Sun's Role Research Articles

Understanding the perception of sunscreen utility in African Americans.

Dyschromia is a top diagnosis among African Americans (AA). Sunscreen is an essential part of its management, but AA have low sunscreen use. We sought to examine the perception of sunscreen utility in dyschromia and photoaging among patients who identify as AA or Black. This cross-sectional study recruited participants from the Case Western Reserve University Academic Dental Clinic. Participants completed an electronic survey that contained questions related to sunscreen use, knowledge of the sun's role in hyperpigmentation and photoaging, and whether sunscreen could be used for hyperpigmentation and photoaging. Of the 151 participants recruited, 63.6% (n = 96) were women and 36.4% (n = 57) were men. Consistent with previous reports, participants had lower sunscreen use (20.5%) than whites (43.5%). The majority of participants (80.1% and 58.3%, respectively) didn't attribute the sun to hyperpigmentation or photoaging. Participants with dark/brown spots were significantly more likely to not attribute the sun to hyperpigmentation than those without spots. (p = 0.003) Limitations for this study include its small sample size, recall and reporter bias, question misinterpretation, and lack of question neutrality. This study highlights the knowledge gap of a major contributing factor to dyschromia which in turn could be leading to their view of the decreased utility of sunscreen.

The Sun's role in decadal climate predictability in the North Atlantic

Abstract. Despite several studies on decadal-scale solar influence on climate, a systematic analysis of the Sun's contribution to decadal surface climate predictability is still missing. Here, we disentangle the solar-cycle-induced climate response from internal variability and from other external forcings such as greenhouse gases. We utilize two 10-member ensemble simulations with a state-of-the-art chemistry–climate model, to date a unique dataset in chemistry–climate modeling. Using these model simulations, we quantify the potential predictability related to the solar cycle and demonstrate that the detectability of the solar influence on surface climate depends on the magnitude of the solar cycle. Further, we show that a strong solar cycle forcing organizes and synchronizes the decadal-scale component of the North Atlantic Oscillation, the dominant mode of climate variability in the North Atlantic region.

Solar activity imprints in tree ring-data from northwestern Russia

The Sun's role in climate variability is now a subject of debates, especially in the context of understanding contribution of solar forcing to modern global warming. Besides, there are some evidences of the approaching new Grand Solar Minimum with Little Ice Age climatic conditions. This expectation is based on the occurrence of the extended solar minimum of 2006–2009. To investigate the possible Sun-climate connection the regional tree-ring chronology covering the period from 1445 to 2005 was analyzed. A total of 36 timber cores of pine Pinus sylvestris L. were sampled near the northern tree-line at Loparskaya station (68.6 N, 33.3 E), including the oldest living pine with more than 560 years of age. The data were processed using modern methods adopted in dendrochronology (cross-dating and standardization) with the help of COFECHA and ARSTAN programs. The analysis revealed significant cooling events, coinciding with the Spoerer (1400–1540), Maunder (1645–1715), Dalton (1790–1830), and Gleissberg (1880–1910) Grand Solar Minima. The application of MTM-spectrum and wavelet decomposition analysis identified the existence of the main cycles of solar activity (5.4, 11.7 and 22 years) in tree-ring width variations. As possible extraterrestrial forcings of climate change we consider here variations in solar irradiance and cosmic ray intensity modulated by the interplanetary magnetic field. As solar and cosmic ray activity indicators we used the annual sunspot number, geomagnetic aa index and Be^10 cosmogenic isotope records. To examine the relationship in time-frequency scale between tree-ring growth and solar activity, the cross wavelet transform and wavelet coherence analysis were applied to the time series. The wavelet coherence analysis identified that the 11 yr and 22 yr periodicities were clearly manifested in the all solar-tree rings connections during and around the Grand Minima of solar activity including the Maunder minimum, when, as is known, sunspots were practically absent. These results confirm the existence of solar activity effect on climate and tree growth above the Arctic Circle and are important for understanding the modern climatic processes.

