather—Cory flat-out denies it! Sweet pea, Cory denies science!”

Some guys just know how to talk to the ladies.

The TV ad seems to be directed at the gents. It’s divided into two parts, each introduced by a narrator with a high-pitched voice, one of each sex, frantically addressing the viewer as “Guysguysguysguysguys.” The second part is variation on the contraception theme: “If Cory Gardner gets his way, you better stock up on condoms.” The first part claims Gardner “denies climate change” and shows cars being swept away by rising seas.

Guysguysguysguysguys, Colorado is a doubly landlocked state whose lowest point is 3,310 feet above sea level.

The ads’ claims about Gardner are false. An anti-Gardner site quotes the congressman as acknowledging climate change: “I think the climate is changing, but I don’t believe humans are causing that change to the extent that’s been in the news.” As for the assertion that Gardner seeks to ban birth control, that would be true only if “ban” meant “to make available without a prescription.”

We guess the rationale here is to hope either that the massive quantity of arguments will compensate for their poor quality, or that their scattershot variety will somehow yield a broad appeal across liberal constituencies. Maybe they even have some nonliberal constituencies in mind. We were scratching our head wondering why they would make the small concession to reality of acknowledging that Gardner doesn’t want to ban condoms. Then it occurred to us that maybe they imagine there are extremists who do, and are trying to depress turnout.

also today:

Outside Groups Spending Huge Money On Colorado Senate Race

"But Udall supporters are doubling down on the message, with NARAL Pro-Choice Colorado releasing an ad this week warning that if Gardner is elected, it will lead to a shortage of condoms because he will have banned other forms of birth control. (Gardner actually advocates the sale of birth control pills over the counter.)
Media outlets are having a hard time reporting on the new ad with a straight face. 
"National Review mocked it twice, once in a straight news story titled “Udall Going All In on What Hasn’t Been Working” and again in a mock send-up blaming Gardner for banning everything from bread to Ramen noodles — “anything that could hurt an unborn child.”

New paper claims 'evidence of human influence first emerges from sea level rather than temperature'

A new paper and editorial in Nature Climate Change finds 
"natural variability complicates the detection of anthropogenic climate change in the twenty-first century. Now, research shows that evidence of human influence first emerges from sea level rather than temperature rise."
This is a curious move of the goalposts, since the IPCC claims a bogus 95% confidence that "most" of the warming since 1950 is anthropogenic on the basis of temperature rise since 1950, not on the basis of sea level rise, and thus opposite to the claims of this new paper. In addition, this new paper claims climate models predict allegedly anthropogenic "sea level rise signals can arise as early as 2020 over half the global ocean regions."

If that's the case, there's a lot of sea level rise catching up to do, since global sea levels have been naturally rising for ~20,000 years and have decelerated over the past 8,000 years, decelerated over the 20th century, decelerated 31% since 2002 and decelerated 44% since 2004 to less than 7 inches per century. There is no evidence of an acceleration of sea level rise, and therefore no evidence of any effect of mankind on sea levels. Sea level rise is primarily a local phenomenon related to land subsidence, not CO2 levels.

Further, observational data shows 86%-93% of the alleged AGW "missing heat" is still missing and not in the oceans or atmosphere, and missing or non-existent heat cannot cause sea level rise.

In addition, a paper published today in the Journal of Atmospheric and Oceanic Technology finds that the long-term ocean heat content trend is less than previously believed due to sampling biases. The authors "concluded that Argo-period climatologies [only available since 2004] should be used to accurately assess the long-term trend of the climate indicators such as OHC [ocean heat content]."

And what do ARGO-period ocean heat observations show? A tiny increase in ocean heat content, or even a decrease of ocean heat content [before Josh Willis "corrected the ocean cooling" by throwing away the ARGO float data he thought was too cold]

ARGO data before "correction" to remove cooling

Even with the biased and artificially warmed long-term ocean heat content data, the record only shows a very tiny 0.09C ocean warming over the past 55 years.

Thus, sea level rise and ocean heat content have "paused" right along with the "pause" in global surface temperatures. It will likely be many years [if ever] before a clear "signal" of anthropogenic global warming is detected in sea level rise acceleration, ocean heat content acceleration, surface temperature rise, or a tropospheric "hot spot," all of which still remain missing in the 21st century.

