المؤلفون: Sene, Kevin^Aff2

المساهمون: Sene, Kevin^Aff1

المصدر: Hydrometeorology : Forecasting and Applications. :473-499

المؤلفون: Juliette Bernard, Catherine Prigent, Carlos Jimenez, Frédéric Frappart, Cassandra Normandin, Pierre Zeiger, Yi Xi, Shushi Peng

المصدر: Frontiers in Remote Sensing, Vol 5 (2024)

مصطلحات موضوعية: remote sensing, surface water extent, wetlands, global hydrology, hydrology modeling, methane modeling, Geophysics. Cosmic physics, QC801-809, Meteorology. Climatology, QC851-999

الوصف: Inland waters, especially wetlands, play a crucial role in biodiversity, water resources and climate, and contribute significantly to global methane emissions. This study investigates the seasonal and inter-annual variability of the 0.25° × 0.25° surface water extent (SWE) from the Global Inundation Extent from Multi-Satellites (GIEMS-2) extended to a 30-year time series (1992–2020). Comparison with MODIS-derived SWE, CYGNSS-derived SWE and the Global Lakes and Wetlands Database (GLWD) shows consistent spatial patterns globally and over 10 different basins, although there are discrepancies in extent, partly due to different resolutions of the initial satellite observations. Strong cross-correlation (>0.8) in seasonal variability is observed when comparing GIEMS-2 with MODIS, CYGNSS and river discharge in most of the basins studied. Encouraging similarities were found in the inter-annual variability in most basins (cross-correlation >0.6) between GIEMS-2 and MODIS over 20 years, and between GIEMS-2 and river discharge over long time series, including over the Amazon and the Congo basins. These results highlight the reliability of GIEMS-2 in detecting changes in SWE in different environments, especially under dense vegetation, making it a valuable resource for calibrating hydrological models and studying global methane emissions.

وصف الملف: electronic resource

Relation: https://www.frontiersin.org/articles/10.3389/frsen.2024.1399234/full; https://doaj.org/toc/2673-6187

URL الوصول: https://doaj.org/article/614239abb3464b0bafedb083b83af70d

المؤلفون: Michele Magni, Edwin H. Sutanudjaja, Youchen Shen, Derek Karssenberg

المصدر: Journal of Hydroinformatics, Vol 25, Iss 5, Pp 1648-1666 (2023)

مصطلحات موضوعية: global hydrology, hybrid streamflow modelling, machine learning, post-processing, random forests, Information technology, T58.5-58.64, Environmental technology. Sanitary engineering, TD1-1066

الوصف: We present a novel hybrid framework that incorporates information from the process-based global hydrological model PCR-GLOBWB, to reduce prediction errors in streamflow simulations. In addition to catchment attributes and meteorological data, our methodology employs simulated streamflow and state variables from PCR-GLOBWB as predictors of observed river discharge. These outputs are used in a random forest, trained on a global database of streamflow measurements, to improve estimates of simulated river discharge across the globe. PCR-GLOBWB was run for the years 1979–2019 at 30 arcmin and its inputs and outputs were upscaled from daily to monthly time steps. A single random forest model was trained with these state variables, meteorological data and catchment attributes, as predictors of observed streamflow at 2,286 stations worldwide. Model performance was evaluated using Kling–Gupta efficiency (KGE). Results based on cross-validation show that the model is capable of discerning between a variety of hydroclimatic conditions and river flow dynamics, improving KGE of PCR-GLOBWB simulations at more than 80% of testing locations and increasing median KGE from −0.03 in uncalibrated runs to 0.51 after post-processing. Performance boosts are usually independent of the availability of streamflow data, making our method a potential candidate in addressing prediction in poorly gauged and ungauged basins. HIGHLIGHTS A hybrid framework for global streamflow modelling is developed, connecting PCR-GLOBWB with random forest.; The framework enables the correction of global-scale streamflow predictions with parsimonious parametrization.; Random forests improve streamflow predictions better when additionally fed with outputs from the hydrological model, as opposed to only using meteorological forcing and catchment attributes.;

وصف الملف: electronic resource

Relation: http://jhydro.iwaponline.com/content/25/5/1648; https://doaj.org/toc/1464-7141; https://doaj.org/toc/1465-1734

