111 research outputs found

    1961-90 HIGH RESOLUTION TEMPERATURE, PRECIPITATION, AND SOLAR RADIATION CLIMATOLOGIES FOR ITALY

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    This PhD thesis focuses on the construction of monthly 30-arc-second resolution temperature, precipitation, and solar radiation 1961-90 climatologies for Italy and on the superimposition of the information of the secular anomaly records to these climatologies. The minimum, mean, and maximum temperature climatologies are based on a quality-checked new 1961-90 dataset for Italy that includes 1,493 TM records and 1,138 TN-TX records; they have been obtained by means of a Multiple Linear Regression model, plus local and global improvements and a Geographical Inverse Distance Gaussian Weighting of the residuals. The final monthly average MAE is 0.65 \ub0C for TM, 0.91 \ub0C for TN, 0.81 \ub0C for TX. The precipitation climatologies are based on a quality-checked new 1961-90 dataset for Italy that includes more than 4,000 precipitation totals; they have been obtained by means of a PRISM model. The relative MAE for yearly total precipitation is approximately 10%. Further work is under development in order to improve both the database and the models. Examples of new reconstructed temperature and precipitation secular records for 1851-2010 are shown and the methodology used to obtain a secular record for each grid point is described. The solar radiation climatologies are obtained by means of a solar radiation model based on a quality-checked new dataset for Italy that includes more than 150 sunshine duration records. The solar radiation model is created on the basis of astronomical parameters, shading effects, albedo tables and turbidity Linke\u2019s factor: monthly 1961-90 grids for direct, diffuse, reflected, absorbed, and global radiation are obtained. The final monthly average relative MAE is 4.6%

    1961–1990 monthly high-resolution solar radiation climatologies for Italy

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    Abstract. We present a methodology for estimating solar radiation climatologies from a sparse network of global radiation and/or sunshine duration records: it allows to obtain high-resolution grids of monthly normal values for global radiation (and for the direct and diffuse components), atmospheric turbidity, and surface absorbed radiation. We discuss the application of the methodology to a preliminary version of an Italian global radiation and sunshine duration data set, which completion is still in progress and present the resulting 1961–1990 monthly radiation climatologies

    Estimating local records for Northern and Central Italy from a sparse secular temperature network and from 1961–1990 climatologies

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    The paper presents monthly 30-arc-second-resolution Northern and Central Italy temperature climatologies and discusses the procedure we adopt to superimpose the information of temperature secular records onto these climatologies. The climatologies are obtained by means of a step-wise linear regression method which aims at determining the temperature dependence on geographical and morphological variables. Such a method is applied to a database of about 800 monthly 1961–1990 temperature normals. In the first regression (temperature vs. elevation) the recorded data are considered; the further regressions concern the residuals obtained after taking into account the effect of each variable, in order of importance. An estimated secular anomaly record can be obtained for each point of the climatology grid by means of a distance-weighted average of the temperature anomaly records of the stations surrounding the grid point

    A probabilistic risk assessment of the national economic impacts of regulatory drought management on irrigated agriculture

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    Drought frequency and intensity is expected to increase in many regions worldwide, and water shortages could become more extreme, even in humid temperate climates. To protect the environment and secure water supplies, water abstraction for irrigation can be mandatorily reduced by environmental regulators. Such abstraction restrictions can result in economic impacts on irrigated agriculture. This study provides a novel approach for the probabilistic risk assessment of potential future economic losses in irrigated agriculture arising from the interaction of climate change and regulatory drought management, with an application to England and Wales. Hydro‐meteorological variability is considered within a synthetic dataset of daily rainfall and river flows for a baseline period (1977‐2004), and for projections for near (2022‐2049) and far (2072‐2099) futures. The probability, magnitude and timing of abstraction restrictions are derived by applying rainfall and river flow triggers in 129 catchments. The risk of economic losses at the catchment level is then obtained from the occurrences of abstraction restrictions combined with spatially distributed crop‐specific economic losses. Results show that restrictions will become more severe, frequent and longer in the future. The highest economic risks are projected where drought‐sensitive crops with a high financial value are concentrated in catchments with increasingly uncertain water supply. This research highlights the significant economic losses associated with mandatory drought restrictions experienced by the agricultural sector and supports the need for environmental regulators and irrigators to collaboratively manage scarce water resources to balance environmental and economic considerations