Excerpt from Nature Climate Change:

Time of emergence for regional sea-level change

Nature Climate Change
Published online
Determining the time when the climate change signal from increasing greenhouse gases exceeds and thus emerges from natural climate variability (referred to as the time of emergence, ToE) is an important climate change issue1. Previous ToE studies were mainly focused on atmospheric variables234567. Here, based on three regional sea-level projection products available to 2100, which have increasing complexity in terms of included processes, we estimate the ToE for sea-level changes relative to the reference period 1986–2005. The dynamic sea level derived from ocean density and circulation changes alone leads to emergence over only limited regions. By adding the global-ocean thermal expansion effect, 50% of the ocean area will show emergence with rising sea level by the early-to-middle 2040s. Including additional contributions from land ice mass loss, land water storage change and glacial isostatic adjustment generally enhances the signal of regional sea-level rise (except in some regions with decreasing total sea levels), which leads to emergence over more than 50% of the ocean area by 2020. The ToE [time of emergence of an anthropogenic "signal"] for total sea level is substantially earlier than that for surface air temperature and exhibits little dependence on the emission scenarios, which means that our society will face detectable sea-level change and its potential impacts earlier than surface air warming.

Wednesday, October 29, 2014

New paper finds sunshine has controlled maximum temperatures and temperature ranges in China since 1962

A paper published today in the Journal of Geophysical Research Atmospheres finds that daily [diurnal] temperature range in China decreased from 1962 to 2011, and that this decrease was due to a decrease in maximum temperatures related to a decrease of sunshine durations over this period. 

These changes are indicative that sunshine durations, rather than increased greenhouse gases, were the "control knob" which decreased maximum temperatures and decreased daily temperature ranges throughout China, and opposite of the predictions of AGW theory and climate models. 

The authors examined 479 weather stations in China from 1962-2011 and find 
"Results showed that DTR [daily temperature range] decreased rapidly (0.291 C/decade) from 1962 to 1989 due to slightly decreased Tmax [maximum temperatures] and significantly increased Tmin [minimum temperatures], but the decrease in DTR [daily temperature range] has stopped since 1990 as Tmax [maximum temperatures] and Tmin  [minimum temperatures] kept pace with each otherDuring 1990-2011, DTR [daily temperature range] remained trendless, with slight increase in the 1990s and slight decrease after 2000. During the whole study period from 1962 to 2011, DTR [daily temperature range] decreased at a rate of 0.157 C/decade nationally."
"Seasonally, DTR [daily temperature range] decreases were greatest in winter and lowest in summer, and the magnitudes of decrease reduced from the north to south of China. 
"The changes in DTR [daily temperature range] were closely correlated with changes in sunshine duration (SD) in China except the Tibetan Plateau, suggesting that SD [sunshine duration] decrease is an important contributor to the decrease of DTR [daily temperature range] through its influence on Tmax [maximum temperatures]."
In addition, the authors find that "the most arid region of China" experienced "increasing of precipitation," the opposite of the debunked CAGW meme of "dry gets drier and wet gets wetter." 
"In addition to the contribution of SD [sunshine duration] decrease, the increasing of precipitation played an important role in DTR [daily temperature range] decrease in Northwest China, the most arid region of China."
Similar to the findings of this paper, examination of the raw global temperature data [prior to tampering] shows a significant increase in minimum temperatures over the period 1962-1989, and then leveling off 1989-present. However, over the entire period 1940-present, there is no trend in minimum, maximum, or average global temperature anomalies. 