URL الوصول: https://doaj.org/article/ebdecca69e364f198cb406bee23e5759

المؤلفون: Yamazaki, Dai, Alsdorf, Douglas, Kim, Hyungjun, Kanae, Shinjiro, Oki, Taikan, Andreadis, Konstantinos

المصدر: 2011 IEEE International Geoscience and Remote Sensing Symposium Geoscience and Remote Sensing Symposium (IGARSS), 2011 IEEE International. :3031-3034 Jul, 2011

Relation: IGARSS 2011 - 2011 IEEE International Geoscience and Remote Sensing Symposium

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المؤلفون: Swann, Abigail LS, Hoffman, Forrest M, Koven, Charles D, Randerson, James T

المصدر: Proceedings of the National Academy of Sciences of the United States of America. 113(36)

مصطلحات موضوعية: Biological Sciences, Ecology, Earth Sciences, Plant Biology, Atmospheric Sciences, Climate Action, Asia, Atmosphere, Carbon Dioxide, Climate Change, Droughts, Ecosystem, Europe, Models, Biological, Photosynthesis, Plant Leaves, Plant Transpiration, Soil, South America, Water, drought, global warming, climate impact, evaporation, global hydrology

الوصف: Rising atmospheric CO2 will make Earth warmer, and many studies have inferred that this warming will cause droughts to become more widespread and severe. However, rising atmospheric CO2 also modifies stomatal conductance and plant water use, processes that are often are overlooked in impact analysis. We find that plant physiological responses to CO2 reduce predictions of future drought stress, and that this reduction is captured by using plant-centric rather than atmosphere-centric metrics from Earth system models (ESMs). The atmosphere-centric Palmer Drought Severity Index predicts future increases in drought stress for more than 70% of global land area. This area drops to 37% with the use of precipitation minus evapotranspiration (P-E), a measure that represents the water flux available to downstream ecosystems and humans. The two metrics yield consistent estimates of increasing stress in regions where precipitation decreases are more robust (southern North America, northeastern South America, and southern Europe). The metrics produce diverging estimates elsewhere, with P-E predicting decreasing stress across temperate Asia and central Africa. The differing sensitivity of drought metrics to radiative and physiological aspects of increasing CO2 partly explains the divergent estimates of future drought reported in recent studies. Further, use of ESM output in offline models may double-count plant feedbacks on relative humidity and other surface variables, leading to overestimates of future stress. The use of drought metrics that account for the response of plant transpiration to changing CO2, including direct use of P-E and soil moisture from ESMs, is needed to reduce uncertainties in future assessment.

وصف الملف: application/pdf

URL الوصول: https://escholarship.org/uc/item/09g7w7dp

المساهمون: Randerson, James [Univ. of California, Irvine, CA (United States). Dept. of Earth System Science]

المصدر: Proceedings of the National Academy of Sciences of the United States of America; 113; 36

وصف الملف: Medium: ED; Size: p. 10019-10024

URL الوصول: http://www.osti.gov/scitech/servlets/purl/1377477

المؤلفون: Gabriel A Cárdenas Belleza, Marc F P Bierkens, Michelle T H van Vliet

المصدر: Environmental Research Letters, Vol 18, Iss 10, p 104008 (2023)

مصطلحات موضوعية: sectoral water use, drought-heatwave events, global hydrology, water scarcity, Environmental technology. Sanitary engineering, TD1-1066, Environmental sciences, GE1-350, Science, Physics, QC1-999

الوصف: Water use for various sectors (e.g. irrigation, livestock, domestic, energy and manufacturing) is increasing due to a growing global population and economic development. Additionally, increases in frequency and severity of droughts, heatwaves and compound drought-heatwave events, also lead to responses in sectoral water use and a reduction in water availability, intensifying water scarcity. However, limited knowledge exists on the responses in sectoral water use during these hydroclimatic extremes. In this study we quantify the impacts of droughts, heatwaves and compound events on water use of irrigation, livestock, domestic, energy and manufacturing sectors at global, country and local scales. To achieve this, datasets of reported and downscaled sectoral water use (i.e. withdrawal and consumption) were evaluated during these hydroclimatic extremes and compared to normal (non-extreme) periods for 1990–2019. Our analysis shows that these hydroclimatic extremes affect water use patterns differently per sector and region. Reported data show that domestic and irrigation water use increases during heatwaves in Eastern Europe and central continental United States, while water use decreases for thermoelectric sector, particularly in Europe while it increases in north and Eastern Asia. Additionally, global water use response patterns reveal that irrigation and domestic sectors are mostly prioritized over livestock, thermoelectric and manufacturing. Reported local-scale data reveal that for most sectors and regions/locations, stronger water use responses are found for heatwaves and compound events compared to impacts during hydrological droughts. Our outcomes provide improved understanding of sectoral water use behaviour under hydroclimatic extremes. Nonetheless, given the future threats to water availability and the limited accessible information of water use, there is an urgency to collect more monitored-driven data of sectoral water use for improved assessments of water scarcity under these extremes. Consequently, this research reveals the necessity of more realistic water use models to better represent the sectoral responses to hydroclimatic extremes.

