Modelling temperature extremes in the Limpopo province: bivariate time-varying threshold excess approach     

Maposa  Daniel  Seimela  Anna M.  Sigauke  Caston  Cochran  James J. 《Natural Hazards》2021,106(3):2227-2249

Natural Hazards - Aiming at the stability of a highway slope reinforced with anti-sliding piles, the mechanical behaviour of the inclined pile-soil arch in a soil slope reinforced with anti-sliding...  相似文献   

Hydrologic models coupled with 2D hydrodynamic model for high-resolution urban flood simulation     

de Arruda Gomes  Mayara Maria  de Melo Verçosa  Lívia Fragoso  Cirilo  José Almir 《Natural Hazards》2021,108(3):3121-3157

Natural Hazards - Floods are the most frequent natural disaster and pose a very challenging threat to many cities worldwide. Understanding the flood dynamic is essential for developing strategies...  相似文献   

Methodological challenges to confirmatory latent variable models of social vulnerability     

Goodman  Zachary T.  Stamatis  Caitlin A.  Stoler  Justin  Emrich  Christopher T.  Llabre  Maria M. 《Natural Hazards》2021,106(3):2731-2749

Natural Hazards - Socially vulnerable communities experience disproportionately negative outcomes following natural disasters and underscoring a need for well-validated measures to identify those...  相似文献   

Testing the consistency of Holocene and Last Glacial Maximum spatial correlations in temperature proxy records     

Maria Reschke  Igor Kröner  Thomas Laepple 《第四纪科学杂志》2021,36(1):20-28

Holocene temperature proxy records are commonly used in quantitative synthesis and model-data comparisons. However, comparing correlations between time series from records collected in proximity to one another with the expected correlations based on climate model simulations indicates either regional or noisy climate signals in Holocene temperature proxy records. In this study, we evaluate the consistency of spatial correlations present in Holocene proxy records with those found in data from the Last Glacial Maximum (LGM). Specifically, we predict correlations expected in LGM proxy records if the only difference to Holocene correlations would be due to more time uncertainty and more climate variability in the LGM. We compare this simple prediction to the actual correlation structure in the LGM proxy records. We found that time series data of ice-core stable isotope records and planktonic foraminifera Mg/Ca ratios were consistent between the Holocene and LGM periods, while time series of Uk'37 proxy records were not as we found no correlation between nearby LGM records. Our results support the finding of highly regional or noisy marine proxy records in the compilation analysed here and suggest the need for further studies on the role of climate proxies and the processes of climate signal recording and preservation.  相似文献   

A novel methodological approach for land subsidence prediction through data assimilation techniques     

Gazzola  Laura  Ferronato  Massimiliano  Frigo  Matteo  Janna  Carlo  Teatini  Pietro  Zoccarato  Claudia  Antonelli  Massimo  Corradi  Anna  Dacome  Maria Carolina  Mantica  Stefano 《Computational Geosciences》2021,25(5):1731-1750

Computational Geosciences - Anthropogenic land subsidence can be evaluated and predicted by numerical models, which are often built over deterministic analyses. However, uncertainties and...  相似文献   

International and national climate policies for aviation: a review     

Jörgen Larsson  Anna Elofsson  Thomas Sterner  Jonas Åkerman 《Climate Policy》2019,19(6):787-799

Aviation constitutes about 2.5% of all energy-related CO₂ emissions and in addition there are non-CO₂ effects. In 2016, the ICAO decided to implement a Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) and in 2017 the EU decided on faster emission reductions in its Emissions Trading System (EU ETS), which since 2012 includes the aviation sector. The effects of these policies on the expected development of air travel emissions from 2017 to 2030 have been analyzed. For the sample country Sweden, the analysis shows that when emissions reductions in other sectors are attributed to the aviation sector as a result of the EU ETS and CORSIA, carbon emissions are expected to reduce by ?0.8% per year (however if non-CO₂ emissions are included in the analysis, then emissions will increase). This is much less than what is needed to achieve the 2°C target. Our analysis of potential national aviation policy instruments shows that there are legally feasible options that could mitigate emissions in addition to the EU ETS and CORSIA. Distance-based air passenger taxes are common among EU Member States and through increased ticket prices these taxes can reduce demand for air travel and thus reduce emissions. Tax on jet fuel is an option for domestic aviation and for international aviation if bilateral agreements are concluded. A quota obligation for biofuels is a third option.

Key policy insights

• Existing international climate policies for aviation will not deliver any major emission reductions.

• Policymakers who want to significantly push the aviation sector to contribute to meeting the 2°C target need to work towards putting in place tougher international policy instruments in the long term, and simultaneously implement temporary national policy instruments in the near-term.

• Distance-based air passenger taxes, carbon taxes on jet fuel and quota obligations for biofuels are available national policy options; if they are gradually increased, and harmonized with other countries, they can help to significantly reduce emissions.

