Incorporation of ice sheet models into an Earth system model: Focus on methodology of coupling     

Oleg Rybak  Evgeny Volodin  Polina Morozova  Artiom Nevecherja 《Journal of Earth System Science》2018,127(2):28

Elaboration of a modern Earth system model (ESM) requires incorporation of ice sheet dynamics. Coupling of an ice sheet model (ICM) to an AOGCM is complicated by essential differences in spatial and temporal scales of cryospheric, atmospheric and oceanic components. To overcome this difficulty, we apply two different approaches for the incorporation of ice sheets into an ESM. Coupling of the Antarctic ice sheet model (AISM) to the AOGCM is accomplished via using procedures of resampling, interpolation and assigning to the AISM grid points annually averaged meanings of air surface temperature and precipitation fields generated by the AOGCM. Surface melting, which takes place mainly on the margins of the Antarctic peninsula and on ice shelves fringing the continent, is currently ignored. AISM returns anomalies of surface topography back to the AOGCM. To couple the Greenland ice sheet model (GrISM) to the AOGCM, we use a simple buffer energy- and water-balance model (EWBM-G) to account for orographically-driven precipitation and other sub-grid AOGCM-generated quantities. The output of the EWBM-G consists of surface mass balance and air surface temperature to force the GrISM, and freshwater run-off to force thermohaline circulation in the oceanic block of the AOGCM. Because of a rather complex coupling procedure of GrIS compared to AIS, the paper mostly focuses on Greenland.  相似文献   

Gradient-based Pareto optimal history matching for noisy data of multiple types     

Oleg Volkov  Vladislav Bukshtynov  Louis J. Durlofsky  Khalid Aziz 《Computational Geosciences》2018,22(6):1465-1485

The advantages of the simultaneous integration of production and time-lapse seismic data for history matching have been demonstrated in a number of previous studies. Production data provide accurate observations at particular spatial locations (wells), while seismic data enable global, though filtered/noisy, estimates of state variables. In this work, we present an efficient computational tool for bi-objective history matching, in which data misfits for both production and seismic measurements are minimized using an adjoint-gradient approach. This enables us to obtain a set of Pareto optimal solutions defining the optimal trade-off between production and seismic data misfits (which are, to some extent, conflicting). The impact of noise structure and noise level on Pareto optimal solutions is investigated in detail. We discuss the existence of the “best” trade-off solution, or least-conflicting posterior model, which corresponds to the history-matched model that is expected to provide the least-conflicting forecast of future reservoir performance. The overall framework is successfully applied in 2D and 3D compositional simulation problems to provide a single least-conflicting posterior model and, for the 2D case, multiple samples from the posterior distribution using the randomized maximum likelihood method.  相似文献   

What causes the spread of model projections of ocean dynamic sea-level change in response to greenhouse gas forcing?     

Couldrey  Matthew P.  Gregory  Jonathan M.  Boeira Dias  Fabio  Dobrohotoff  Peter  Domingues  Catia M.  Garuba  Oluwayemi  Griffies  Stephen M.  Haak  Helmuth  Hu  Aixue  Ishii  Masayoshi  Jungclaus  Johann  Köhl  Armin  Marsland  Simon J.  Ojha  Sayantani  Saenko  Oleg A.  Savita  Abhishek  Shao  Andrew  Stammer  Detlef  Suzuki  Tatsuo  Todd  Alexander  Zanna  Laure 《Climate Dynamics》2021,56(1-2):155-187

Sea levels of different atmosphere–ocean general circulation models (AOGCMs) respond to climate change forcing in different ways, representing a crucial uncertainty in climate change research. We isolate the role of the ocean dynamics in setting the spatial pattern of dynamic sea-level (ζ) change by forcing several AOGCMs with prescribed identical heat, momentum (wind) and freshwater flux perturbations. This method produces a ζ projection spread comparable in magnitude to the spread that results from greenhouse gas forcing, indicating that the differences in ocean model formulation are the cause, rather than diversity in surface flux change. The heat flux change drives most of the global pattern of ζ change, while the momentum and water flux changes cause locally confined features. North Atlantic heat uptake causes large temperature and salinity driven density changes, altering local ocean transport and ζ. The spread between AOGCMs here is caused largely by differences in their regional transport adjustment, which redistributes heat that was already in the ocean prior to perturbation. The geographic details of the ζ change in the North Atlantic are diverse across models, but the underlying dynamic change is similar. In contrast, the heat absorbed by the Southern Ocean does not strongly alter the vertically coherent circulation. The Arctic ζ change is dissimilar across models, owing to differences in passive heat uptake and circulation change. Only the Arctic is strongly affected by nonlinear interactions between the three air-sea flux changes, and these are model specific.

