Discovery of mass anomalies on Ganymede

We present the discovery of mass anomalies on Ganymede, Jupiter's third and largest Galilean satellite. This discovery is surprising for such a large icy satellite. We used the radio Doppler data generated with the Galileo spacecraft during its second encounter with Ganymede on 6 September 1996 to model the mass anomalies. Two surface mass anomalies, one a positive mass at high latitude and the other a negative mass at low latitude, can explain the data. There are no obvious geological features that can be identified with the anomalies.     

Comment on "The spatial extent of 20th-century warmth in the context of the past 1200 years"

Osborn and Briffa (Reports, 10 February 2006, p. 841) identified anomalous periods of warmth or cold in the Northern Hemisphere that were synchronous across 14 temperature-sensitive proxies. However, their finding that the spatial extent of 20th-century warming is exceptional ignores the effect of proxy screening on the corresponding significance levels. After appropriate correction, the significance of the 20th-century warming anomaly disappears.     

Periodic freshwater flooding and stagnation of the eastern mediterranean sea during the late quaternary

Major negative oxygen isotopic anomalies in planktonic foraminifera are associated with deep-sea anoxic mud layers (sapropels) deposited 9000 and 80,000 years ago in the eastern Mediterranean. The isotopic depletion in surface-dwelling foraminifera is significantly greater than in mesopelagic foraminifera. This difference in isotopic response suggests that surface-water salinities were drastically reduced during times of sapropel formation, possibly as the result of meltwater runoff from the Fennoscandian ice sheet into the eastern Mediterranean by way of the Black and Aegean seas.     

父母情感温暖与儿童正负情绪:心理素质和希望感的连续中介及差异

心理素质和希望感可能是父母情感温暖影响儿童情绪体验的内在机制.采用父母情感温暖量表、小学生心理素质问卷、儿童希望量表和正负性情绪量表,对1 350名小学生进行施测,结果发现:父母情感温暖可以通过儿童的心理素质和希望感提高/降低儿童的正性/负性情绪,其中正负2种情绪上的连续中介机制差异具有统计学意义.对于正性情绪,心理素质和希望只是部分中介的作用;对于负性情绪,则是完全中介,并且在希望的路径思维维度上出现了遮蔽效应.     

Experiencing physical warmth promotes interpersonal warmth

"Warmth" is the most powerful personality trait in social judgment, and attachment theorists have stressed the importance of warm physical contact with caregivers during infancy for healthy relationships in adulthood. Intriguingly, recent research in humans points to the involvement of the insula in the processing of both physical temperature and interpersonal warmth (trust) information. Accordingly, we hypothesized that experiences of physical warmth (or coldness) would increase feelings of interpersonal warmth (or coldness), without the person's awareness of this influence. In study 1, participants who briefly held a cup of hot (versus iced) coffee judged a target person as having a "warmer" personality (generous, caring); in study 2, participants holding a hot (versus cold) therapeutic pad were more likely to choose a gift for a friend instead of for themselves.     

Early irradiation of matter in the solar system: magnesium (proton, neutron) scheme

The occurrence of positive and negative (26)Mg anomalies in inclusions of the Allende meteorite is explained in terms of proton bombardment of a gas of solar composition. A significant fraction of (26)Mg in the irradiated gas is stored temporarily in the form of radioactive (26)Al by the reaction (26)Mg(p,n) (26)Al. Proton fluxes of 10(17) to 10(19) protons per square centimeter per year at l million electron volts are inferred. Aluminum-rich materials condensing from the gas phase have positive (26)Mg anomalies, whereas magnesium-rich materials have negative (26)Mg anomalies. The proton flux required to account for the observed magnesium anomalies is used to investigate possible isotopic anomalies in the elements from oxygen to argon. Detectable isotopic anomalies are predicted only for neon. The anomalous neon is virtually pure (22)Ne from (22)Na decay. The predicted amount of anomalous (22)Ne is about 10(-8) cubic centimeter (at standard temperature and pressure) per milligram of sodium.     

Upwelling intensification as part of the Pliocene-Pleistocene climate transition

A deep-sea sediment core underlying the Benguela upwelling system off southwest Africa provides a continuous time series of sea surface temperature (SST) for the past 4.5 million years. Our results indicate that temperatures in the region have declined by about 10 degrees C since 3.2 million years ago. Records of paleoproductivity suggest that this cooling was associated with an increase in wind-driven upwelling tied to a shift from relatively stable global warmth during the mid-Pliocene to the high-amplitude glacial-interglacial cycles of the late Quaternary. These observations imply that Atlantic Ocean surface water circulation was radically different during the mid-Pliocene.     

