Thursday, March 08, 2007

HAS SOLAR VARIABILITY CAUSED CLIMATE CHANGE THAT AFFECTED HUMAN CULTURE?

(Paper from Advances in Space Research)

Abstract

If solar variability affects human culture it most likely does so by changing the climate in which the culture operates. Variations in the solar radiative input to the Earth's atmosphere have often been suggested as a cause of such climate change on time scales from decades to tens of millennia. In the last 20 years there has been enormous progress in our knowledge of the many fields of research that impinge on this problem; the history of the solar output, the effect of solar variability on the Earth's mean climate and its regional patterns, the history of the Earth's climate and the history of mankind and human culture. This new knowledge encourages revisiting the question asked in the title of this talk.

Several important historical events have been reliably related to climate change including the Little Ice Age in Northern Europe and the collapse of the Classical Mayan civilization in the 9th century AD. In the first section of this paper we discus these historical events and review the evidence that they were caused by changes in the solar output.

Perhaps the most important event in the history of mankind was the development of agricultural societies. This began to occur almost 12,000 years ago when the climate changed from the Pleistocene to the modern climate of the Holocene. In the second section of the paper we will discuss the suggestion that climate variability was the reason agriculture developed when it did and not before.

1. Introduction

Three types of information need to be compared to address the subject assigned to me by the organizers of this conference, the history of the Sun, the history of climate, and the history of human culture. All of these fields are now going through a "Golden Period" of development, and studies of the connections between them are in their infancy. The pictures of their interconnections can now only be drawn with broad strokes. In this paper we are interested in effects of climate change on human life, in particular the effects of a variable Sun.

Modern man developed in East Africa about 130,000 years ago and spread to the rest of the world beginning sometime about 55,000 years ago. We will not be concerned with any solar changes that took place before the exit from Africa. A major source for the radiative history of the Sun comes from radioactive 14C and 10Be produced by cosmic rays interacting with the atmosphere (Beer et al., 1994). The intergalactic cosmic rays reach the Earth after having been modulated by the solar wind. In general, the faster the solar wind and the larger its magnetic field, the lower the change in radiocarbon 14C (Stuiver & Braziunas, 1988).

The history of 14C for the last 1,200 years is illustrated in Figure 1 taken from the cited paper. Higher 14C indicates a less active Sun. For an estimate of the history of solar activity for the last 11,000 years see Solanki et al. (2004). Information on past climates is available from historical records and can also be found by the study of the records of the Earth's climate imprinted in a variety of climate proxies. Perhaps the best known of these "data banks" are the polar ice cores from Greenland. These ice cores contain proxy records of diverse climate variables. For example, the oxygen isotopes in snow characterize temperatures (Grootes & Stuiver, 1997; Cuffey & Clow, 1997), while sea salt blown from the ocean reflect atmospheric winds. The records from the Greenland Ice Sheet Project 2 (GISP2) (Mayewski et al., 1997) have been analyzed extensively to describe past climate (Meeker et al., 1997). A large number of other Climate Proxy Records (CPR) of various types have been collected from wide spread regions of the globe. Examples of CPR include ice cores from the Antarctica and high-altitude mountain glaciers, and sea sediment cores (Peterson et al., 2000). Many CPR have been intercalibrated to obtain well-dated records of tracers of worldwide climate change (De Angelis et al., 1997; Hughen et al., 2000).

There are now many empirical and modeling studies that demonstrate that changes in the solar output are associated with widespread changes in climate (Lean & Rind, 2001) and climate patterns (Ruzmaikin et al., 2004). The development of quantitative models and a physical understanding of all the underlying mechanisms involved is currently a rapidly developing field of study. Information on human cultures come from historical and archeological studies and studies of the genetics of humans, animals and plants.

[...]

4. Discussion

In section 2 we showed two examples of the stresses that relatively small climate variability presented for well-established cultures. In these cases evidence was given that the variations were part of a worldwide response pattern and that they were associated with the Sun. In section 3 we demonstrated that there were very large continuous climate variations throughout the Pleistocene. From the Holocene experience we can speculate these changes must surely have interfered with early domestication where they occurred. In both Greenland and the Caribbean our data show that the changes continued throughout the glacial and interglacial periods before the Holocene. They also occurred in both the Greenland ice sheets and the ice-free Caribbean.

We also know that temperatures are now organized in hemisphere-wide strongly correlated patterns (Quadrelli & Wallace, 2004). Climate modeling shows that although there were differences in the glacial and interglacial patterns, in both those periods large strongly correlated patterns existed (Toracinta et al., 2004). It is therefore not such a stretch of the imagination to hypothesize that the rapid variations in temperature seen in Greenland and the Caribbean were part of such patterns.