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Evidence for Extensive Proterozoic Remobilization of the Aldan Shield and Implication for Proterozoic Plate Tectonic Reconstructions of Siberia and Laurentia     

Oleg V. Avchenko  B. Ronald Frost  Kevin R. Chamberlain  Carol D. Frost 《Gondwana Research》2001,4(4):566-567

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Scientific program construction principles and time allocation scheme for the World Space Observatory—Ultraviolet mission     

Oleg Malkov  Mikhail Sachkov  Boris Shustov  Pavel Kaigorodov  Francisco Javier Yáñez  Ana Ines Gómez de Castro 《Astrophysics and Space Science》2011,335(1):323-327

We present scientific program construction principles and a time allocation scheme developed for the World Space Observatory—Ultraviolet (WSO-UV) mission, which is an international space observatory for observation in UV spectral range 100–300 nm. The WSO-UV consists of a 1.7 m aperture telescope with instrumentation designed to carry out high resolution spectroscopy, long-slit low resolution spectroscopy and direct sky imaging. The WSO-UV Ground Segment is under development by Spain and Russia. They will coordinate the Mission and Science Operations and provide the satellite tracking stations for the project.  相似文献   

Prospective spacecraft for venus research: Venera-D design     

V. A. Vorontsov  M. G. Lokhmatova  M. B. Martynov  K. M. Pichkhadze  A. V. Simonov  V. V. Khartov  L. V. Zasova  L. M. Zelenyi  O. I. Korablev 《Solar System Research》2011,45(7):710-714

A new phase of Venus research has started in Russia; the Federal Space Program includes the Venera-D design with the launch of the spacecraft scheduled for 2016. The mission comprises an orbiter, a descent vehicle, and balloon probes. The balloon probes will be placed at different altitudes in the cloud layer and under the clouds, where they are intended to last for a long time in the atmosphere of Venus. The successful implementation of the design will allow solving of quite a number of scientific tasks for comparative planetology.  相似文献   

Vertical profiling of SO2 and SO above Venus’ clouds by SPICAV/SOIR solar occultations     

Denis A. Belyaev  Franck Montmessin  Jean-Loup Bertaux  Arnaud Mahieux  Anna A. Fedorova  Oleg I. Korablev  Emmanuel Marcq  Yuk L. Yung  Xi Zhang 《Icarus》2012,217(2):740-751

New measurements of sulfur dioxide (SO₂) and monoxide (SO) in the atmosphere of Venus by SPICAV/SOIR instrument onboard Venus Express orbiter provide ample statistics to study the behavior of these gases above Venus’ clouds. The instrument (a set of three spectrometers) is capable to sound atmospheric structure above the clouds in several observation modes (nadir, solar and stellar occultations) either in the UV or in the near IR spectral ranges. We present the results from solar occultations in the absorption ranges of SO₂ (190–230 nm, and at 4 μm) and SO (190–230 nm). The dioxide was detected by the SOIR spectrometer at the altitudes of 65–80 km in the IR and by the SPICAV spectrometer at 85–105 km in the UV. The monoxide’s absorption was measured only by SPICAV at 85–105 km. We analyzed 39 sessions of solar occultation, where boresights of both spectrometers are oriented identically, to provide complete vertical profiling of SO₂ of the Venus’ mesosphere (65–105 km). Here we report the first firm detection and measurements of two SO₂ layers. In the lower layer SO₂ mixing ratio is within 0.02–0.5 ppmv. The upper layer, also conceivable from microwave measurements by Sandor et al. (Sandor, B.J., Todd Clancy, R., Moriarty-Schieven, G., Mills, F.P. [2010]. Icarus 208, 49–60) is characterized by SO₂ increasing with the altitude from 0.05 to 2 ppmv, and the [SO₂]/[SO] ratio varying from 1 to 5. The presence of the high-altitude SO_x species could be explained by H₂SO₄ photodissociation under somewhat warmer temperature conditions in Venus mesosphere. At 90–100 km the content of the sulfur dioxide correlates with temperature increasing from 0.1 ppmv at 165–170 K to 0.5–1 ppmv at 190–192 K. It supports the hypothesis of SO₂ production by the evaporation of H₂SO₄ from droplets and its subsequent photolysis at around 100 km.  相似文献   