The hot summer of 2010: redrawing the temperature record map of Europe

The summer of 2010 was exceptionally warm in eastern Europe and large parts of Russia. We provide evidence that the anomalous 2010 warmth that caused adverse impacts exceeded the amplitude and spatial extent of the previous hottest summer of 2003. "Mega-heatwaves" such as the 2003 and 2010 events likely broke the 500-year-long seasonal temperature records over approximately 50% of Europe. According to regional multi-model experiments, the probability of a summer experiencing mega-heatwaves will increase by a factor of 5 to 10 within the next 40 years. However, the magnitude of the 2010 event was so extreme that despite this increase, the likelihood of an analog over the same region remains fairly low until the second half of the 21st century.     

流动儿童家庭社会经济地位与学业成绩:父母情感温暖和心理素质的链式中介作用

为探讨流动儿童家庭社会经济地位、父母情感温暖、心理素质和学业成绩4者之间的关系,以及父母情感温暖和心理素质在流动儿童家庭社会经济地位与学业成绩间所起的作用,以707名流动儿童为被试,采用家庭社会经济地位问卷、父母情感温暖问卷、小学生心理素质问卷进行测试,同时收集学生的学业成绩.结果发现:(1)家庭社会经济地位、父母情感温暖、心理素质和学业成绩之间两两均呈显著正相关.(2)父母情感温暖和心理素质在家庭社会经济地位与学业成绩之间的链式中介作用显著,家庭社会经济地位对学业成绩的直接效应也显著,中介效应占总效应的25.3%.家庭社会经济地位既通过直接路径,也通过父母情感温暖和心理素质链式中介作用的间接路径影响流动儿童的学业成绩.     

Micropaleontological evidence for increased meridional heat transport in the north atlantic ocean during the pliocene

The Middle Pliocene ( approximately 3 million years ago) has been identified as the last time the Earth was significantly warmer than it was during the Last Interglacial and Holocene. A quantitative micropaleontological paleotemperature transect from equator to high latitudes in the North Atlantic indicates that Middle Pliocene warmth involved increased meridional oceanic heat transport.     

Afterimage of perceptually filled-in surface

An afterimage induced by prior adaptation to a visual stimulus is believed to be due to bleaching of photochemical pigments or neural adaptation in the retina. We report a type of afterimage that appears to require cortical adaptation. Fixating a neon-color spreading configuration led not only to negative afterimages corresponding to the inducers (local afterimages), but also to one corresponding to the perceptually filled-in surface during adaptation (global afterimage). These afterimages were mutually exclusive, undergoing monocular rivalry. The strength of the global afterimage correlated to a greater extent with perceptual filling-in during adaptation than with the strength of the local afterimages. Thus, global afterimages are not merely by-products of local afterimages, but involve adaptation at a cortical representation of surface.     

Crustal Thickness on the Mid-Atlantic Ridge: Bull's-Eye Gravity Anomalies and Focused Accretion

Spreading segments of the Mid-Atlantic Ridge show negative bull's-eye anomalies in the mantle Bouguer gravity field. Seismic refraction results from 33 degrees S indicate that these anomalies can be accounted for by variations in crustal thickness along a segment. The crust is thicker in the center and thinner at the end of the spreading segment, and these changes are attributable to variations in the thickness of layer 3. The results show that accretion is focused at a slow-spreading ridge, that axial valley depth reflects the thickness of the underlying crust, and that along-axis density variations should be considered in the interpretation of gravity data.     

Decadal trends in the north atlantic oscillation: regional temperatures and precipitation

Greenland ice-core data have revealed large decadal climate variations over the North Atlantic that can be related to a major source of low-frequency variability, the North Atlantic Oscillation. Over the past decade, the Oscillation has remained in one extreme phase during the winters, contributing significantly to the recent wintertime warmth across Europe and to cold conditions in the northwest Atlantic. An evaluation of the atmospheric moisture budget reveals coherent large-scale changes since 1980 that are linked to recent dry conditions over southern Europe and the Mediterranean, whereas northern Europe and parts of Scandinavia have generally experienced wetter than normal conditions.     

