Carbon dioxide in surface seawater of the eastern North Pacific Ocean (Line P), 1973–2005     

C.S. Wong  James R. Christian  S.-K. Emmy Wong  John Page  Liusen Xie  Sophia Johannessen 《Deep Sea Research Part I: Oceanographic Research Papers》2010,57(5):687-695

Partial pressure of CO₂ (pCO₂) in surface seawater has been measured in the northeastern Pacific Ocean at Station P and along Line P since 1973. These data have been divided into ‘oceanic’ and ‘coastal/transition’ zones, and the seasonal and interannual variability and the long-term trends for each zone have been examined. The oceanic zone shows little seasonality in surface seawater pCO₂, with undersaturation throughout the year. A strong, biologically-driven seasonal cycle is offset by variation in temperature-dependent solubility of CO₂. The coastal/transition zone shows a decline in pCO₂ from winter–spring through summer and fall that is likely the result of seasonal stratification and convection rather than coastal upwelling. Interannual variability all along Line P is correlated with the multivariate ENSO index (MEI), with lower seawater pCO₂ associated with El Niño conditions. Correlations with the Pacific Decadal Oscillation Index are similar but weaker, in part because there are few data prior to the 1976 regime shift. The long-term trend in seawater pCO₂ in the oceanic zone is +1.36±0.16 μatm year^?1, indistinguishable from the atmospheric growth rate, and varies little among the seasons. In the coastal/transition zone a slow increase in the pCO₂ of surface seawater relative to that of the atmosphere has led to increasing undersaturation, particularly in spring. Aliasing of the seasonal and interannual variability due to sampling frequency may explain part of the observed trend in the coastal/transition zone, but real changes in physical or biological processes are also possible and require more detailed study.  相似文献   

Combined long and short time-scale X-ray variability of NGC 4051 with RXTE and XMM–Newton     

I. M. MHardy  I. E. Papadakis  P. Uttley  M. J. Page  K. O. Mason 《Monthly notices of the Royal Astronomical Society》2004,348(3):783-801

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The discovery of a significant sample of massive galaxies at redshifts 5 < z < 6 in the UKIDSS Ultra Deep Survey early data release     

R. J. McLure  M. Cirasuolo  J. S. Dunlop  K. Sekiguchi  O. Almaini  S. Foucaud  C. Simpson  M. G. Watson  P. Hirst  M. J. Page  I. Smail 《Monthly notices of the Royal Astronomical Society》2006,372(1):357-368

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XMM–Newton observations of high-luminosity radio-quiet quasi-stellar objects     

K. L. Page  J. N. Reeves  P. T. O'Brien  M. J. L. Turner  D. M. Worrall 《Monthly notices of the Royal Astronomical Society》2004,353(1):133-142

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Possible remnants of a frozen mud lake in southern Elysium, Mars     

Konrad J. Kossacki  Wojciech J. Markiewicz  David Page 《Icarus》2006,181(2):363-374

In this work we estimate the minimum persistence time of subsurface ice in water rich sediment layers remaining after sublimation of a martian lake. We simulate sublimation of ice from layers of different granulations and thicknesses. Presented results assume insolation and atmospheric conditions characteristic for the present day southern Elysium, where data from Mars Express have identified surface features possibly indicating the very recent presence of a frozen body of water [Murray et al., 2005. Nature 434, 352-356]. The age of these features is estimated to be several million years. On this time scale, we find that most of the water ice must have sublimated away, however remnant ice at a few percent level cannot be excluded. This amount of water ice is sufficient for chemical cementation of the observed features and explains their relatively pristine appearance, without significant signs of erosion.  相似文献   

XMM–Newton 13^H deep field – I. X-ray sources     

N. S. Loaring  T. Dwelly  M. J. Page  K. Mason  I. McHardy  K. Gunn  D. Moss  N. Seymour  A. M. Newsam  T. Takata  K. Sekguchi  T. Sasseen  F. Cordova 《Monthly notices of the Royal Astronomical Society》2005,362(4):1371-1395

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A simultaneous XMM–Newton and BeppoSAX observation of the archetypal broad line Seyfert 1 galaxy NGC 5548     

K. A. Pounds  J. N. Reeves  K. L. Page  R. Edelson  G. Matt  G. C. Perola 《Monthly notices of the Royal Astronomical Society》2003,341(3):953-960

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XMM–Newton observations of 3C 273     

K. L. Page  M. J. L. Turner  C. Done  P. T. O'Brien  J. N. Reeves  S. Sembay  M. Stuhlinger 《Monthly notices of the Royal Astronomical Society》2004,349(1):57-67

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XMM–Newton RGS spectroscopy of LMC X-3     

M. J. Page  R. Soria  K. Wu  K. O. Mason  F. A. Cordova  W. C. Priedhorsky 《Monthly notices of the Royal Astronomical Society》2003,345(2):639-649

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Economically consistent long-term scenarios for air pollutant emissions   总被引：1，自引：0，他引：1  

Steven J. Smith  J. Jason West  Page Kyle 《Climatic change》2011,108(3):619-627

Pollutant emissions such as aerosols and tropospheric ozone precursors substantially influence climate. While future century-scale scenarios for these emissions have become more realistic through the inclusion of emission controls, they still potentially lack consistency between surface pollutant concentrations and regional levels of affluence. We find that the default method of scenario construction, whereby emissions factors converge to similar values in different regions, does not yield pollution concentrations consistent with historical experience. We demonstrate a methodology combining use of an integrated assessment model and a three-dimensional atmospheric chemical transport model, whereby a reference scenario is constructed by requiring consistent surface pollutant concentrations as a function of regional income over the 21st century. By adjusting air pollutant emission control parameters, we improve consistency between projected PM_2.5 and economic income among world regions through time; consistency for ozone is also improved but is more difficult to achieve because of the strong influence of upwind world regions. Reference case pollutant emissions described here were used to construct the RCP4.5 Representative Concentration Pathway climate policy scenario.  相似文献