AOST: Fourier spectrometer for studying mars and phobos     

O. I. Korablev  A. V. Grigor’ev  B. E. Moshkin  L. V. Zasova  F. Montmessin  A. B. Gvozdev  V. N. Shashkin  D. V. Patsaev  V. S. Makarov  S. V. Maksimenko  N. I. Ignatiev  A. A. Fedorova  G. Arnold  A. V. Shakun  A. I. Terentiev  A. V. Zharkov  B. S. Mayorov  Yu. V. Nikol’sky  I. V. Khatuntsev  G. Bellucci  M. Giuranna  R. O. Kuz’min  A. V. Rodin 《Solar System Research》2012,46(1):31-40

An AOST Fourier spectrometer of the Phobos-Soil project is intended for studying Mars and Phobos by means of measurements of IR radiation spectra of the Martian surface and atmosphere, the Phobos surface, and the spectrum of solar radiation passing through the Martian atmosphere on its limb. The main scientific problems to be solved with the spectrometer on Mars are measurements of methane content, search for minor constituents, and study of diurnal variations in the temperature and atmospheric aerosol. The spectrometer will also study the Martian and Phobos surface both remotely and after landing. The spectral range of the instrument is 2.5?C25 ??m, the best spectral resolution (without apodization) is 0.6 cm^?1, and the instantaneous field of view is 2.5°. The recording time of one spectrum is equal to 5 s in solar observations and 50 s in observations of Mars and Phobos. The instrument has self-thermal stabilization and two-axis pointing systems, as well as a built-in radiation source for flight calibration. The spectrometer mass is 4 kg, and power consumption is up to 13 W. Scientific problems, measurement modes, and, briefly, engineering implementation of the experiment are discussed in this work.  相似文献   

Stepwise Tarim Sea Retreat (West China): Eustatic VS. Tectonic Control and Links with Asian Aridification     

Guillaume DUPONT-NIVET  Roderic BOSBOOM  Arjen GROTHE  Henk BRINKHUIS  Giuliana VILLA  Oleg MANDIC  Marius STOICA  HUANG Wentao  YANG Wei  GUO ZhaoJie  Wout KRIJGSMAN 《《地质学报》英文版》2013,87(Z1):210-211

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Contributions from the 10th International Conference on Gas in Marine Sediments, Listvyanka (Russia), 6–11 September 2010     

Marc De Batist  Oleg Khlystov 《Geo-Marine Letters》2012,32(5-6):373-378

The 10th International Conference on Gas in Marine Sediments (GIMS10) took place from 6 to 11 September 2010 in Listvyanka (Russia), on the shores of Lake Baikal. The conference was organized as a double jubilee, celebrating both the fact that it was the 10th event in this series and the 20th anniversary of the series. A total of 72 oral and 47 poster presentations were given in eight thematic sessions and the presentations were discussed by 126 participants from academic, governmental and commercial institutions from 19 countries, consisting of geologists, biologists, microbiologists, geophysicists, geochemists, oceanographers and limnologists. Volume 32(5/6) of Geo-Marine Letters is a double issue containing 16 selected papers from GIMS10, and has been guest edited by M. De Batist and O. Khlystov. The papers reflect the broad-spectrum disciplines represented at the conference and cover a wide range of aspects of gas in marine sediments from many parts of the world, but with a special emphasis on the gas seeps, gas hydrates and mud volcanoes of Lake Baikal.  相似文献