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141.
aam, m ¶rt;-mau ¶rt;uu a ma au am m¶rt; ma m unmuu m m. ¶rt;a, u a u unmuu annuuam, m am n una u 0,1 u a u ammuuu ¶rt;mau aa m m. 相似文献
142.
Analyzing daily values of the total solar irradiance (TSI), the coronal index of solar activity (CI), and the Mg II 280-nm
core-to-wing ratio (Mg II index), we have found that the temporal variations of these indices are very similar to each other
during the period from 1978 to 2005. The correlation between CI and TSI, with the PSI correction lying within the interval
under study, has been found to be 0.699, which is very close to the value of 0.703 of the correlation between Mg II and TSI
for 27-day averages (the CI – Mg correlation is 0.824). The regression equation between CI and TSI is almost linear, except
for TSI depletions when a large number of sunspots are present on the visible disk. By employing CI, an extrapolation of TSI
back to 1947 is presented. 相似文献
143.
Milan M. Ćirković 《Earth, Moon, and Planets》2002,91(4):243-254
We consider the little-known anthropic argument of Fontenelledealing with the nature of cometary orbits, given a year before the publication of Newton'sPrincipia. This is particularly interesting in view of the rapid development of therecently resurgent theories of cometary catastrophism and their role in the modern astrobiologicaldebates, for instance in the ``rare Earth' hypothesis of Ward and Brownlee. 相似文献
144.
Gareth Chisham, Gary Abel and Steve Milan report on the October 2003 RAS "G" discussion meeting "Identifying the open–closed field line boundary in magnetospheric and ionospheric data sets". 相似文献
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146.
AbstractStatistically significant FAO-56 Penman-Monteith (FAO-56 PM) and adjusted Hargreaves (AHARG) reference evapotranspiration (ET0) trends at monthly, seasonal and annual time scales were analysed by using linear regression, Mann-Kendall and Spearman’s Rho tests at the 1 and 5% significance levels. Meteorological data were used from 12 meteorological stations in Serbia, which has a humid climate, for the period 1980–2010. Web-based software for conducting the trend analyses was developed. All of the trends significant at the 1 and 5% significance levels were increasing. The FAO-56 PM ET0 trends were almost similar to the AHARG trends. On the seasonal time scale, for the majority of stations significant increasing trends occurred in summer, while no significant positive or negative trends were detected by the trend tests in autumn for the AHARG series. Moreover, 70% of the stations were characterized by significant increasing trends for both annual ET0 series. Editor Z.W. Kundzewicz; Associate editor S. GrimaldiCitation Gocic, M. and Trajkovic, S., 2013. Analysis of trends in reference evapotranspiration data in a humid climate. Hydrological Sciences Journal, 59 (1), 165–180. 相似文献
147.
S. Sembay G. Branduardi‐Raymont J.P. Eastwood D.G. Sibeck A. Abbey P. Brown J.A. Carter C.M. Carr C. Forsyth D. Kataria S. Kemble S. Milan C.J. Owen A.M. Read L. Peacocke C.S. Arridge A.J. Coates M.R. Collier S.W.H. Cowley A.N. Fazakerley G. Fraser G.H. Jones R. Lallement M. Lester F.S. Porter T. Yeoman 《Astronomische Nachrichten》2012,333(4):388-392
AXIOM (Advanced X‐ray Imaging Of the Magnetosphere) is a concept mission which aims to explain how the Earth's magnetosphere responds to the changing impact of the solar wind using a unique method never attempted before; performing wide‐field soft X‐ray imaging and spectroscopy of the magnetosheath, magnetopause and bow shock at high spatial and temporal resolution. Global imaging of these regions is possible because of the solar wind charge exchange (SWCX) process which produces elevated soft X‐ray emission from the interaction of high charge‐state solar wind ions with primarily neutral hydrogen in the Earth's exosphere and near‐interplanetary space (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
148.
Helaine W. Markewich Ronald J. Litwin Milan J. Pavich George A. Brook 《Quaternary Research》2009,71(3):409-425
Inactive parabolic dunes are present in southeastern Maryland, USA, along the east bank of the Potomac River. More elongate and finer-grained eolian deposits and paha-like ridges characterize the Potomac River–Patuxent River upland and the west side of Chesapeake Bay. These ridges are streamlined erosional features, veneered with eolian sediment and interspersed with dunes in the low-relief headwaters of Potomac- and Patuxent-river tributaries. Axis data for the dunes and ridges indicate formation by WNW–NW winds. Optically stimulated luminescence and radiocarbon age data suggest dune formation from 33–15 ka, agreeing with the 30–13 ka ages Denny, C.S., Owens, J.P., Sirkin, L., Rubin, M., 1979. The Parsonburg Sand in the central Delmarva Peninsula, Maryland and Delaware. U.S. Geol. Surv. Prof. Pap. 1067-B, 16 pp. suggested for eolian deposits east of Chesapeake Bay. Age range and paleowind direction(s) for eolian features in the Bay region approximate those for late Wisconsin loess in the North American midcontinent. Formation of midcontinent loess and Bay-region eolian features was coeval with rapid growth of the Laurentide Ice Sheet and strong cooling episodes (δ18O minima) evident in Greenland ice cores. Age and paleowind-direction coincidence, for eolian features in the midcontinent and Bay region, indicates strong mid-latitude WNW–NW winds for several hundred kilometers south of the Laurentide glacial terminus that were oblique to previously simulated anticyclonic winds for the last glacial maximum. 相似文献
149.
150.
Summary The gravitational potential energy of the Sun and its corresponding internal energy have been estimated on the basis of the
standard model of the Sun's internal structure. It is demonstrated that the principal moment of inertia of the Sun, computed
from the model, does not fit the hydrostatic equilibrium limit. 相似文献