    Assessing multidomain overlaps and grand nnsemble generation in CORDEX regional projections

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    ABSTRACT: The Coordinated Regional Climate Downscaling Experiment (CORDEX) initiative has made available an enormous amount of regional climate projections in different domains worldwide. This information is crucial for the development of adaptation strategies and policy-making. A relevant open issue in this context is assessing the potential multidomain conflicts that may result in overlapping regions and developing appropriate ensemble methods trying to make the most of all available information. This work addresses this timely topic by focusing on precipitation over the Mediterranean region, a first illustrative case study that is encompassed by both the Euro- and Africa-CORDEX domains. We focus on several mean, extreme, and temporal indices and use variance decomposition to assess the separate contribution of the domain and models to the climate change signal, concluding that the contribution of the domain alone is nearly negligible (below urn:x-wiley:grl:media:grl60267:grl60267-math-0001 in all cases). Nevertheless, for some cases, the combined model/domain effect triggers up to urn:x-wiley:grl:media:grl60267:grl60267-math-0002 of the total variance.This work has been funded by the Spanish R+D Program of the Ministry of Economy and Competitiveness, through projects MULTI-SDM (CGL2015-66583-R) and INSIGNIA (CGL2016-79210-R), cofunded by the European Regional Development Fund (ERDF/FEDER)

    Extreme and long-term drought in the La Plata Basin: event evolution and impact assessment until September 2022

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    The current drought conditions across the Parana-La Plata Basin (LPB) in Brazil-Argentina have been the worst since 1944. While this area is characterized by a rainy season with a peak from October to April, the hydrological year 2020-2021 was very deficient in rainfall, and the situation extended into the 2021-2022 hydrological year. Below-normal rainfall was dominant in south-eastern Brazil, northern Argentina, Paraguay, and Uruguay, suggesting a late onset and weaker South American Monsoon and the continuation of drier conditions since 2021. In fact, in 2021 Brazilian south and south-east regions faced their worst droughts in nine decades, raising the spectre of possible power rationing given the grid dependence on hydroelectric plants. The Paraná-La Plata Basin drought induced damages to agriculture and reduced crop production, including soybeans and maize, with effects on global crop markets. The drought situation continued in 2022 in the Pantanal region. Dry meteorological conditions are still present in the region at the end of September 2022 with below-average precipitation anomalies. Soil moisture anomaly and vegetation conditions are worst in the lower part of the La Plata Basin, in the southern regions. Conversely, upper and central part of the basin show partial and temporary recovery

    Global exposure of population and land‐use to meteorological droughts under different warming levels and SSPs: a CORDEX‐based study

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    Global warming is likely to cause a progressive drought increase in some regions, but how population and natural resources will be affected is still underexplored. This study focuses on global population, forests, croplands and pastures exposure to meteorological drought hazard in the 21st century, expressed as frequency and severity of drought events. As input, we use a large ensemble of climate simulations from the Coordinated Regional Climate Downscaling Experiment (CORDEX), population projections from the NASA-SEDAC dataset and land-use projections from the Land-Use Harmonization 2 project for 1981–2100. The exposure to drought hazard is presented for five Shared Socioeconomic Pathways (SSP1-SSP5) at four Global Warming Levels (GWLs: 1.5°C to 4°C). Results show that considering only Standardized Precipitation Index (SPI; based on precipitation), the SSP3 at GWL4 projects the largest fraction of the global population (14%) to experience an increase in drought frequency and severity (versus 1981–2010), with this value increasing to 60% if temperature is considered (indirectly included in the Standardized Precipitation-Evapotranspiration Index, SPEI). With SPEI, considering the highest GWL for each SSP, 8 (for SSP2, SSP4, SSP5) and 11 (SSP3) billion people, that is, more than 90%, will be affected by at least one unprecedented drought. For SSP5 at GWL4, approximately 2 × 106^{6} km2^{2} of forests and croplands (respectively, 6% and 11%) and 1.5 × 106^{6} km2^{2} of pastures (19%) will be exposed to increased drought frequency and severity according to SPI, but for SPEI this extent will rise to 17 × 106^{6} km2^{2} of forests (49%), 6 × 106^{6} km2^{2} of pastures (78%) and 12 × 106^{6} km2^{2} of croplands (67%), being mid-latitudes the most affected. The projected likely increase of drought frequency and severity significantly increases population and land-use exposure to drought, even at low GWLs, thus extensive mitigation and adaptation efforts are needed to avoid the most severe impacts of climate change