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What drives policy change for REDD+? A qualitative comparative analysis of the interplay between institutional and policy arena factors     

Kaisa Korhonen-Kurki  Maria Brockhaus  Jenniver Sehring  Monica Di Gregorio  Samuel Assembe-Mvondo  Andrea Babon 《Climate Policy》2019,19(3):315-328

Reducing Emissions from Deforestation and forest Degradation (REDD+) has emerged as a promising climate change mitigation mechanism in developing countries. In order to identify the enabling conditions for achieving progress in the implementation of an effective, efficient and equitable REDD+, this paper examines national policy settings in a comparative analysis across 13 countries with a focus on both institutional context and the actual setting of the policy arena. The evaluation of REDD+ revealed that countries across Africa, Asia and Latin America are showing some progress, but some face backlashes in realizing the necessary transformational change to tackle deforestation and forest degradation. A Qualitative Comparative Analysis (QCA) undertaken as part of the research project showed two enabling institutional configurations facilitating progress: (1) the presence of already initiated policy change; and (2) scarcity of forest resources combined with an absence of any effective forestry framework and policies. When these were analysed alongside policy arena conditions, the paper finds that the presence of powerful transformational coalitions combined with strong ownership and leadership, and performance-based funding, can both work as a strong incentive for achieving REDD+ goals.

Key policy insights

• The positive push of already existing policy change, or the negative stress of resource scarcity together with lack of effective policies, represents institutional conditions that can support REDD+ progress.

• Progress also requires the presence of powerful transformational coalitions and strong ownership and leadership. In the absence of these internal drivers, performance-based funding can work as a strong incentive.

• When comparing three assessments (2012, 2014, 2016) of REDD+ enabling conditions, some progress in establishing processes of change can be observed over time; however, the overall fluctuation in progress of most countries reveals the difficulty in changing the deforestation trajectory away from business as usual.

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A well‐established Early–Middle Pleistocene marine sequence on south‐east Zakynthos island,western Greece: Magneto‐biostratigraphic constraints and palaeoclimatic implications     

Maria D. Papanikolaou  Maria V. Triantaphyllou  Ellen S. Platzman  Philip L. Gibbard  Conall Mac Niocaill  Martin J. Head 《第四纪科学杂志》2011,26(5):523-540

The chronostratigraphy of a long, onshore Early–Middle Pleistocene marine sedimentary sequence on the south‐east part of Zakynthos island, Greece, is presented. Correlation of the succession with the isotope record of Ocean Drilling Program Site 963 reveals the combined influence of tectonics and eustacy in this area. The sequence is divided into three formations by two main unconformities that apparently relate to sea‐level lowstands associated with two major northern hemisphere glaciations, those of marine isotope stages (MIS) 22 and 12. The Zakynthos sequence in many ways is comparable with the Italian Valle di Manche section. Magnetostratigraphic and rock magnetic analyses, supported by biostratigraphy, document the position of the Matuyama/Brunhes Chron boundary (0.77 Ma), the top and base of the Jaramillo Subchron (0.99–1.07 Ma), the Cobb Mountain Subchron (1.173–1.185 Ma) and the top of the Olduvai Subchron (1.78 Ma). The underlying strata are constrained exclusively by detailed nannofossil biostratigraphy extending at least to the lowermost Pleistocene at around 2.54 Ma and therefore certainly incorporating the base of the Olduvai Subchron (1.95 Ma) and possibly the Gauss/Matuyama Chron boundary (2.58 Ma). In addition, a remarkable increase in sedimentation rate (from 3.2 and 28 cm ka^?1 to 167 cm ka^?1) and hence resolution above the Matuyama/Brunhes boundary (Middle Pleistocene) reveals one short‐lived magnetic excursion, possibly 17a (0.66 Ma), within the normal polarity Brunhes Chron. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

Cool heads for a hot world – Social sciences under a changing sky     

Arun Agrawal  Maria Carmen Lemos  Ben Orlove  Jesse Ribot 《Global Environmental Change》2012,22(2):329-331

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Mass transport triggered by heavy rainfall: the role of endorheic basins and epikarst in a regional karst aquifer          下载免费PDF全文

Maria Dolores Fidelibus  Gabriella Balacco  Andrea Gioia  Vito Iacobellis  Giuseppe Spilotro 《水文研究》2017,31(2):394-408

This study aims at recognizing the mechanisms of mass transport between the karst surface and the saturated zone in a morphostructural relief of the Mesozoic karst carbonate platform of Murgia (Puglia, Southern Italy). The large dimension of the karst aquifer, the regional scale of the flow system, the boundary condition constituted by the sea, and the lack of freshwater springs constrain to the use of wells as monitoring points and limit the study area to the recharge area comprising 986 endorheic basins. The concentrations of non‐reactive tracers (nitrates) in the waters of autogenic recharge (from endorheic basins) have been modeled through the evaluation of effective infiltration, land use, and nitrogen surplus, with reference to a time window, which includes a low precipitation period followed by significant rainfall events. The comparison between the modeled nitrate concentrations and the nitrate concentrations measured in ground waters, coupled with the analysis of groundwater chemograms and records of hydraulic heads (all referred to the same time window), allows inferring the mechanism of mass transport between the karst surface and the groundwater table. The mass transport conceptual model requires the presence of the epikarst. The infiltration of significant rainfall in the endorheic basins after a low precipitation period displaces waters stored in the epikarst toward the saturated zone. Ground waters in the post‐event period show higher concentrations of nitrates, lower concentrations of total organic carbon, and higher Mg/Ca ratios than both those of the pre‐event period and the autumn‐winter recharge period. The post‐event recharge from epikarst storage determines a transient hazard of groundwater pollution with a time lag from the occurrence of the heavy rainfall.  相似文献