Reply to Phillips     

Robert F. Austin 《The Professional geographer》1983,35(2):195-196

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High-frequency oscillations in the corona observed at the 1983 eclipse     

Jay M. Pasachoff  Edwin F. Ladd 《Solar physics》1987,109(2):365-372

We detected excess oscillatory power at 0.25–2.0 Hz in a coronal loop in the 1983 Indonesian total solar eclipse. In this second-generation experiment enlarging upon the work of Pasachoff and Landman (1984), we observed in two frequency channels, one coronal and one continuum, to monitor atmospheric and instrumental effects. We briefly discuss the effects of an oscillation near 1 Hz on the coronal heating problem.Visiting Colleague, Institute for Astronomy, University of Hawaii.  相似文献   

Abstracts of papers from other journals     

Jay M. Pasachoff  G. Y. Vassilyeva  J. -C. Henoux  N. Stepanyan 《Solar physics》1968,5(4):588-591

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A Review of Tidal, Earth Normal Mode and Seismic Data Obtained with Quartz Torsion Accelerometers     

Barry Block  Jay Dratler 《Geophysical Journal International》1972,31(1-3):239-269

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Foraminifera from the Irish Sea glacigenic deposits at Aberdaron,western Lleyn,North Wales: Palaeoenvironmental implications     

William E. N. Austin  Danny McCarroll 《第四纪科学杂志》1992,7(4):311-317

In a sequence of glacigenic sediments at Aberdaron, Foraminifera were obtained from samples located specifically in order to differentiate between opposing models of depositional environment. All the diamict samples yielded remarkably uniform assemblages, with similar numbers of benthic specimens and benthic species per unit weight of sediment, similar planktic : benthic ratios, and similar ratios of clearly allochthonous to possibly autochthonous elements. This is precisely as predicted by the terrestrial model of sedimentation, where all of the sediments are interpreted as being derived from the melting of glacier ice rich in marine debris entrained during passage along the Irish Sea Basin. The results lend no support to a glacial marine model, since no faunal responses to increasingly distal sedimentary environments are observed. However, the fauna is dominated by the Foraminifera Elphidium excavatum (Terquem) forma clavata Cushman, which is commonly assumed to indicate glacial marine conditions. The modern distribution of similar assemblages suggests that it is just as likely to represent the cold, reduced salinity conditions that would have prevailed in the northern Irish Sea Basin for much of the Quaternary.  相似文献   

Regional Considerations of Coastline Change,Tsunami Damage and Recovery along the Southern Coast of the Bay of Izmit (The Kocaeli (Turkey) Earthquake of 17 August 1999)     

Rothaus  Richard M.  Reinhardt  Eduard  Noller  Jay 《Natural Hazards》2004,31(1):233-252

Co-seismic phenomena along the south coastline included liquefaction, subsidenceand tsunami. Construction on areas composed of fluvial and alluvial sediments aswell as unconsolidated fill increased the risk by creating potential for amplificationof seismic waves. Cyclic mobility liquefaction was common along the coastline, andlevel-ground liquefaction was observed. Flow liquefaction is held forth as a possibilityin the Deirmendere submarine landslide. Damage to structures was markedly more in areas of unconsolidated sediments. One or more tsunami struck immediately after the event; the uniformity of tsunami impact indicating a wave coming from 310° suggests that submarine faulting was the major source of tsunami. Over 800,000 m² of subsidence resulted from sediment slumping, fault controlled subsidence, and possibly post-liquefaction sediment compaction. After a brief period of post-event abandonment, reclamation and use of coastal areas is well underway. This creates a tension between human desires pushing for quick and inexpensive re-inhabitation of the coastal areas, and the needs for zoning and building codes for risk reduction. In this high-risk area suchcontrary cultural mandates cannot yield ideal results. It is suggested that an alternativemodel of immediate post-event creation of parks and natural areas that would yield benefit is preferable in coastal areas rather than the enforcement approach currently favored.  相似文献   

Total and methylmercury in three species of sea turtles of Baja California Sur     

Kampalath R  Gardner SC  Méndez-Rodríguez L  Jay JA 《Marine pollution bulletin》2006,52(12):1816-1823

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De(re)forestation and climate warming in subarctic China     

Jay Gao  Yansui Liu 《Applied geography (Sevenoaks, England)》2012,32(2):281-290

Although tropical deforestation bears a close relationship with climate change, its exact contribution to climate warming and its threshold of exerting a noticeable influence remain unknown. This study attempts to bridge this knowledge gap by analyzing deforestation data of Heilongjiang Province, China in relation to climate data. It is found that forest cover was reduced from 238,335 km² in 1958 to 216,009 km² in 1980, and further to 207,629 km² in 2000. During this period the provincial annual temperature rose by 1.68 °C, against the nation-wide warming of 0.99 °C during the same period. At the provincial level the observed deforestation caused a warming in the vicinity of 0.69 °C. This warming does not bear any definite relationship with latitude and elevation. At the local scale, deforestation is related inversely to the rise in decadal temperature in the form of ΔT = −0.013ΔF + 0.4114 (R² = 0.30). There is a positive relationship between the accuracy (R² value) of predicting climate warming from deforestation and its severity. The critical threshold for deforestation to exert a noticeable impact on climate warming (e.g., R² = 50%) appears to be 5 km². The amount of forest cover at the beginning of a period can inhibit temperature rise, but its exact effect on climate warming is difficult to quantify.  相似文献   

Scientific observations at total solar eclipses   总被引：1，自引：0，他引：1  

Jay M. Pasachoff 《天体物理学报》2009,(6):613-634

The occasion of the longest totality of an eclipse in the 18 yr 11^1/3 d saros cycle leads to taking stock of the scientific value of ground-based eclipse observations in this space age. Though a number of space satellites from the U.S., Europe, Japan, and Russia study the Sun, scientists at eclipses can observe the solar chromosphere and corona at higher spatial resolution, at higher temporal resolution, and at higher spectral resolution than are possible aloft. Furthermore, eclipse expeditions can transport a wide variety of state-of-the-art equipment to the path of totality. Thus, for at least some years to come, solar eclipse observations will remain both scientifically valuable and cost-effective ways to study the outer solar atmosphere.  相似文献   

东北地区农业结构转型时期土地利用变化的成因与效应     

刘彦随  甘红  Jay GAO  DENG Xusheng 《地理学报(英文版)》2004,14(4):488-494

During the last decade of the 20th century, extensive conversion in agricultural land use took place in Northeast China. The goal of this study is to ascertain its spatial distribution and regional differentiation, determine its causes, and analyze its environmental impact, Especially we attempt to elucidate how institutional constraints have facilitated the change at a time of agrarian restructuring when newly emerging free market was hybridized with the former planned economy. Information on six categories of land use was mapped from interpretation of Landsat TM images recorded in 1990,1995 and 2000. Most of land use changes took place during the first half of the decade, coinciding with abrupt and chaotic changes in government directives. Farmland was changed mainly to woodland,water body and built-up areas while woodland and grassland were converted chiefly to farmland.Spatially, the change from farmland to woodland was restricted to the west of the study area. The change from grassland to farmland took place in the grazing and farming interlocked west. These chaotic and occasionally conflicting changes were largely caused by lack of stability and consistency in agricultural land use policies promulgated. They have exerted adverse impacts on the local environment, including land degradation, increased flooding, and modified climate regime.  相似文献