    Drought Impact Is Alleviated in Sugar Beets (Beta vulgaris L.) by Foliar Application of Fullerenol Nanoparticles

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    Over the past few years, significant efforts have been made to decrease the effects of drought stress on plant productivity and quality. We propose that fullerenol nanoparticles (FNPs, molecular formula C-60(OH)(24)) may help alleviate drought stress by serving as an additional intercellular water supply. Specifically, FNPs are able to penetrate plant leaf and root tissues, where they bind water in various cell compartments. This hydroscopic activity suggests that FNPs could be beneficial in plants. The aim of the present study was to analyse the influence of FNPs on sugar beet plants exposed to drought stress. Our results indicate that intracellular water metabolism can be modified by foliar application of FNPs in drought exposed plants. Drought stress induced a significant increase in the compatible osmolyte proline in both the leaves and roots of control plants, but not in FNP treated plants. These results indicate that FNPs could act as intracellular binders of water, creating an additional water reserve, and enabling adaptation to drought stress. Moreover, analysis of plant antioxidant enzyme activities (CAT, APx and GPx), MDA and GSH content indicate that fullerenol foliar application could have some beneficial effect on alleviating oxidative effects of drought stress, depending on the concentration of nanoparticles applied. Although further studies are necessary to elucidate the biochemical impact of FNPs on plants; the present results could directly impact agricultural practice, where available water supplies are often a limiting factor in plant bioproductivity

    Precipitation and carbon-water coupling jointly control the interannual variability of global land gross primary production

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    Carbon uptake by terrestrial ecosystems is increasing along with the rising of atmospheric CO2 concentration. Embedded in this trend, recent studies suggested that the interannual variability (IAV) of global carbon fluxes may be dominated by semi-arid ecosystems, but the underlying mechanisms of this high variability in these specific regions are not well known. Here we derive an ensemble of gross primary production (GPP) estimates using the average of three data-driven models and eleven process-based models. These models are weighted by their spatial representativeness of the satellite-based solar-induced chlorophyll fluorescence (SIF). We then use this weighted GPP ensemble to investigate the GPP variability for different aridity regimes. We show that semi-arid regions contribute to 57% of the detrended IAV of global GPP. Moreover, in regions with higher GPP variability, GPP fluctuations are mostly controlled by precipitation and strongly coupled with evapotranspiration (ET). This higher GPP IAV in semi-arid regions is co-limited by supply (precipitation)-induced ET variability and GPP-ET coupling strength. Our results demonstrate the importance of semi-arid regions to the global terrestrial carbon cycle and posit that there will be larger GPP and ET variations in the future with changes in precipitation patterns and dryland expansion.This study by Y.Z., X.X., X.W., and J.D. is partially supported by a research grant (Project No. 2013-69002) through the USDA National Institute for Food and Agriculture (NIFA)‘s Agriculture and Food Research Initiative (AFRI), Regional Approaches for Adaptation to and Mitigation of Climate Variability and Change, and a research grant (IIA-1301789) from the National Science Foundation EPSCoR.Ye

    Loss and Damage in the Rapidly Changing Arctic

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    Arctic climate change is happening much faster than the global average. Arctic change also has global consequences, in addition to local ones. Scientific evidence shows that meltwater of Arctic sources contributes to sea-level rise significantly while accounting for 35% of current global sea-level rise. Arctic communities have to find ways to deal with rapidly changing environmental conditions that are leading to social impacts such as outmigration, similarly to the global South. International debates on Loss and Damage have not addressed the Arctic so far. We review literature to show what impacts of climate change are already visible in the Arctic, and present local cases in order to provide empirical evidence of losses and damages in the Arctic region. This evidence is particularly well presented in the context of outmigration and relocation of which we highlight examples. The review reveals a need for new governance mechanisms and institutional frameworks to tackle Loss and Damage. Finally, we discuss what implications Arctic losses and damages have for the international debate
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