ERA5-based global assessment of irrigation requirement and validation

While only 20% of harvested lands are actually irrigated, 40% of global agricultural production originates from irrigated areas. Therefore, assessing irrigation requirements is essential for the development of effective water-related policies for an efficient management of water resources. Moreover, global-scale analyses are becoming increasingly relevant, motivated by globalized production and international trade of food as well as by the need of common strategies to address climate change. In this study, a comprehensive model to estimate crop growth and irrigation requirements of 26 main crops at global scale is presented. The model computes a soil water balance using daily precipitation and reference evapotranspiration based on a high-resolution ERA5 reanalysis dataset from the European Copernicus Program. The irrigation requirement, defined as the minimum water volume to avoid water stress, is computed for year 2000 at the resolution of 5 arc-min (or 0.0833°) and aggregated at different spatial and temporal scales for relevant analyses. The estimated global irrigation requirements for 962 km3 is described in detail, also in relation to the spatial variability and to the monthly variation of the requirements. A focus on different areas of the world (California, Northern Italy and India) highlights the wealth of information provided by the model in different climatic conditions. National data of irrigation withdrawals have been used for an extensive comparison with model results. A crop-specific validation has also been made for the State of California, comparing model results with local data of irrigation volume and independent estimates of crop water use. In both cases, we found a good agreement between model results and real data.

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Scavenging in the Anthropocene: Human impact drives vertebrate scavenger species richness at a global scale

10.26686/wgtn.12469334.v1 ◽

2020 ◽

Author(s):

E Sebastián-González ◽

JM Barbosa ◽

JM Pérez-García ◽

Z Morales-Reyes ◽

F Botella ◽

...

Keyword(s):

Species Richness ◽

Human Impact ◽

Large Scale ◽

Diversity Index ◽

Global Scale ◽

Climatic Conditions ◽

Ecosystem Functions ◽

Number Of Species ◽

Terrestrial Vertebrate ◽

Latitudinal Patterns

© 2019 John Wiley & Sons Ltd Understanding the distribution of biodiversity across the Earth is one of the most challenging questions in biology. Much research has been directed at explaining the species latitudinal pattern showing that communities are richer in tropical areas; however, despite decades of research, a general consensus has not yet emerged. In addition, global biodiversity patterns are being rapidly altered by human activities. Here, we aim to describe large-scale patterns of species richness and diversity in terrestrial vertebrate scavenger (carrion-consuming) assemblages, which provide key ecosystem functions and services. We used a worldwide dataset comprising 43 sites, where vertebrate scavenger assemblages were identified using 2,485 carcasses monitored between 1991 and 2018. First, we evaluated how scavenger richness (number of species) and diversity (Shannon diversity index) varied among seasons (cold vs. warm, wet vs. dry). Then, we studied the potential effects of human impact and a set of macroecological variables related to climatic conditions on the scavenger assemblages. Vertebrate scavenger richness ranged from species-poor to species rich assemblages (4–30 species). Both scavenger richness and diversity also showed some seasonal variation. However, in general, climatic variables did not drive latitudinal patterns, as scavenger richness and diversity were not affected by temperature or rainfall. Rainfall seasonality slightly increased the number of species in the community, but its effect was weak. Instead, the human impact index included in our study was the main predictor of scavenger richness. Scavenger assemblages in highly human-impacted areas sustained the smallest number of scavenger species, suggesting human activity may be overriding other macroecological processes in shaping scavenger communities. Our results highlight the effect of human impact at a global scale. As species-rich assemblages tend to be more functional, we warn about possible reductions in ecosystem functions and the services provided by scavengers in human-dominated landscapes in the Anthropocene.