Magnetic Anomalies over the Pacific-Antarctic Ridge

Four magnetic profiles across the Pacific-Antarctic Ridge reveal magnetic anomalies that show trends parallel with the ridge axis and symmetry about the ridge axis. The distribution of bodies that could cause these anomalies supports the Vine and Matthews hypothesis for the generation of patterns of magnetic anomalies associated with the midocean ridge system. The geometry of the bodies accords with the known reversals of the geomagnetic field during the last 3.4 million years, indicating a spreading rate of the ocean floor of 4.5 centimeters per year. If one assume that the spreading rate within 500 kilometers of the ridge axis has been constant, reversals of the geomagnetic field during the last 10.0 million years can be determined. This new, detailed history of field reversals accords with observed anomalies over Reykjanes Ridge in the North Atlantic if a spreading rate of 1 centimeter per year is assumed there.     

Isotopic evidence for glaciation during the Cretaceous supergreenhouse

The Turonian (93.5 to 89.3 million years ago) was one of the warmest periods of the Phanerozoic eon, with tropical sea surface temperatures over 35 degrees C. High-amplitude sea-level changes and positive delta18O excursions in marine limestones suggest that glaciation events may have punctuated this episode of extreme warmth. New delta18O data from the tropical Atlantic show synchronous shifts approximately 91.2 million years ago for both the surface and deep ocean that are consistent with an approximately 200,000-year period of glaciation, with ice sheets of about half the size of the modern Antarctic ice cap. Even the prevailing supergreenhouse climate was not a barrier to the formation of large ice sheets, calling into question the common assumption that the poles were always ice-free during past periods of intense global warming.     

Amplification of Cretaceous warmth by biological cloud feedbacks

The extreme warmth of particular intervals of geologic history cannot be simulated with climate models, which are constrained by the geologic proxy record to relatively modest increases in atmospheric carbon dioxide levels. Recent recognition that biological productivity controls the abundance of cloud condensation nuclei (CCN) in the unpolluted atmosphere provides a solution to this problem. Our climate simulations show that reduced biological productivity (low CCN abundance) provides a substantial amplification of CO2-induced warming by reducing cloud lifetimes and reflectivity. If the stress of elevated temperatures did indeed suppress marine and terrestrial ecosystems during these times, this long-standing climate enigma may be solved.     

Aeromagnetic and radio echo ice-sounding measurements show much greater area of the dufek intrusion, antarctica

A combined aeromagnetic and radio echo ice-sounding survey made in 1978 in Antarctica over the Dufek layered mafic intrusion suggests a minimum area of the intrusion of about 50,000 square kilometers, making it comparable in size with the Bushveld Complex of Africa. Comparisons of the magnetic and subglacial topographic profiles illustrate the usefulness of this combination of methods in studying bedrock geology beneath ice-covered areas. Magnetic anomalies range in peak-to-through amplitude from about 50 nanoteslas over the lowermost exposed portion of the section in the Dufek Massif to about 3600 nanoteslas over the uppermost part of the section in the Forrestal Range. Theoretical magnetic anomalies, computed from a model based on the subice topography fitted to the highest amplitude observed magnetic anomalies, required normal and reversed magnetizations ranging from 10(-3) to 10(-2) electromagnetic units per cubic centimeter. This result is interpreted as indicating that the Dufek intrusion cooled through the Curie isotherm during one or more reversals of the earth's magnetic field.     

皖北地区的气温变率研究

采用线性倾向估计、累积距平和突变检测方法,对皖北地区1958～2007年的四季、年气温资料进行综合分析。结果表明,近50 a皖北地区年平均气温呈明显的上升趋势,线性气温倾向率介于0.16～0.34℃/10a;最大增暖发生在冬季、春季;年代际变化趋势为先降后升,20世纪60～80年代,区域年温平均距平值均为负值,为相对冷期,90年代和2000～2007年2个时段的年温平均距平值均为正值,为相对暖期。突变分析结果显示,皖北地区的气温变化存在明显突变现象,突变时间发生在20世纪80年代末到21世纪初。     

Planetary-scale forcing of the january 1977 weather

The type of weather anomalies that occurred in the United States during January 1977 are typical of a planetary-scale wave phenomenon called stratospheric sudden warming (SSW). Specific changes in weather parameters nearly always accompany SSW. Blocking ridges (intensified high-pressure cells) develop over the oceans, the North Pole warms, mid-latitudes cool, and continental temperatures plunge. These characteristics usually persist for at least a month. When the SSW is strong, as in January 1958, 1963, and 1977, the accompanying weather anomalies can be unusually severe.