وصف الملف: electronic resource

Relation: https://doaj.org/toc/1748-9326

URL الوصول: https://doaj.org/article/03d753dfed7948a6b9946bd2e6839db4

المؤلفون: Chowdhury, Sunny^Aff19, Islam, K. M. Sajjadul^Aff19, Mohammad, Sheikh Nabil^Aff19, Amin, Md. R.^Aff19, Wahid, Choudhury^Aff20

المساهمون: Kacprzyk, Janusz, Series Editor^Aff1, Pal, Nikhil R., Advisory Editor^Aff2, Bello Perez, Rafael, Advisory Editor^Aff3, Corchado, Emilio S., Advisory Editor^Aff4, Hagras, Hani, Advisory Editor^Aff5, Kóczy, László T., Advisory Editor^Aff6, Kreinovich, Vladik, Advisory Editor^Aff7, Lin, Chin-Teng, Advisory Editor^Aff8, Lu, Jie, Advisory Editor^Aff9, Melin, Patricia, Advisory Editor^Aff10, Nedjah, Nadia, Advisory Editor^Aff11, Nguyen, Ngoc Thanh, Advisory Editor^Aff12, Wang, Jun, Advisory Editor^Aff13, Abraham, Ajith, editor^Aff14, Dutta, Paramartha, editor^Aff15, Mandal, Jyotsna Kumar, editor^Aff16, Bhattacharya, Abhishek, editor^Aff17, Dutta, Soumi, editor^Aff18

المصدر: Emerging Technologies in Data Mining and Information Security : Proceedings of IEMIS 2018, Volume 2. 813:37-47

المؤلفون: J. R. Thompson, S. N. Gosling, J. Zaherpour, C. L. R. Laizé

المصدر: Earth's Future, Vol 9, Iss 11, Pp n/a-n/a (2021)

مصطلحات موضوعية: climate change, environmental flows, river ecology, global hydrology, high flows, low flows, Environmental sciences, GE1-350, Ecology, QH540-549.5

الوصف: Abstract The hydrological characteristics of a river, including the magnitude and timing of high and low flows, are important determinants of its ecological functioning. Climate change will alter these characteristics, triggering ecological changes in river ecosystems. This study assesses risks of ecological change in 321 major river basins across the globe due to global warming relative to pre‐industrial conditions of 1.0, 1.5, 2.0 and 3.0°C. Risks associated with climate‐driven changes to high and low flows, relative to baseline (1980–2010; 0.6°C warming), are investigated using simulations from nine global hydrological models forced with climate projections from five global climate models, resulting in an ensemble of 14,445 baseline‐scenario members for each warming scenario (9 × 5 × 321). At the global‐scale, the likelihood of high risks of significant ecological change in both high and low flows increase with global warming: across all basins there is a medium‐high risk of change in high (low) flows in 21.4% (22.4%) of ensemble members for 1.0°C warming, increasing to 61.5% (63.2%) for 3.0°C. Risks are particularly pronounced for low flows at 3.0°C for many rivers in South America, southern Africa, Australia, southern Europe and central and eastern USA. Results suggest that boreal regions are least likely to see significant ecological change due to modified river flows but this may be partly the result of the exclusion of processes such as permafrost dynamics from most global hydrological models. The study highlights the ecological fragility and spatial heterogeneity of the risks that unmitigated climate change poses to global river ecosystems.

وصف الملف: electronic resource

Relation: https://doaj.org/toc/2328-4277

URL الوصول: https://doaj.org/article/ba92f6cbdd05435ab75e13cbcc663c3e