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Climatic conditions over the estuary and Firth of Forth, Scotland

Proceedings of the Royal Society of Edinburgh Section B Biological Sciences ◽

10.1017/s0269727000006710 ◽

1987 ◽

Vol 93 (3-4) ◽

pp. 245-258

Author(s):

S. J. Harrison

Keyword(s):

East Coast ◽

High Water ◽

Surface Interactions ◽

Climatic Conditions ◽

Heat Fluxes ◽

Spatial And Temporal Scales ◽

Surface Heat Fluxes ◽

Air Movement ◽

Tidal Water ◽

Firth Of Forth

SynopsisThe pattern of climatic variation over estuaries and their environs is, to a considerable extent, controlled by aspect, slope and elevation in addition to orientation of the major relief features with respect to the movement of principal weather systems. Data from the few climatological stations within the immediate vicinity of the estuary and Firth of Forth demonstrate the essentially maritime nature of climate, and indicate also that there is a dominantly west–east gradient of change in most climatological variables. Below the high water mark the movement of water in tidal ebb and flow and river inflow modify atmosphere–surface interactions over relatively short spatial and temporal scales. Observations from a fixed instrument tower on Skinflats in the middle estuary and from Inchkeith Lighthouse indicate that tidal water movements exert varying degrees of control over sub-surface heat fluxes, air movement in the atmospheric boundary layer and the inland penetration of coastal weather systems such as the typical east coast haar.

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VP07 Collaboratively Modelling The Impact Of Interventions Retrospectively

International Journal of Technology Assessment in Health Care ◽

10.1017/s026646231700304x ◽

2017 ◽

Vol 33 (S1) ◽

pp. 149-149

Author(s):

Gordon Bache ◽

Sukh Tatla ◽

Deborah Simpson

Keyword(s):

Real World ◽

Real Data ◽

System Level ◽

Local Data ◽

Real World Data ◽

Total Saving ◽

Retrospective Assessment ◽

Administration Time ◽

The Individual ◽

The Impact

INTRODUCTION:A conventional approach to communicating value is to model the budget impact of a medicine and the associated formulations in which it is available to be prescribed. However, such an approach does not demonstrate the actual realization of the proposed impact. This abstract outlines an approach to presenting retrospective data back to healthcare professionals (HCP) that blends assumptions and real-world data. For illustrative purposes, we present the results of an application of the model for subcutaneously delivered trastuzumab in an anonymized trust in Yorkshire and Humber.METHODS:The authors developed a model that examined one calendar year (from April 2014) of redistributed sales data for both the intravenous and subcutaneous formulations of trastuzumab for every National Health Service (NHS) trust in England. A series of baseline assumptions (1) were used to model the resource impact of different formulations such as chair time, HCP time, pharmacy preparation time, consumables, wastage, and other considerations. Impacts were estimated at the individual attendance level and scaled to the caseload. These baseline assumptions could then be overwritten by the individual trust using local data.RESULTS:The site delivered approximately 985 doses of subcutaneous trastuzumab over a period of 12 months from April 2014, which represented about 76 percent of the total number of doses delivered. Chair time is estimated to have reduced by 22 minutes per attendance, resulting in a total saving of 361hours. HCP administration time is estimated to have reduced by 23 minutes per attendance, resulting in a total saving of 378 hours based on changing 985 IV doses to SC therapy.CONCLUSIONS:Blending real data and assumptions to provide a retrospective assessment of actual benefits realized back to HCPs is a powerful tool for demonstrating real-world value at both an individual trust and system level.

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Assessing irrigation requirements in the Ord Sugar Industry using a simulation modelling approach

Australian Journal of Experimental Agriculture ◽

10.1071/ea98023 ◽

1998 ◽

Vol 38 (4) ◽

pp. 345 ◽

Cited By ~ 11

Author(s):

R. C. Muchow ◽

B. A. Keating

Keyword(s):

