Genetic algorithms for geophysical parameter inversion from altimeter data   总被引：1，自引：0，他引：1  

Guillaume Ramillien 《Geophysical Journal International》2001,147(2):393-402

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What risks matter? Public views about assisted migration and other climate-adaptive reforestation strategies     

Guillaume Peterson St-Laurent  Shannon Hagerman  Robert Kozak 《Climatic change》2018,151(3-4):573-587

The world’s forests play an important role in regulating climate change through their capacity to sequester carbon. At the same time, they are also increasingly vulnerable to the impacts of climate change. In the western Canadian province of British Columbia, changes in temperature, precipitation, and disturbance regimes are already impacting forests. In response to these observed and anticipated changes, adapted reforestation practices are being developed and proposed as a means to help forest ecosystems adjust to changing climatic conditions. One such practice under consideration is assisted migration—planting species within or outside of the native historical range into areas that are anticipated to be climatically suitable in the future. We used a survey of British Columbia’s population at large (n?=?1923) to quantify levels of support for a range of potential reforestation options (including assisted migration) to adapt to climate change, and to explore what factors can help predict this support. Our findings reveal that the likely location of potential public controversy resides not with the potential implementation of assisted migration strategies per se, but rather with assisted migration strategies that involve movement of tree species beyond their native range.  相似文献   

Quantity Does Not Always Mean Quality: The Importance of Qualitative Social Science in Conservation Research     

Niki A. Rust  Amber Abrams  Daniel W. S. Challender  Guillaume Chapron  Arash Ghoddousi  Jenny A. Glikman 《社会与自然资源》2017,30(10):1304-1310

Qualitative methods are important to gain a deep understanding of complex problems and poorly researched areas. They can be particularly useful to help explain underlying conservation problems. However, the significance in choosing and justifying appropriate methodological frameworks in conservation studies should be given more attention to ensure data are collected and analysed appropriately. We explain when, why, and how qualitative methods should be used and explain sampling strategies in qualitative studies. To improve familiarity with qualitative methods among natural scientists, we recommend expanding training in social sciences and increasing collaboration with social scientists. Given the scale of human impacts on the environment, this type of nuanced analytical skill is critical for progressing biodiversity conservation efforts.  相似文献   

Tectono‐sedimentary evolution of the northern Iranian Plateau: insights from middle–late Miocene foreland‐basin deposits          下载免费PDF全文

Paolo Ballato  Francesca Cifelli  Ghasem Heidarzadeh  Mohammad R. Ghassemi  Andrew D. Wickert  Jamshid Hassanzadeh  Guillaume Dupont‐Nivet  Philipp Balling  Masafumi Sudo  Gerold Zeilinger  Axel K. Schmitt  Massimo Mattei  Manfred R. Strecker 《Basin Research》2017,29(4):417-446

Sedimentary basins in the interior of orogenic plateaus can provide unique insights into the early history of plateau evolution and related geodynamic processes. The northern sectors of the Iranian Plateau of the Arabia–Eurasia collision zone offer the unique possibility to study middle–late Miocene terrestrial clastic and volcaniclastic sediments that allow assessing the nascent stages of collisional plateau formation. In particular, these sedimentary archives allow investigating several debated and poorly understood issues associated with the long‐term evolution of the Iranian Plateau, including the regional spatio‐temporal characteristics of sedimentation and deformation and the mechanisms of plateau growth. We document that middle–late Miocene crustal shortening and thickening processes led to the growth of a basement‐cored range (Takab Range Complex) in the interior of the plateau. This triggered the development of a foreland‐basin (Great Pari Basin) to the east between 16.5 and 10.7 Ma. By 10.7 Ma, a fast progradation of conglomerates over the foreland strata occurred, most likely during a decrease in flexural subsidence triggered by rock uplift along an intraforeland basement‐cored range (Mahneshan Range Complex). This was in turn followed by the final incorporation of the foreland deposits into the orogenic system and ensuing compartmentalization of the formerly contiguous foreland into several intermontane basins. Overall, our data suggest that shortening and thickening processes led to the outward and vertical growth of the northern sectors of the Iranian Plateau starting from the middle Miocene. This implies that mantle‐flow processes may have had a limited contribution toward building the Iranian Plateau in NW Iran.  相似文献   

The evolution of temperature extremes in the Gaspé Peninsula,Quebec, Canada (1974–2013)     

Guillaume?FortinEmail authorView author&#;s OrcID profile  Fiorella?Acquaotta  Simona?Fratianni 《Theoretical and Applied Climatology》2017,130(1-2):163-172

The majority of natural hazards that affect Canadian territory are the result of extreme climate and weather conditions. Among these weather hazards, some can be calculated from the application of thresholds for minimum and maximum temperatures at a daily or monthly timescale. These thermal indices allowed the prediction of extreme conditions that may have an impact on the human population by affecting, for example, health, agriculture, and water resources. In this article, we discuss the methods used (RHtestsV4, SPLIDHOM, ClimPACT) then describe the steps followed to calculate the indices, including how we dealt with the problem of missing data and the necessity to identify a common methodology to analyze the time series. We also present possible solutions for ensuring the quality of meteorological data. We then present an overview of the results, namely the main trends and variability of extreme temperature for seven stations located in the Gaspé Peninsula from 1974 to 2013. Our results indicate some break points in time series and positive trends for most indices related to the rise of the temperatures but indicate a negative trend for the indices related to low temperatures for most stations during the study period.  相似文献   

