The role of the land use, land use change and forestry sector in achieving Annex I reduction pledges   总被引：2，自引：2，他引：0  

Giacomo Grassi  Michel G. J. den Elzen  Andries F. Hof  Roberto Pilli  Sandro Federici 《Climatic change》2012,115(3-4):873-881

Annex I Parties may receive credits or debits from Land Use, Land Use Change and Forestry (LULUCF) activities, contributing to achieving individual emission reduction targets. In the Durban climate negotiations, Parties agreed new LULUCF accounting rules for the second commitment period of the Kyoto Protocol (CP2). By using these new rules, this paper presents key differences among Parties at the minimum (assuming no additional action) and potential (assuming additional actions) contribution of the forest-related LULUCF activities in achieving the pledges for 2020. Overall, the potential contribution of LULUCF is relatively modest (up to about 2 % of 1990 emissions) for the EU, the Annex I Parties likely joining the CP2, and for the Annex I Parties that joined the CP1 as a whole. However, for specific Parties, LULUCF can make a substantial contribution to achieving the pledges. For New Zealand, for instance, the potential contribution of future LULUCF credits may equal 33 % of its 1990 emission level. For Australia, the pledges are expressed relative to 2000 emission levels including LULUCF emissions. Given that LULUCF emissions have strongly declined between 1990 and 2000, and a further decline in foreseen by 2020 (based on Australia’s projections), the minimum contribution of LULUCF to meet the Australian pledges appears to be about 19 % and 7 % relative to its 1990 and 2000 emission level, respectively. A further 3 % potential contribution is estimated from additional actions.  相似文献   

Future regional projections of extreme temperatures in Europe: a nonstationary seasonal approach     

Maria Dolores Frías  Roberto Mínguez  Jose Manuel Gutiérrez  Fernando J. Méndez 《Climatic change》2012,113(2):371-392

This paper analyzes changes of maximum temperatures in Europe, which are evaluated using two state-of-the-art regional climate models from the EU ENSEMBLES project. Extremes are expressed in terms of return values using a time-dependent generalized extreme value (GEV) model fitted to monthly maxima. Unlike the standard GEV method, this approach allows analyzing return periods at different time scales (monthly, seasonal, annual, etc). The study focuses on the end of the 20th century (1961?C2000), used as a calibration/validation period, and assesses the changes projected for the period 2061?C2100 considering the A1B emission scenario. The performance of the regional models is evaluated for each season of the calibration period against the high-resolution gridded E-OBS dataset, showing a similar South-North gradient with larger values over the Mediterranean basin. The inter-RCM changes in the bias pattern with respect to the E-OBS are larger than the bias resulting from a change in the boundary conditions from ERA-40 to ECHAM5 20c3m. The maximum temperature response to increased green house gases, as projected by the A1B scenario, is consistent for both RCMs. Under that scenario, results indicate that the increments for extremes (e.g. 40-year return values) will be two or three times higher than those for the mean seasonal temperatures, particularly during Spring and Summer in Southern Europe.  相似文献   

Opacity effects on the polarization of line emissions in astrophysical plasmas     

Peter Hakel  Roberto C. Mancini 《Astrophysics and Space Science》2009,322(1-4):113-116

Polarization-based line spectroscopy is a valuable tool in determining the characteristics of electron distribution functions in anisotropic plasmas. For instance, directional electrons can unevenly populate the magnetic sublevels of atomic energy levels resulting in partial polarization of the emitted spectral lines. The large dimensions of astrophysical sources raise the possibility of non-negligible self-absorption effects on spectral line properties. Alternatively, the high densities characteristic of laser-produced laboratory plasmas can also result in substantial optical depth values. We present a modeling study of He-like Fe line emissions in which we investigate the effects of radiation transport on the polarization of selected spectral lines under corona conditions.  相似文献   

Integral-field high spatial resolution spectroscopy of the giant Hii region NGC5461     

Jesús López H.  Fabio Bresolin  Elena Terlevich  Roberto Terlevich  Daniel Rosa-González 《Astrophysics and Space Science》2009,324(2-4):351-354

We present preliminary results obtained from integral-field (IFU) data of the giant extragalactic Hii region NGC5461, located in a spiral arm (RA=14^h03^m41.4^s, dec=+54°19′05″) of M101. The spatial and spectral information obtained with IFUs allows us to decompose the Hii region and analyze it at high resolution.  相似文献   