There is less evidence that they were solar driven during the Pleistocene, but apparently smaller climate variations were solar driven during the Holocene, and the Sun must also have varied in the same manner during the Pleistocene.

In summary there is considerable evidence that climate variations in response to low frequency solar variations have had major effects on cultures during the last fifteen hundred years. We also hypothesize that the large climate variations in the same frequency range may have had a role in inhibiting the development of agriculture during the Pleistocene and it was their marked decrease in amplitude that allowed agriculture to develop independently almost simultaneously in multiple regions of the world when the Holocene began at the end of the YD.

(The Doi (permanent) address for the full article above is here)




SPACE CLIMATE AND THE SOLAR-STELLAR CONNECTION

(Paper from Advances in Space Research)

Abstract

While it is well-known that solar variability influences the near-Earth Space environment at short timescales of days -- an effect collectively termed as SpaceWeather, a more subtle influence of solar variability at longer timescales is also present and just beginning to be appreciated. Long-term solar forcing and its consequences -- which has come to be known as Space Climate -- has important consequences for the formation and evolution of planetary atmospheres, the evolution of life and global climate on Earth.

Understanding the Sun's variability and its heliospheric influence at such scales, stretching from decennia to stellar and planetary evolutionary timescales, is therefore of fundamental importance. However, our knowledge of this variability, which is in part due to the evolution of the solar magnetic dynamo, is limited by direct solar observations which exist only from early 17th Century onwards.

In this review we introduce a novel concept -- how the Solar-Stellar connection can be exploited to understand the long-term variability of the Sun and its influence on Space Climate. We present some preliminary studies, in which, through theoretical dynamo modeling and analysis of magnetic activity observations of solar-like stars at various evolutionary phases relative to the Sun, we show how the above concept is implemented in practice.

[...]

5. Concluding Remarks

Here we have outlined a novel concept -- utilizing the solar-stellar connection to decipher long-term solar variability. We have also presented preliminary results from the "Stars as Suns" project to demonstrate how this concept can be implemented in practice. Our focus is to illuminate the relatively unexplored role played by solar forcing in shaping planetary climate and habitat by uncovering the long-term evolution of the Sun's activity.

In our studies we are exploring the Solar-Stellar connection; there is much to be learned from the stars. On the one hand we are studying the theoretical aspects of solar and stellar magnetic field generation and its evolution with stellar age through dynamo modeling. On the other hand, we are complementing this by observational analysis of stellar luminosity and magnetic activity data. This dataset is not complete, and indeed sparse, but work is ongoing to supplement it. In this context, a targeted space mission to study the magnetic activity in various wavelengths of a wide sample of solar-like stars would be extremely timely. Our studies also need to be supplemented by detailed numerical MHD modelling of stellar evolution and the variation of stellar processes such as differential rotation and meridional circulation (that have implications for the dynamo mechanism) with stellar age; such efforts are just beginning (Allan Sacha Brun, private communication).

The wider implication of the evolution of the solar dynamo mechanism in the context of Space Climate research has become evident in recent times and so have the scope and relevance of the "Stars as Suns" project become substantially larger and important. Beyond its connection with just the global temperature as suggested by the climatological record, the changing Sun and its changing radiation over the past billions of years must have played a crucial role in the modulation of the climate system of the "young" Earth and in the evolution of primitive life-forms in planetary atmospheres. For example, the "young" Sun's higher EUV radiation or lower luminosity could have affected the synthesis of amino acids and nucleic acids; thus a quantitative estimate of the early Earth's radiation environment is crucial for discriminating between competing theories for the origin of life, e.g., the cold incubator versus the hot primordial soup (John Priscu, private communication). Conversely, solar radiation could have played a negative role in the destruction of life-forms on planets lacking a protective magnetosphere. Looking ahead, for long term planning of the future direction of humans and other living organisms on Earth and associated technologies, one needs to have an idea of how solar activity will change in the distant future. Indeed, the stakes for unravelling long-term solar variability and its impact on Space Climate are high.

(The Doi (permanent) address for the full article above is here)






EU INDUSTRY COMMISSIONER WARNS AGAINST CLIMATE 'HYSTERIA'

Global warming belief is beginning to go where the money dictates. And money is where the EU is hurting

EU industry commissioner Guenter Verheugen has warned against hysteria in the climate change debate as the bloc considers setting stringent new caps for greenhouse gas emissions at a summit later this week. Sounding a dissonant note amid calls to make the EU a global leader in emissions cutting over the coming decade, Mr Verheugen told Germany's Bild am Sonntag that while climate change ought to be fought on all fronts, the EU "should not descend into hysterical action."