Ipcc Underestimates the Sun's Role in Climate Change

For the understanding of current and future climate change it is a basic pre requisite to properly understand the mechanisms, which controlled climate change after the Last Ice Age. According to the IPCC 5th assessment report (in prep.) the Sun has not been a major driver of climate change during the post-Little Ice Age slow warming, and particularly not during the last 40 years. This statement requires critical review as the IPCC neglects strong paleo-climatologic evidence for the high sensitivity of the climate system to changes in solar activity. This high climate sensitivity is not alone due to variations in total solar irradiance-related direct solar forcing, but also due to additional, so-called indirect solar forcings. These include solar-related chemical-based UV irradiance-related variations in stratospheric temperatures and galactic cosmic ray-related changes in cloud cover and surface temperatures, as well as ocean oscillations, such as the Pacific Decadal Oscillation and the North Atlantic Oscillation that significant affect the climate. As it is still difficult to quantify the relative contribution of combined direct and indirect solar forcing and of increased atmospheric CO2 concentrations to the slow warming of the last 40 years, predictions about future global warming based exclusively on anthropogenic CO2 emission scenarios are premature. Nevertheless, the cyclical temperature increase of the 20th century coincided with the buildup and culmination of the Grand Solar Maximum that commenced in 1924 and ended in 2008. The anticipated phase of declining solar activity of the coming decades will be a welcome ‘natural laboratory’ to clarify and quantify the present and future role of solar variation in climate change.

Solar and volcanic fingerprints in tree-ring chronologies over the past 2000 years

The Sun is the main driver of Earth's climate, yet the Sun's role in forcing decadal-to-centennial climate variations has remained controversial, especially in the context of understanding contributions of natural climate forcings to continuing global warming. To properly address long-term fingerprints of solar forcing on climate, long-term, very high-resolution, globally distributed climate proxy records are necessary. In this study we compile and evaluate a near global collection of annually-resolved tree-ring-based climate proxies spanning the past two millennia. We statistically assess these records in both the time and frequency domains for solar forcing (i.e. Total Solar Irradiance; TSI) and climate variability with emphasis on centennial time scales. Analyses in the frequency domain indicate significant periodicities in the 208-year frequency band, corresponding to the DeVries cycle of solar activity. Additionally, results from Superposed Epoch Analysis (SEA) point toward a possible solar contribution in the temperature and precipitation series. However, solar-climate associations remain weak, with for example no clear linkage distinguishable in the southwestern United States drought records at centennial time scales. Other forcing factors, namely volcanic activity, appear to mask the solar signal in space and time. To investigate this hypothesis, we attempted to extract volcanic signals from the temperature proxies using a statistical modelling approach. Wavelet analysis of the volcanic contribution reveals significant periodicities near the DeVries frequency during the Little Ice Age (LIA). This remarkable and coincidental superposition of the signals makes it very difficult to separate volcanic and solar forcing during the LIA. Nevertheless, the “volcano free” temperature records show significant periodicities near the DeVries periodicity during the entire past 1500 years, further pointing to solar mechanisms and emphasising the need for solar related studies in the absence of strong multi-decadal volcanic forcing.

The Sun's Role in Regulating the Earth's Climate Dynamics

This paper introduces this thesis: The Sun-Earth system is electromagnetically, magneto-hydrodynamically and gravitationally coupled, dominated by significant non-linear, non-stationary interactions, which vary over time and throughout the three-dimensional structure of the Earth, its atmosphere and oceans. The essential elements of the Sun-Earth system are the solar dynamo, the heliosphere, the lunisolar tides, the Earth's inner and outer cores, mantle, crust, magnetosphere, oceans and atmosphere. The Sun-Earth system is non-ergodic (i.e. characterised by continuous change, complexity, disorder, improbability, spontaneity, connectivity and the unexpected). Climate dynamics, therefore, are non-ergodic, with highly variable climatological features at any one time. A theoretical framework for considering the role of the Sun in relation to the Earth's climate dynamics is outlined and ways in which the Sun affects climate reviewed. The forcing sources (independent variables) that influence climate processes (dependent variables) are analysed. This theoretical framework shows clearly the interaction effects between and amongst the two classes of variables. These seem to have the greatest effect on climate dynamics. Climate processes are interconnected and oscillating, yielding variable periodicities. Solar processes, especially when interacting, amplify or dampen these periodicities producing distinctive climatic cycles. As solar and climate processes are non-linear, non-stationary and non-ergodic, appropriate analytic methodologies are necessary to reveal satisfactorily solar/climate relationships.

Book Review: The Sun Kings: The Unexpected Tragedy of Richard Carrington and the Tale of How Modern Astronomy Began

Book Review: <i>The Sun Kings: The Unexpected Tragedy of Richard Carrington and the Tale of How Modern Astronomy Began</i>

Shortwave forcing of the Earth's climate: Modern and historical variations in the Sun's irradiance and the Earth's reflectance