New doubly-symmetric families of comet-like periodic orbits in the spatial restricted (N + 1)-body problem   总被引：1，自引：0，他引：1  

Jaume Llibre  Luci Any Roberto 《Celestial Mechanics and Dynamical Astronomy》2009,104(3):307-318

For any positive integer N ≥ 2 we prove the existence of a new family of periodic solutions for the spatial restricted (N +1)-body problem. In these solutions the infinitesimal particle is very far from the primaries. They have large inclinations and some symmetries. In fact we extend results of Howison and Meyer (J. Diff. Equ. 163:174–197, 2000) from N = 2 to any positive integer N ≥ 2.   相似文献   

Higher neutrino mass allowed if Cold Dark Matter and Dark Energy are coupled     

G. La Vacca  S.A. Bonometto  L.P.L. Colombo 《New Astronomy》2009,14(5):435-442

  相似文献   

Fluidization of buried mass-wasting deposits in lake sediments and its relevance for paleoseismology: Results from a reflection seismic study of lakes Villarrica and Calafquén (South-Central Chile)     

Jasper Moernaut  Marc De Batist  Katrien Heirman  Maarten Van Daele  Mario Pino  Robert Brümmer  Roberto Urrutia 《Sedimentary Geology》2009,213(3-4):121-135

A dense grid of very-high resolution seismic profiles on Lake Villarrica provides a quasi-3D view on intercalated lenses of low-amplitude reflections, which are connected by acoustic wipe-out patches and fractures to an underlying voluminous mass-wasting deposit. The lenses are interpreted as being created by earthquake-triggered liquefaction in this buried mass-wasting deposit and subsequent sediment fluidization and extrusion at the paleo-lake bottom. These sediment volcanoes are mapped in detail. They have a rather uniform circular geometry and show a linear relationship between apparent width and maximum thickness on a seismic section. The largest sediment volcanoes are up to 80 m wide and 1.9 m thick. Their slope angles designate a syn- to post-depositional sagging of most sediment volcanoes. Sediment volcano detection and mapping from nearby Lake Calafquén further strengthen the revealed geometrical relationships. Locally, some of the sediment/fluid escape structures extend to a higher position in the stratigraphy, which points to a polyphase escape process associated with multiple multi-century spaced strong earthquakes. Thickness and morphology of the source layer seem to exert a dominant control in the production of sediment/fluid extrusions. This study shows that reflection seismic profiling allowed recognizing 4 different seismic events in the studied stratigraphic interval, which are evidenced by mass-wasting deposits and/or fluidization features.  相似文献   

Ab initio quantum mechanical study of γ-AlOOH boehmite: structure and vibrational spectrum     

Yves Noel  Raffaella Demichelis  Fabien Pascale  Piero Ugliengo  Roberto Orlando  Roberto Dovesi 《Physics and Chemistry of Minerals》2009,36(1):47-59

The structure and vibrational spectrum of boehmite have been investigated at the quantum-mechanical level with the CRYSTAL code, using a Gaussian-type basis set and the B3LYP Hamiltonian. Three space groups are considered in this study: Cmcm, Cmc2₁, P2₁/c. Cmcm turns out to correspond to a transition state, whereas Cmc2₁ and P2₁/c are minimum energy structures. The difference among them is the position of H atoms only, the Al-O frame being essentially the same. Harmonic frequencies at the Γ point have been computed. The comparison between calculated and experimental frequencies shows a good agreement for the Al-O part of the spectrum (under 790 cm⁻¹). For the Al-OH bending modes (800–1,300 cm⁻¹) an absolute differences of 50–100 cm⁻¹ is observed; for the OH stretching modes (3,200–3,500 cm⁻¹) it increases to 120–200 cm⁻¹: anharmonicity is large because OH groups are involved in strong hydrogen bonds.  相似文献   

Monolithic or hierarchical star formation? A new statistical analysis     

Marios Kampakoglou  Roberto Trotta  Joseph Silk 《Monthly notices of the Royal Astronomical Society》2008,384(4):1414-1426

  相似文献   

Dark matter content and internal dynamics of NGC 4697: nmagic particle models from slit data and planetary nebula velocities     

Flavio De Lorenzi  Ortwin Gerhard  Roberto P. Saglia  Niranjan Sambhus  Victor P. Debattista †  Maurilio Pannella  Roberto H. Méndez 《Monthly notices of the Royal Astronomical Society》2008,385(4):1729-1748

  相似文献