Soil Water ◽

Sugar Industry ◽

Irrigation Schedule ◽

Climatic Data ◽

Irrigation Water Requirement ◽

Irrigation Requirement ◽

Management Options ◽

Water Requirements ◽

Irrigation Requirements ◽

Modelling Approach

Summary. Sustainable irrigation guidelines that maximise profitability and minimise water losses and accession to the watertable are required for the new Ord Sugar Industry. In addition, knowledge on crop water requirements is needed to guide water allocation and costing policies for the expanding Ord Irrigation Area where sugarcane is likely to be a dominant crop. Field data indicating water requirements for sugar in the Ord Irrigation Area are few and this paper deploys a modelling approach to extrapolate from knowledge of water requirements in other parts of the world. The approach links long-term climatic data with soil water characteristics of the main soil type, with a cropping systems model, to develop indicative estimates of irrigation water requirement and yield consequences for different management options for sugarcane production in the Ord. Analyses of the growth of 12-month old ratoon crops were conducted using the APSIM–Sugarcane model with historical climatic data from 1960 to 1985 and either a deep (188 mm available water to 160 cm depth) or shallow (144 mm of water to 120 cm depth) Cununurra clay soil. Under maximum attainable growth conditions where crops were irrigated after half the soil water supply was depleted, average sucrose yield ranged from 26.7 to 29.0 t/ha, and the irrigation requirement (assuming 100% application efficiency) ranged from 22.7 to 23.8 ML/ha depending on ratooning date. Soil water holding capacity had a major effect on the number of irrigations and the interval between irrigation for a given irrigation schedule but little effect on yield or irrigation requirement. Varying the irrigation schedule by changing the level of soil water depletion before irrigation and thus the irrigation frequency, showed the tradeoff between yield and irrigation requirement with the most profitable irrigation schedule depending on the price of sucrose and the cost of irrigation relative to other costs. Most of the year-to-year variation in irrigation water requirement could be explained by the highly variable effectiveness in soil storage of rainfall which ranged from 44 to 93%. This study has provided insight and indicative estimates of the yield and irrigation requirements for different irrigation management options for use in the establishment of an Ord River sugar industry. These estimates will be further refined as field data become available.

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Facility-specific environmental footprints of wind and solar power at a global scale

10.5194/egusphere-egu2020-8139 ◽

2020 ◽

Author(s):

Joyce Bosmans ◽

Tine Dammeier ◽

Mark Huijbregts

Keyword(s):

Solar Power ◽

Ghg Emissions ◽

Global Scale ◽

Resource Scarcity ◽

Environmental Footprint ◽

Reanalysis Dataset ◽

Technological Characteristics ◽

Environmental Footprints ◽

Utility Scale ◽

Change Mitigation

Wind and solar power are vital for climate change mitigation, producing electricity at much lower greenhouse gas (GHG) emissions than conventional fossil-based technologies. Here, we obtain facility-specific environmental footprints of utility-scale wind and solar power across the globe. We investigate how the GHG footprint of wind and solar power varies across space and across technological characteristics. We will furthermore investigate other environmental footprints such as mineral resource scarcity to assess whether there is a trade-off between low GHG footprints and possibly higher other footprints.We use facility-specific technological characteristics of ~30,000 wind parks and ~10,000 photovoltaic solar parks across the globe, such as capacity, hub height, rotor diameter or type of panel, to determine the life-cycle environmental impacts per wind or solar park. The produced power per facility over its lifetime is computed based on technological characteristics as well as location-specific hourly climate input from the ERA5 reanalysis dataset. The environmental footprint is then defined as impact divided by power produced, e.g. g CO2-eq/kWh, to allow for comparison between facilities and across energy sources.The facility-specific footprints will be shown on maps to indicate spatial variability and range of footprints of both wind and solar power. We will furthermore investigate the variability in footprints using analysis of variance, in order to indicate whether climate (i.e. location-specific wind or radiation) or technological characteristics (i.e. hub height, rotor diameter or type of panel) is the main cause of variability in footprints.

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Multiregional Satellite Precipitation Products Evaluation over Complex Terrain

Journal of Hydrometeorology ◽

10.1175/jhm-d-15-0197.1 ◽

2016 ◽

Vol 17 (6) ◽

pp. 1817-1836 ◽

Cited By ~ 61

Author(s):

Yagmur Derin ◽

Emmanouil Anagnostou ◽

Alexis Berne ◽

Marco Borga ◽

Brice Boudevillain ◽

...

Keyword(s):