Changes in the Earth's radiation budget are driven by changes in the balance between the thermal emission from the top of the atmosphere and the net sunlight absorbed. The shortwave radiation entering the climate system depends on the Sun's irradiance and the Earth's reflectance. Often, studies replace the net sunlight by proxy measures of solar irradiance, which is an oversimplification used in efforts to probe the Sun's role in past climate change. With new helioseismic data and new measures of the Earth's reflectance, we can usefully separate and constrain the relative roles of the net sunlight's two components, while probing the degree of their linkage. First, this is possible because helioseismic data provide the most precise measure ever of the solar cycle, which ultimately yields more profound physical limits on past irradiance variations. Since irradiance variations are apparently minimal, changes in the Earth's climate that seem to be associated with changes in the level of solar activity—the Maunder Minimum and the Little Ice age for example—would then seem to be due to terrestrial responses to more subtle changes in the Sun's spectrum of radiative output. This leads naturally to a linkage with terrestrial reflectance, the second component of the net sunlight, as the carrier of the terrestrial amplification of the Sun's varying output. Much progress has also been made in determining this difficult to measure, and not-so-well-known quantity. We review our understanding of these two closely linked, fundamental drivers of climate.

Reconstruction of solar total irradiance since 1700 from the surface magnetic flux

Context. Total solar irradiance changes by about 0.1% between solar activity maximum and minimum. Accurate measurements of this quantity are only available since 1978 and do not provide information on longer-term secular trends.Aims. In order to reliably evaluate the Sun's role in recent global climate change, longer time series are, however, needed. They can only be assessed with the help of suitable models.Methods. The total solar irradiance is reconstructed from the end of the Maunder minimum to the present based on variations of the surface distribution of the solar magnetic field. The latter is calculated from the historical record of the sunspot number using a simple but consistent physical model.Results. Our model successfully reproduces three independent data sets: total solar irradiance measurements available since 1978, total photospheric magnetic flux since 1974 and the open magnetic flux since 1868 empirically reconstructed using the geomagnetic aa -index. The model predicts an increase in the solar total irradiance since the Maunder minimum of Wm-2 .

Light's role in immunomodulation and medical therapy

Light's role in immunomodulation and medical therapy

Fostering the People's Livelihood: Chinese Political Thought between Empire and Nation

Students of modem Chinese history are often faced with the discrepancy between Chinese and Western perceptions of Sun Vat-sen (f~~1l1J, styled f~1:f=lW, 18661925). Both in the People's Republic of China (PRC) and the Republic of China (ROC), historians, and the public large, consider Sun the father of the modem Chinese nation (~x:, guofu) and still regard his writings-especially the Three People's Principle's (~ ~.±~, sanmin zhuyi): Nationalism (~1i~±~, minzu zhuyi), People's Rights (~fl±~, minquan zhuyi), and People's Livelihood (~ j::±~, minsheng zhuyi)-important for the ideological development of modem Chines~ politics. Western historians, on the other hand, generally tend to downplay Sun's role in the 1911 revolution (the revolution that led to the demise of the Qing Dynasty and of the imperial system as a whole) and in the establishment of the country's first republic. They mostly regard the Three Principles as fuzzy best (Pusey 1982, 356). Even one of the most supportive among the recent biographers of Sun, the French historian Marie-Claire Bergere, describes the Principles as at times strange, a hybrid hodgepodge, but above all incoherent(Bergere 1998, 353-354). As a result of this process of historical deconstruction, Western historians have generally concluded that the continued prominence of Sun Yat-sen's memory is the result of the Nationalist Party's (~~ Ii, Guomindang or GMD, the political party established by Sun after the fall of the empire) conscious mythologizing. Western scholars stress how the Party promoted a narrative of Sun as father of the new Chinese nation in the effort to bolster the legitimacy of its leadership over China's national destiny (Fitzgerald 1996). The significance of Sun Vat-sen in modem Chinese history, however, goes beyond Nationalist mythologizing. In part, it springs from Sun's ability to formulate new political tropes that broke with the late-Qing imperial discourse and set the foundation for a national mode of political thinking. It was especially in the Three People's Principles that Sun translated into effective new political language the main intellectual trends that swept China in the latenineteenth and early-twentieth centuries. If we refrain from approaching the Principles from a Western-centered and presentist perspective-which inevitably makes them appear awkward vis-a-vis Western political discourses with which we are more readily familiar-and, instead, take into consideration their intellectual backdrop and Sun's political goals, we discover that the Principles estab-

Fostering the People's Livelihood: Chinese Political Thought between Empire and Nation