The German commissioner also went on to speak about "strange trends" in public debate saying "two years ago, it was all 'jobs, jobs, jobs' now it's 'climate, climate, climate.'" He reiterated his fear - expressed most recently at EU plans to get the car industry to make cars that pollute less - that by trying to raise the environment bar within the EU, the bloc risks losing out on competitiveness to other, less green, regions in the world. "Our most important task will be to make sure that the US, China, India and Russia are just as engaged in climate protection as we are."

Mr Verheugen's words capture the current political struggle within the EU on how to reconcile being green with being competitive. This division is likely to be played out at a meeting of EU leaders on Thursday and Friday as they meet and debate whether to set binding targets for carbon dioxide emission reduction and reliance on renewable energy. The European Commission, headed by Jose Manuel Barroso - a recent convert to the economic arguments for fighting climate change - is pushing for concrete targets, fearing that vague commitments will undermine the EU's environment rhetoric.

Last week, the current head of the EU, German chancellor Angela Merkel, said the EU must demonstrate that it is possible to be both economically progressive and environmentally friendly and is set to push for ambitious targets in the summit's conclusions this week. German daily Handelsblatt reported on Monday that Berlin wants the EU to promote big long-term cuts by industrial nations in CO2 emissions - 60 to 80 percent by 2050 - and a 30 percent cut for the EU by 2020.

But although it will make for headlines around the world if the EU sets stringent long-term goals, the devil will remain in the detail with entrenched behind-the-scenes squabbling expected as governments barter over how much of the burden they should each carry. EU environment ministers agreed last month to a 20 percent emissions cut by 2020, but the bloc is already scrambling to meet its target of an 8 percent reduction in CO2 emissions agreed under the international Kyoto protocol.

Meanwhile, countries such as the UK, which lately has been promoting its green credentials, are also having problems. UK daily the Guardian reports that an independent scientific audit of the country's climate change policies has predicted that Britain will fall well below its target of a 30 percent reduction in carbon dioxide emissions by 2020.

Source





THE CARBON FOLLY

Global warming isn't the only debate that may be over. Governments and policymakers around the world also seem to have settled on a solution. "A responsible approach to solving this crisis," Al Gore said recently at New York University's Law School, would be "to authorize the trading of emissions ... globally." Emissions trading, also called carbon trading, is being expanded in the European Union and Japan. And in many places where it's yet to take hold, like Sacramento, Sydney and Beijing, politicians are embracing it.

Nicholas Stern, former chief economist of the World Bank and Europe's foremost political expert on global warming, predicts that the value of carbon credits in circulation, now about $28 billion, will climb to $40 billion by 2010. This should be great news for the environment, but many experts have their doubts. The notion that emissions trading is going to make a significant dent in global warming is deeply flawed, they say.

Current emissions-trading schemes have proved to be little more than a shell game, allowing polluters in the developed world to shift the burden of making cuts onto factories in the developing world. Too often factory owners use the additional profits banked from carbon credits to expand their dirty factories. Even more worrying, emissions trading may have set back the battle against climate change by diverting investment from renewable-energy technology, which arguably is essential to any long-term solution.

So far, the real winners in emissions trading have been polluting factory owners who can sell menial cuts for massive profits, and the brokers who pocket fees each time a company buys or sells the right to pollute.

FULL STORY here




Solar System Warming?

Post lifted from Strata Sphere

Global warming on Neptune’s moon Triton as well as Jupiter and Pluto, and now Mars has some scratching their heads over what could possibly be in common with the warming of all these planets.

In the meantime, some have noticed an interesting relationship between solar activity and temperature proxies via ice cores going back thousands of years:



I still don’t know. Could there be something in common with all the planets in our solar system that might cause them all to warm at the same time?


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Many people would like to be kind to others so Leftists exploit that with their nonsense about equality. Most people want a clean, green environment so Greenies exploit that by inventing all sorts of far-fetched threats to the environment. But for both, the real motive is generally to promote themselves as wiser and better than everyone else, truth regardless.

Global warming has taken the place of Communism as an absurdity that "liberals" will defend to the death regardless of the evidence showing its folly. Evidence never has mattered to real Leftists


For more postings from me, see TONGUE-TIED, EDUCATION WATCH, POLITICAL CORRECTNESS WATCH, FOOD & HEALTH SKEPTIC, GUN WATCH, SOCIALIZED MEDICINE, AUSTRALIAN POLITICS, DISSECTING LEFTISM, IMMIGRATION WATCH and EYE ON BRITAIN. My Home Pages are here or here or here. Email me (John Ray) here. For times when blogger.com is playing up, there are mirrors of this site here and here.

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