Rainfall Variability ◽

Tropical Rainfall Measuring Mission ◽

Global Scale ◽

Rain Gauge ◽

Swiss Alps ◽

Wet Season ◽

Reanalysis Dataset ◽

Peruvian Andes ◽

Mountainous Regions ◽

Extensive Evaluation

Abstract An extensive evaluation of nine global-scale high-resolution satellite-based rainfall (SBR) products is performed using a minimum of 6 years (within the period of 2000–13) of reference rainfall data derived from rain gauge networks in nine mountainous regions across the globe. The SBR products are compared to a recently released global reanalysis dataset from the European Centre for Medium-Range Weather Forecasts (ECMWF). The study areas include the eastern Italian Alps, the Swiss Alps, the western Black Sea of Turkey, the French Cévennes, the Peruvian Andes, the Colombian Andes, the Himalayas over Nepal, the Blue Nile in East Africa, Taiwan, and the U.S. Rocky Mountains. Evaluation is performed at annual, monthly, and daily time scales and 0.25° spatial resolution. The SBR datasets are based on the following retrieval algorithms: Tropical Rainfall Measuring Mission Multisatellite Precipitation Analysis (TMPA), the NOAA/Climate Prediction Center morphing technique (CMORPH), Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks (PERSIANN), and Global Satellite Mapping of Precipitation (GSMaP). SBR products are categorized into those that include gauge adjustment versus unadjusted. Results show that performance of SBR is highly dependent on the rainfall variability. Many SBR products usually underestimate wet season and overestimate dry season precipitation. The performance of gauge adjustment to the SBR products varies by region and depends greatly on the representativeness of the rain gauge network.

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Local singular value decomposition for signal enhancement of seismic data

Geophysics ◽

10.1190/1.2435967 ◽

2007 ◽

Vol 72 (2) ◽

pp. V59-V65 ◽

Cited By ~ 94

Author(s):

Maïza Bekara ◽

Mirko Van der Baan

Keyword(s):

Singular Value Decomposition ◽

Noise Suppression ◽

Signal To Noise Ratio ◽

Real Data ◽

Global Scale ◽

Signal Enhancement ◽

Singular Value ◽

Median Filtering ◽

Seismic Sections ◽

Value Decomposition

Singular value decomposition (SVD) is a coherency-based technique that provides both signal enhancement and noise suppression. It has been implemented in a variety of seismic applications — mostly on a global scale. In this paper, we use SVD to improve the signal-to-noise ratio of unstacked and stacked seismic sections, but apply it locally to cope with coherent events that vary with both time and offset. The local SVD technique is compared with [Formula: see text] deconvolution and median filtering on a set of synthetic and real-data sections. Local SVD is better than [Formula: see text] deconvolution and median filtering in removing background noise, but it performs less well in enhancing weak events or events with conflicting dips. Combining [Formula: see text] deconvolution or median filtering with local SVD overcomes the main weaknesses associated with each individual method and leads to the best results.

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Irrigation Requirements for Grape Crop under Climate Changes Conditions in Egypt

International Journal of Horticultural Science ◽

10.31421/ijhs/19/1-2/1079 ◽

2013 ◽

Vol 19 (1-2) ◽

Author(s):

F. A. Hashem ◽

M. K. Hassanein ◽

A. A. Khalil ◽

É. Domokos-Szabolcsy ◽

M. Fári

Keyword(s):

Climate Changes ◽

Reference Evapotranspiration ◽

Future Climate ◽

Climate Data ◽

Irrigation Requirement ◽

Negative Effects ◽

The Sustainable Development ◽

Irrigation Demand ◽

Monteith Equation ◽

Irrigation Requirements

The present work is mainly directed to discuss sensitivity of climate changes upon the irrigation demand for grape crop in Egypt. The Penman Monteith equation was used to calculate reference Evapotranspiration (ETo) under current and future climate for the two locations (El Menya and El Beheira). The historical climate data for ten years from (2000 – 2010) was used as current climate to calculate irrigation requirement for grape crop under Egyptian conditions. Two climate changes scenarios have been applied as changes in temperature. The first scenario supposed that increasing in temperature of 1.5°C would happen, and the second scenario supposed that increasing of 3.5°C would happen to calculate reference Evapotranspiration and irrigation requirement for future climate. The results showed that the evapotranspiration and irrigation requirement for grape crop at El Menya location higher than El Beheira location. Irrigation demand for grape plant under two climate changes scenario will increase in El Menya and El Beheira locations. El Menya location will take the highest irrigation demand under climate changes. Therefore, possible adaptation countermeasures should be developed to mitigate the negative effects of climate changes for the sustainable development of agro-ecosystems in Egypt.