Spatiotemporal change of diurnal temperature range and its relationship with sunshine duration and precipitation in China

Xiangjin Shen et al

We examined the spatiotemporal variation in diurnal temperature range (DTR) and discussed the reasons for the changes of DTR in China based on data from 479 weather stations from 1962 to 2011. Results showed that DTR decreased rapidly (0.291 C/decade) from 1962 to 1989 due to slightly decreased Tmax and significantly increased Tmin, but the decrease in DTR has stopped since 1990 as Tmax and Tmin kept pace with each other. During 1990-2011, DTR remained trendless, with slight increase in the 1990s and slight decrease after 2000. During the whole study period from 1962 to 2011, DTR decreased at a rate of 0.157 C/decade nationally. Spatially, decreases in DTR were greatest in Northeast China and lowest in Southwest China with a transect running from northeast to southwest showing the decreasing trends change from high to low. Seasonally, DTR decreases were greatest in winter and lowest in summer, and the magnitudes of decrease reduced from the north to south of China. The changes in DTR were closely correlated with changes in sunshine duration (SD) in China except the Tibetan Plateau, suggesting that SD decrease is an important contributor to the decrease of DTR through its influence on Tmax. In addition to the contribution of SD decrease, the increasing of precipitation played an important role in DTR decrease in Northwest China, the most arid region of China. It appeared that changes of cloud cover (CC) were not the reasons for DTR changes in the past 50 years as CC has decreased during the study period.

White House sued about claims that man-made global warming caused polar vortex and record-cold winter

Excerpt from The Daily Caller:

Lawsuit: White House Won’t Show Evidence To Back Up ‘Polar Vortex’ Claims

A free-market think tank is suing the White House Office of Science and Technology Policy over its withholding of documents linked to the claim that global warming caused last winter’s polar vortex.
The free-market Competitive Enterprise Institute filed a lawsuit on Wednesday demanding documents related to the White House’s polar vortex video. The suit comes after CEI previously petitioned the White House to correct the video, which was criticized by climate scientists and ran counter to peer-reviewed studies.
But the White House said the video, in which White House science czar John Holdren connected global warming to the harsh winter, was based on Holdren’s “personal opinion” and exempt from data quality laws. When CEI tried to obtain federal documents related to the video, officials said they were part of the “deliberative process” and exempt from records requests.
“If this video really represented Dr. Holdren’s personal opinion, then it’s bad enough that OSTP spent taxpayer dollars to produce and post it on the White House web site,” said CEI general counsel Sam Kazman. “But for the agency to refuse to disclose documents related to the video in order to protect what it claims are internal deliberations is doubly ridiculous.”
The White House released its polar vortex video last January. In the video, Holdren claimed a “growing body of evidence suggests that the kind of extreme cold being experienced by much of the United States as we speak is a pattern that we can expect to see with increasing frequency as global warming continues.”
The idea is that melting Arctic ice sheets weakens the swirling mass of cold air in the polar region, called the polar vortex. As the vortex weakens, its pattern becomes more erratic and pushes cold air farther south. But the video was quickly debunked by climate scientists and peer-reviewed studies showing the polar vortex is not a product of global warming (or climate change, or whatever).
“While perhaps it could be argued that Holdren’s statement is not an outright lie, it is, at its very best, a half-truth and even a stretch at that,” wrote scientists Pat Michaels and Chip Knappenberger with the libertarian Cato Institute. “For in fact, there is a larger and faster growing body of evidence that directly disputes Holdren’s contention.”
“It’s an interesting idea, but alternative observational analyses and simulations with climate models have not confirmed the hypothesis, and we do not view the theoretical arguments underlying it as compelling,” five top climate scientists wrote in a letter published in Science Magazine in the wake of Holdren’s claims.
Studies done before Holdren’s claim that global warming is causing frigid winters also cast doubt on the integrity of the White House polar vortex video.
Research by Colorado State University’s Elizabeth Barnes in 2013 found that claims that “amplified polar warming has led to the increased occurrence of slow-moving weather patterns and blocking episodes, is unsupported by the observations.”
A study published before Barnes’s by Australian scientists James Screen and Jan Simmonds found that statistically significant changes in the jet stream depended largely on the methodology used by scientists. Screen and Simmonds noted their findings have “different and complex possible implications for midlatitude weather, and we encourage further work to better understand these.”
A recent study from Japanese scientists, however, claims that melting Arctic ice will bring colder winter with it. The study found that severe winters happening in Europe and Asia have doubled due to melting ice sheets.
Despite the conflicting evidence on the Arctic’s role in cold winters, the White House has not backed off from its claims that global warming is driving frigid weather. Even though Holdren purportedly espoused his opinion in the video, that has not been disclosed nor has the video been changed.
“Perhaps OSTP should give us a new video titled ‘The Holdren Document Vortex Explained in 2 Hours,’” Kazman quipped.