Review: Impact of underground structures on the flow of urban groundwater     

Guillaume Attard  Thierry Winiarski  Yvan Rossier  Laurent Eisenlohr 《Hydrogeology Journal》2016,24(1):5-19

Property economics favours the vertical development of cities but flow of groundwater can be affected by the use of underground space in them. This review article presents the state of the art regarding the impact of disturbances caused by underground structures (tunnels, basements of buildings, deep foundations, etc.) on the groundwater flow in urban aquifers. The structures built in the underground levels of urban areas are presented and organised in terms of their impact on flow: obstacle to the flow or disturbance of the groundwater budget of the flow system. These two types of disturbance are described in relation to the structure area and the urban area. The work reviewed shows, on one hand, the individual impacts of different urban underground structures, and on the other, their cumulative impacts on flow, using real case studies. Lastly, the works are placed in perspective regarding the integration of underground structures with the aim of operational management of an urban aquifer. The literature presents deterministic numerical modelling as a tool capable of contributing to this aim, in that it helps to quantify the effect of an underground infrastructure project on groundwater flow, which is crucial for decision-making processes. It can also be an operational decision-aid tool for choosing construction techniques or for formulating strategies to manage the water resource.  相似文献   

Interannual-decadal variability of wintertime mixed layer depths in the North Pacific detected by an ensemble of ocean syntheses     

Toyoda  Takahiro  Fujii  Yosuke  Kuragano  Tsurane  Kosugi  Naohiro  Sasano  Daisuke  Kamachi  Masafumi  Ishikawa  Yoichi  Masuda  Shuhei  Sato  Kanako  Awaji  Toshiyuki  Hernandez  Fabrice  Ferry  Nicolas  Guinehut  Stéphanie  Martin  Matthew  Andrew Peterson  K.  Good  Simon A.  Valdivieso  Maria  Haines  Keith  Storto  Andrea  Masina  Simona  Köhl  Armin  Yin  Yonghong  Shi  Li  Alves  Oscar  Smith  Gregory  Chang  You-Soon  Vernieres  Guillaume  Wang  Xiaochun  Forget  Gael  Heimbach  Patrick  Wang  Ou  Fukumori  Ichiro  Lee  Tong  Zuo  Hao  Balmaseda  Magdalena 《Climate Dynamics》2017,49(3):891-907

Climate Dynamics - The interannual-decadal variability of the wintertime mixed layer depths (MLDs) over the North Pacific is investigated from an empirical orthogonal function (EOF) analysis of an...  相似文献   

Impacts of regional climate change on air quality projections and associated uncertainties     

Gwendoline Lacressonnière  Gilles Foret  Matthias Beekmann  Guillaume Siour  Magnuz Engardt  Michael Gauss  Laura Watson  Camilla Andersson  Augustin Colette  Béatrice Josse  Virginie Marécal  Agnes Nyiri  Robert Vautard 《Climatic change》2016,136(2):309-324

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Accretion disc outbursts: a new version of an old model   总被引：1，自引：0，他引：1  

Jean-Marie Hameury  Kristen Menou  Guillaume Dubus  Jean-Pierre Lasota  & Jean-Marc Huré 《Monthly notices of the Royal Astronomical Society》1998,298(4):1048-1060

We have developed 1D time-dependent numerical models of accretion discs, using an adaptive grid technique and an implicit numerical scheme, in which the disc size is allowed to vary with time. The code fully resolves the cooling and heating fronts propagating in the disc. We show that models in which the radius of the outer edge of the disc is fixed produce incorrect results, from which probably incorrect conclusions about the viscosity law have been inferred. In particular we show that outside-in outbursts are possible when a standard bimodal behaviour of the Shakura–Sunyaev viscosity parameter α is used. We also discuss to what extent insufficient grid resolution has limited the predictive power of previous models. We find that the global properties (magnitudes, etc.) of transient discs can be addressed by codes using a high, but reasonable, number of fixed grid points. However, the study of the detailed physical properties of the transition fronts generally requires resolutions which are out of reach of fixed grid codes. It appears that most time-dependent models of accretion discs published in the literature have been limited by resolution effects, improper outer boundary conditions, or both.  相似文献   

Datation par la méthode U/Th d'un travertin quaternaire du Sud-Est marocain : implications paléoclimatiques pendant le Pléistocène moyen et supérieur     

Larbi Boudad  Lahcen Kabiri  Samer Farkh  Christophe Falguères  Louis Rousseau  Jacques Beauchamp  Élisabeth Nicot  Guillaume Cairanne 《Comptes Rendus Geoscience》2003,335(5):469-478

A large travertine outcrop south of Errachidia, southern Morocco, was studied and U/Th dated. The carbonate fraction was provided by groundwaters then, as now, from the eastern High Atlas percolating through the regional Infra-Cenomanian aquifer. There were two main periods of accumulation at ca 262 kyr BP and 20–11.5 kyr BP separated by a long discontinuity with some limited weathering and erosion and correlated in part with a period of erosion at 30–20 kyr BP further to the west. The two travertine-deposition periods suggest increased rainfall and/or cooler thermal conditions in the eastern High Atlas source regions. Massive travertine accumulation ceased at the end of the Upper Pleistocene. To cite this article: L. Boudad et al., C. R. Geoscience 335 (2003).To cite this article: L. Boudad et al., C. R. Geoscience 335 (2003).  相似文献