6 TWENTIETH-CENTURY CHINA FOSTERING THE PEOPLE'S LIVELIHOOD: CHINESE POLITICAL THOUGHT BETWEEN EMPIRE AND NATION MARGHERIT A ZANASI, UNIVERSITY OF TEXAS AT AUSTIN Students of modem Chinese history are often faced with the discrepancy between Chinese and Western perceptions of Sun Vat-sen (f~~1l1J, styled f~1:f=lW, 18661925 ). Both in the People's Republic of China (PRC) and the Republic of China (ROC), historians, and the public at large, consider Sun the father of the modem Chinese nation (~x:, guofu) and still regard his writings-especially the Three People's Principle's (~ ~.±~, sanmin zhuyi): Nationalism (~1i~±~, minzu zhuyi), People's Rights (~fl±~, minquan zhuyi), and People's Livelihood (~ j::±~, minsheng zhuyi)-important for the ideological development of modem Chines~ politics. Western historians, on the other hand, generally tend to downplay Sun's role in the 1911 revolution (the revolution that led to the demise of the Qing Dynasty and of the imperial system as a whole) and in the establishment of the country's first republic. They mostly regard the Three Principles as "fuzzy" at best (Pusey 1982, 356). Even one of the most supportive among the recent biographers of Sun, the French historian Marie-Claire Bergere, describes the Principles as "at times strange," a "hybrid hodgepodge," but above all "incoherent "(Bergere 1998, 353-354). As a result of this process of historical deconstruction , Western historians have generally concluded that the continued prominence of Sun Yat-sen's memory is the result of the Nationalist Party's (~~ Ii, Guomindang or GMD, the political party established by Sun after the fall of the empire) conscious mythologizing. Western scholars stress how the Party promoted a narrative of Sun as father of the new Chinese nation in the effort to bolster the legitimacy of its leadership over China's "national" destiny (Fitzgerald 1996). The significance of Sun Vat-sen in modem Chinese history, however, goes beyond Nationalist mythologizing. In part, it springs from Sun's ability to formulate new political tropes that broke with the late-Qing imperial discourse and set the foundation for a "national" mode of political thinking. It was especially in the Three People's Principles that Sun translated into effective new political language the main intellectual trends that swept China in the latenineteenth and early-twentieth centuries. If we refrain from approaching the Principles from a Western-centered and presentist perspective-which inevitably makes them appear awkward vis-a-vis Western political discourses with which we are more readily familiar-and, instead, take into consideration their intellectual backdrop and Sun's political goals, we discover that the Principles estab-© Twentieth-Century China, Vol. 30, NO.1 (November 2004): 6-38. 2004 FOSTERING THE PEOPLE'S LIVELIHOOD 7 lished new conceptual categories for imagining China's national political life and for discussing such crucial issues as "people" and "poverty" outside of the parameters of the imperial discourse. In fact, GMD mythologizing damaged Sun's posthumous image in at least one major way. While it boosted Sun's image to a position he had never really reached before his death in 1925, it also initiated a vulgarization of Sun's thought, by transforming it into predictable propaganda. In other words, the GMD ossified the Principles into meaningless slogans that obliterated their importance in the transformation of Chinese political thought from imperial (specifically late-Qing) to "national." The development of the Principles illustrates, however, that this transformation was neither simple nor clear-cut. Even for thinkers like Sun Vat-sen, who aimed at overthrowing the imperial system and its ideological foundations, conceptual categories constructed by the imperial political discourse continued to exercise considerable influence. Sun's development of the Principle of People's Livelihood and the appropriation of this Principle by GMD leaders after Sun's death offer a most glaring example. In his early writings, Sun used this tropegenerally paired in imperial political rhetoric with state finance in the ubiquitous expression "state finance and people's livelihood (~*t ~~, guo}i minsheng)as an unquestioned conceptual category and without divesting it of most of the implications that it had carried in imperial political discourse. It was only in 1924, after it was used for years in the context...

Patterns of tropospheric response to solar variability

Despite numerous reports of apparent climate responses to the 11‐year solar cycle, the Sun's role for weather and climate has remained a matter of controversy. One important reason is the difficulty of reliably attributing the observed atmospheric effects to solar variability, rather than to other forcing factors or intrinsic variability. Here we show that consistent patterns of statistically significant solar signals emerge in all major observables throughout the low‐ and mid‐latitude troposphere, when El Niño and volcanic signals are removed from meteorological data. Solar forcing is strongest in the tropics and at mid‐latitudes, and the heating and moistening of the troposphere during solar maximum is accompanied by a modulation of the large‐scale tropospheric circulation systems. These findings have implications for the question of where and how the Sun exerts its influences in the climate system.

The Sun's role in climate variations.

Is the Sun the controller of climate changes, only the instigator of changes that are mostly forced by the system feedbacks, or simply a convenient scapegoat for climate variations lacking any other obvious cause? This question is addressed for suggested solar forcing mechanisms operating on time scales from billions of years to decades. Each mechanism fails to generate the expected climate response in important respects, although some relations are found. The magnitude of the system feedbacks or variability appears as large or larger than that of the solar forcing, making the Sun's true role ambiguous. As the Sun provides an explicit external forcing, a better understanding of its cause and effect in climate change could help us evaluate the importance of other climate forcings (such as past and future greenhouse gas changes).