Observational data shows 86% of the "missing heat" is still missing and not in the oceans or atmosphere

In a comment on the Kiwi Thinker post yesterday, Bill Illis debunks the warmist's claim that "90% of the 'missing heat' allegedly trapped by greenhouse gases has gone into the oceans. Bill shows the numbers simply do not add up, 86% of the "missing" energy is still missing and has left to space, or is still hiding somewhere outside of the oceans and atmosphere [highly unlikely]. 

In addition, for multiple physical reasons, IR radiation from greenhouse gases cannot heat the oceans, due to a penetration depth of only a few millionths of one meter, which causes evaporative cooling of the ocean "skin" surface, not warming. Also, decreasing the temperature gradient between the ocean and atmosphere by a doubling of CO2 levels could only warm the oceans by 0.002C at most. And since there has been ~zero warming of the atmosphere for the past 16-26 years, there has been zero change in the ocean-atmosphere temperature gradient over that period. 

Therefore, we can effectively show no significant anthropogenic warming has gone into the oceans over the past 16-26 years due to no change in the gradient, that the ocean temperature changes have been related to solar (mediated by clouds and other potential amplification mechanisms), and to natural ocean oscillations, but not to increases in man-made CO2.

Skeptical Science tells you that 90% of the warming went into the oceans. That is, of the heat remaining in the system, 90% went into the oceans.
But they really left out the percentage that has merely been emitted back to space and/or is simply missing.
The IPCC says that the net forcing is +2.30 W/m2 right now. On top of that, there should have been water vapor and cloud feedbacks for another +1.75 W/m2.
But all that is showing up is 0.535 W/m2. 86% of the energy is no longer here or is missing.
The latest numbers from CERES shows that there is no change in Net Radiation since the year 2000, almost 14 years now.

Updated CERES numbers to April 2014.

Tuesday, October 28, 2014

New paper finds El Ninos were more common during Little Ice Age, opposite of climate alarmist claims

A paper published today in Geophysical Research Letters finds that El Ninos were more common during the frigid Little Ice Age, and conversely, La Ninas were more common during the Medieval and Roman Warm Periods. This finding is the opposite to claims by the IPCC and climate alarmists such as Kevin Trenberth that global warming, if it resumes, will make El Ninos more frequent.

The paper joins others debunking the claim that El Ninos have become more common during the 20th century, or that global warming increases the frequency or strength of El Ninos. 

Upwelling variability off southern Indonesia over the past two millennia

Stephan Steinke et al

Modern variability in upwelling off southern Indonesia is strongly controlled by the Australian-Indonesian monsoon and the El Niño-Southern Oscillation, but multi-decadal to centennial-scale variations are less clear. We present high-resolution records of upper water column temperature, thermal gradient and relative abundances of mixed layer- and thermocline-dwelling planktonic foraminiferal species off southern Indonesia for the past two millennia that we use as proxies for upwelling variability. We find that upwelling was generally strong during the Little Ice Age (LIA) and weak during the Medieval Warm Period (MWP) and the Roman Warm Period (RWP). Upwelling is significantly anti-correlated to East Asian summer monsoonal rainfall and the zonal equatorial Pacific temperature gradient. We suggest that changes in the background state of the tropical Pacific may have substantially contributed to the centennial-scale upwelling trends observed in our records. Our results implicate the prevalence of an El Niño-like mean state during the LIA [Little Ice Age] and a La Niña–like mean state during the MWP [Medieval Warm Period] and the RWP [Roman Warm Period].

Related: New paper debunks claim that greenhouse gases make climate "more El Niño-like"

New paper finds very low climate sensitivity to doubled CO2 levels of less than 0.3C

A new paper calculates the climate sensitivity to greenhouse gases by using seasonal changes to determine the climate response to radiative forcing from the Sun, and then uses the IPCC radiative forcing assumptions of solar forcing and greenhouse forcing to determine sensitivity to CO2. 

According to the analysis, the climate sensitivity to doubled CO2 is only 0.23C to 0.32C [mean 0.275C], an order of magnitude less than claimed by the IPCC, but right in line with 15 other papers and analyses finding very low climate sensitivity to CO2 of << 1C for a doubling of CO2 levels. 