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On Forecasting Navigation Seasons with Markov Chains

World of Transport and Transportation ◽

10.30932/1992-3252-2019-17-2-16-25 ◽

2019 ◽

Vol 17 (2) ◽

pp. 16-25

Author(s):

N. A. Filippova ◽

V. N. Bogumil ◽

V. M. Belyaev

Keyword(s):

Markov Chains ◽

Forecast Accuracy ◽

Real Data ◽

Climatic Conditions ◽

Mathematical Apparatus ◽

The North ◽

Accurate Forecast ◽

Northern Rivers ◽

Time Of Operation ◽

Ice Phenomena

The transport network in the regions of the North of theRussian Federationbasically remains seasonal (waterways, winter roads). The duration of river shipping season, depending on the climatic conditions, is 110–160 days, and the time of operation of winter roads varies within 120–210 days. Under these conditions, the accuracy of predicting the beginning and end of shipping season for the northern rivers plays a very important role. The article proposes a method for forecasting the duration of ice phenomena in the areas of shipping routes based on the use of the mathematical apparatus of Markov chains. An estimate of probability of an accurate forecast is given, taking into account the conformity with Bayes theorem and related dependencies. Verification of the method on the basis of real data proved that the forecast accuracy and probability of its implementation were sufficient for timely and effective organisation of preparatory operations for next shipping season on northern navigable rivers.

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A dynamic local scale vegetation model for lycophytes (LYCOm)

10.5194/gmd-2021-202 ◽

2021 ◽

Author(s):

Suman Halder ◽

Susanne K. M. Arens ◽

Kai Jensen ◽

Tais Wittchen Dahl ◽

Philipp Porada

Keyword(s):

Soil Carbon ◽

Vascular Plants ◽

Chemical Weathering ◽

Vascular Tissue ◽

Net Primary Production ◽

Soil Microbial Activity ◽

Global Scale ◽

Local Scale ◽

Climatic Conditions ◽

Silicate Weathering

Abstract. Lycophytes (club mosses) represent a distinct lineage of vascular plants with a long evolutionary history including numerous extant and extinct species which started out as herbaceous plants and later evolved into woody plants. They enriched the soil carbon pool through newly developed root-like structures and promoted soil microbial activity by providing organic matter. These plants enhanced soil carbon dioxide (CO2) via root respiration and also modified soil hydrology. These effects had the potential to promote the dissolution of silicate minerals, thus intensifying silicate weathering. The weathering of silicate rocks is considered one of the most significant geochemical regulators of atmospheric CO2 on a long (hundreds of thousands to millions of years) timescale. The motivation for this study is to achieve an increased understanding of the realized impacts of vascular plants, represented by modern relatives to the most basal plants with vascular tissue and shallow root system, on silicate weathering and past climate. To this end, it is necessary to quantify physiological characteristics, spatial distribution, carbon balance, and the hydrological impacts of early lycophytes. These properties, however, cannot be easily derived from proxies such as fossil records, for instance. Hence, as a first step, a process-based model is developed here to estimate net carbon uptake by these organisms at the local scale, considering key features such as biomass distribution above and below ground, root distribution in soil regulating water uptake by plants besides, stomatal regulation of water loss and photosynthesis, and not withholding respiration in roots. The model features ranges of key physiological traits of lycophytes to predict the emerging characteristics of the lycophyte community under any given climate by implicitly simulating the process of selection. In this way, also extinct plant communities can be represented. In addition to physiological properties, the model also simulates weathering rates using a simple limit-based approach and estimates the biotic enhancement of weathering by lycophytes. We run the Lycophyte model, called LYCOm, at seven sites encompassing various climate zones under today’s climatic conditions. LYCOm is able to simulate realistic properties of lycophyte communities at the respective locations and estimates values of Net Primary Production (NPP) ranging from 126 g carbon m−2 year−1 to 245 g carbon m−2 year−1. Our limit-based weathering model predicts a mean chemical weathering rate ranging from 5.3 to 45.1 cm ka−1 rock with lycophytes varying between different sites, as opposed to 0.6–8.3 cm rock ka−1 without lycophytes, thereby highlighting the potential importance of such vegetation at the local scale for enhancing chemical weathering. Our modeling study establishes a basis for assessing biotic enhancement of weathering by lycophytes at the global scale and also for the geological past. Although our method is associated with limitations and uncertainties, it represents a novel, complementary approach towards estimating the impacts of lycophytes on biogeochemistry and climate.

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