Setting a conservative policy agenda: The Victorian print media, young people in care and chroming

The tabloid print media has played a crucial role in recent Australian social policy debates, particularly those pertaining to drug use and child and adolescent welfare. Much of the media's contribution has been around promoting simplistic and often conservative solutions to complex social problems.This article examines the recent media-inspired furore over so-called ‘safe-sniffing’ practices in a Victorian welfare agency. It is acknowledged that other forms of media such as talk back radio may have had influential roles, as might other factors also. Particular attention, however, is drawn here to the Herald Sun's role in this affair, and to similarities with its intervention in earlier policy debates. Some comparisons are also drawn with the coverage of the affair by the Age and the Australian.It is argued that the Herald Sun's specific campaign on chroming reflects a broader conservative agenda to undermine progressive social policy interventions including harm minimisation. This agenda may have significant implications for the Victorian community welfare sector given the tendency of politicians – whether in government or opposition – to bow to the demands of the tabloid media.

Solar variability and climate change: An historical perspective

There is nothing new about the debate over the Sun's influence on terrestrial climate.As early as the late 18th century, widespread concern for the deterioration of the Earth's climate led to speculation about the Sun's role in climate change [Feldman, 1993; Fleming, 1990]. Drawing analogies with variations in the brightness of stars, the British astronomer William Herschel suggested that greater sunspot activity would result in warmer terrestrial climates. Herschel supported his hypothesis by referring to price series for wheat published in Adam Smiths Wealth of Nations [Hufbauer, 1991]. Later, the eminent American physicist Joseph Henry demonstrated by thermopile measurements that, contrary to Herschel's assumption, sunspots were cooler than the unblemished portions of the solar disk.

The Sun's Role in Long-Term Climate Change

Evidence suggests that changes of solar irradiance in recent centuries have provided a significant climate forcing and that the sun has been one of the principal causes of long-term climate change. During the past two decades the solar forcing has been much smaller than the climate forcing caused by increasing greenhouse gases. But it is incorrect to assume that the sun necessarily will be an insignificant player in climate change of the 21st century. Indeed, I argue that moderate success in curtailing the growth of anthropogenic climate forcings could leave the sun playing a pivotal role in future climate change.

Sun's Role in Warming Is Discounted

The sun has become a factor in the debate over global warming because the measured temperature rise isn`t as large as some climate models predict. However, this article discusses recent research which concludes that solar variability...is at most a minor factor in the increase in average temperature observed over the last century. Others feel that the conclusions still need close examination because of such factors as increasing concentrations of fine aerosols which may even out warming between summer and winter.

The Earth's Climate and Variability of the Sun Over Recent Millennia

At the outer limits of the range of topics covered in these proceedings from a joint meeting of the British Royal Society and the French Academie des Sciences lie speculation and inaccessible places and times. The causes of the Sun's variability are hidden beneath its surface, and we can only speculate about whether solar magnetism, which provides the energy for the variations, is generated just below the surface or is a remnant of an ancient magnetism trapped in the core. An equally distant and inaccessible sphere is the gassy envelope around the prehistoric Earth where changes in climate presumably drove early man to alter his habits and homes. But as P. I. Kuniholm writes in this volume, climate change has often been appealed to in accounting for phenomena that cannot otherwise be accounted for. Archaeologists never imagined that physicists would try to reconstruct the Sun's past from such speculations. Between the two extremes of ignorance, however, a solid foundation is being built for a scientific account of the Sun's role in climate change.

Photosensitivity Disease: Principles of Diagnosis and Treatment

When two leaders in the field of photobiology collaborate, one would expect an outstanding textbook, and, fortunately, Drs Bicker and Harber don't disappoint. From the preface in which they target their audience—dermatologists, pediatricians, internists, and family practitioners—to their large color atlas of common and not-so-common clinical diseases, this text offers important detailed information to the clinician and investigator. The book is divided into five sections. A brief introduction on the sun's role in history and mythology acts as a gentle bridge into the second section on the physics of radiant energy. Third is a section dealing with the therapeutic effects of radiation ranging from psoralen—ultraviolet-A range (PUVA) light (for psoriasis and cutaneous T-cell lymphoma) to phototherapy (for neonatal jaundice). This part is very up to date as it includes information such as the new liquid formulation of psoralen. The fourth and largest part of the book covers the diagnosis and