Note the 0.23C sensitivity calculation assumes 1 W/m2 of solar forcing has the same effect as 1 W/m2 greenhouse forcing [as assumed by the IPCC], whereas the 0.32C sensitivity calculation assumes solar forcing has a greater effect on climate than greenhouse forcing [as claimed by other papers, due to energetic UV from the Sun only, which can penetrate the oceans unlike IR from greenhouse gases, and potential solar amplification mechanisms].

The author finds sensitivity to doubled CO2 is ~0.5C in the Northern Hemisphere and ~0.2 in the Southern Hemisphere, and that the oceans [more of which are in the Southern Hemisphere] act as a strong negative-feedback cooling agent for the global climate.

Google translation from the summary of the paper at the Swedish Stockholm Initiative site, and link to the full paper [in English], which is currently under open review:

Open examination

I have long wondered if it would be possible to use the seasons to appreciate the earth's sensitivity to greenhouse gases. On a beautiful day, I took hold of the matter and wrote a paper. After that I got good feedback from some other climate educators and updated the paper here [in English]
But it felt like it was too easy to get this together. It's very simple calculations done, so someone ought to have thought like this before. But I have not seen any such calculations here before. Therefore do I now up this report here at KU as a kind of "open review".
I would first like to have views on whether there is any reason why you could not count on it this way. Then I would like to have comments on whether the report is understandable and if there are unclear parts. 
The report is in English, but below is a brief summary in Swedish. [Google translation]
Using seasonal changes to appreciate Earth's reaction to radiation effects
Nature performs a continuous experiment with altering the Earth's radiation balance. During the northern hemisphere winter gets more Southern Hemisphere insolation and during the summer, the northern hemisphere more solar radiation. If we consider the northern and southern hemisphere as energetically relatively isolated from each other, we can follow the changes in solar radiation produces a change in temperature. Below are averages for the years 1979-2013 from ECMWF. Note that "irradiance" means "radiation per surface".
Temperature and solar radiation (scaled down to 1 / 10th) of the Northern Hemisphere
Temperature and solar radiation (scaled down to 1 / 10th) of the Southern Hemisphere
One can clearly see that the temperature is a little behind insolation on time. It is probably due to a sluggish response especially from the time it takes to warm up lakes and seas. Therefore, it is faster to heat up than the land masses of the oceans. But the system still responds fairly quickly to changes. The maximum temperature is reached after only one month after maximum insolation reached.
It is also clear that the northern hemisphere and the southern hemisphere is about the same inertia, but that the temperature changes much less in the southern hemisphere. This suggests that there is a strong negative feedback in the Southern Hemisphere.
Based on these measured data, I try now to create a climate model with approximately the same temperature response to a change in solar radiation. If we assume that the temperature response is a function of solar radiation, but that the temperature response is also low pass filtered to obtain an inertia, the climate model can be described as follows:

Flow chart for simple climate model.
ΔI is the change in radiation (irradiance), and Dt is the change in temperature.
To adapt this climate model against measured values ​​are needed only three parameters:
the first A temperature shift to be able to convert between delta temperatures to absolute temperatures of
the second A slope factor between insolation and temperature (parameter ki picture above).
3rd A filter value to define the inertia of the system.
By adjusting these three values ​​for the northern hemisphere and the southern hemisphere, I try to get a good consistency with the measured values ​​as possible. The result is shown below.
Solar radiation, temperature and simulated temperature for the Northern Hemisphere
Solar radiation, temperature and simulated temperatures for the southern hemisphere.
It is clear that it is possible to obtain a very good agreement between measured values ​​and model.
According to the IPCC, a doubling of carbon dioxide levels result in increased radiation of about 3.7W / m² and that this would correspond to about 5.1W / m² increase in solar radiation. Therefore, we can use the simple climate model described above to calculate how much higher temperature 5.1W / m² would provide.
The result is that the so-called climate sensitivity, ie a doubling of carbon dioxide, would provide approximately 0.5 ° C in the northern hemisphere and 0.2 ° C in the southern hemisphere. But this calculation does have its uncertainties. The greatest uncertainty is: if there is a (unknown to me) significant energy flow between the hemispheres, which is seasonal, the Earth's albedo changes with solvinkeln, and on the assumption that 3.7W / m² carbon radiation corresponding to 5.1W / m² solar radiation would be wrong. The first uncertainty can increase the climate sensitivity figure, and the other two can potentially lower the climate sensitivity figure is significant.
Excerpts from the paper:
Magnus Cederlöf   Version 0.4   October 18, 2014
By looking at how the changed solar radiation over the annual seasons a ect the two hemispheres it is possible to get an estimation of how the climate system reacts to changes in the radiation balance. The inertia in both northern hemisphere (NH) and southern hemisphere (SH) is about the same, but the temperature change in response to radiation change is much larger in NH than in SH. This implies a large negative feedback in the SH. Based on daily temperature data from ECMWF, a climate model with only three parameters is created. It is shown that this model can simulate the temperature response to the changes in solar irradiance (radiation per area) fairly well. If it is assumed that the energy exchange between NH and SH can be neglected, it is possible to calculate how the hemispheres react to changes in radiation forcing. If IPCC's assumption of forcing effi cacy is used, a 3.7W/m2 of greenhouse gas forcing, that is the climate sensitivity, should correspond to about 5.1W/m2 of solar forcing. This model show that 5.1W/m2 of radiation forcing would give approximately 0.5°C higher temperatures on the NH and approximately 0.2°C on the SH.
1 Introduction
Understanding how earth responds to a change in incoming radiation from the sun is essential to understanding how earth will react to increase level of so called greenhouse gases. This study uses the fact that nature conducts a continuous experiment in changing earth's radiation balance. During the northern hemisphere (NH) winter, southern hemisphere (SH) receives increased solar radiation, and vice versa. 
In this experiment I have used an average of the 2 meter temperature from ECMWF's ERA-interim reanalysis [1] which provides, amongst others, daily gridded temperature data for complete earth starting at 1979. This temperature is compared to the change in solar irradiance (radiation per area) to the two hemispheres. I have assumed that the solar irradiance is in average 338 W/m2 and that albedo is 0.3. This means that the average energy in ow on earth is in average 338*0.7=237 W/m2.
...4 Conclusion
Since both hemispheres show similar inertia but large di erences in temperature response compared to irradiance change, it implies that SH has a large negative feedback when the temperature changes. Similar pattern is seen in the difference between ocean and land in NH, where the ocean seems to have a large negative feedback. Therefore, it is reasonable to conclude that rising temperatures over water causes more clouds to form which will hold the temperature change back.
A very simple climate model with only three parameters can simulate the hemispheres temperature response to the seasonal changes in solar irradiance fairly well. By using this climate model, it is possible to estimate the hemispheres temperature response to increased radiative forcing from greenhouse gases. When assuming that the seasonal energy exchange between the hemispheres is neglectable and a doubling of the carbon dioxide level would cause 3.7W/m2 forcing, a climate sensitivity gure can be calculated. This climate sensitivity has in this case been calculated to about 0.5°C for NH and about 0.2°C for the SH if IPCC's assumptions of efficacy is used. In this case it is assumed that 3.7W/m2 of greenhouse forcing corresponds to 5.1W/m2 of solar forcing. But if the efficacy of greenhouse gases is signi cantly lower as at least one study indicates [4], the climate sensitivity will also be signi cantly lower. 
The major uncertainty factors in this study are: ˆ
  • If there is a (to me unknown) seasonal energy exchange between the hemispheres. ˆ 
  • If the efficacy comparison between greenhouse gases and solar radiation is incorrect. ˆ
  • If the albedo is sensitive to solar declination. 

The 1st factor, if found signi cant, will increase the climate sensitivity figure, but the other two can signi cantly decrease the climate sensitivity figure.
The strong negative feedback over the oceans can also explain why the biggest temperature rise during the 20th century occurred on land. But the temperature increase that has been measured is bigger than what would be expected due to the changes in the carbon dioxide levels according to this study. Therefore it is reasonable to assume that natural variations also causes the radiation balance to change and also in this case the land will experience the biggest temperature change.


Observations show IPCC exaggerates anthropogenic global warming by a factor of 7