scholarly journals Evaluation of spatial-temporal variation performance of ERA5 precipitation data in China

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Donglai Jiao ◽  
Nannan Xu ◽  
Fan Yang ◽  
Ke Xu

AbstractERA5 is the latest fifth-generation reanalysis global atmosphere dataset from the European Centre for Medium-Range Weather Forecasts, replacing ERA-Interim as the next generation of representative satellite-observational data on the global scale. ERA5 data have been evaluated and applied in different regions, but the performances are inconsistent. Meanwhile, there are few precise evaluations of ERA5 precipitation data over long time series have been performed in Chinese mainland. This study evaluates the temporal-spatial performance of ERA5 precipitation data from 1979 to 2018 based on gridded-ground meteorological station observational data across China. The results showed that ERA5 data could capture the annual and seasonal patterns of observed precipitation in China well, with correlation coefficient values ranging from 0.796 to 0.945, but ERA5 slightly overestimated precipitation in the summer. Nonetheless, the results also showed that the accuracy of the precipitation products was strongly correlated with topographic distribution and climatic divisions. The performance of ERA5 shows spatial inherently across China that the highest correlation coefficient values locate in eastern, Northwestern and North China and the lowest biases locate in Southeast China. This study provides a reliable data assessment of the ERA5 data and precipitation trend analyses in China. The results provide accuracy references for the further use of precipitation satellite data for hydrological calculations and climate numerical simulations.

2020 ◽  
Vol 41 (S1) ◽  
pp. s459-s461
Author(s):  
Valerie M Vaughn ◽  
Lindsay A. Petty ◽  
Tejal N. Gandhi ◽  
Keith S. Kaye ◽  
Anurag Malani ◽  
...  

Background: Nearly half of hospitalized patients with bacteriuria or treated for pneumonia receive unnecessary antibiotics (noninfectious or nonbacterial syndrome such as asymptomatic bacteriuria), excess duration (antibiotics prescribed for longer than necessary), or avoidable fluoroquinolones (safer alternative available) at hospital discharge.1–3 However, whether antibiotic overuse at discharge varies between hospitals or is associated with patient outcomes remains unknown. Methods: From July 2017 to December 2018, trained abstractors at 46 Michigan hospitals collected detailed data on a sample of adult, non–intensive care, hospitalized patients with bacteriuria (positive urine culture with or without symptoms) or treated for community-acquired pneumonia (CAP; includes those with the disease formerly known as healthcare-associated pneumonia [HCAP]). Antibiotic prescriptions at discharge were assessed for antibiotic overuse using a previously described, guideline-based hierarchical algorithm.3 Here, we report the proportion of patients discharged with antibiotic overuse by the hospital. We also assessed hospital-level correlation (using Pearson’s correlation coefficient) between antibiotic overuse at discharge for patients with bacteriuria and patients treated for CAP. Finally, we assessed the association of antibiotic overuse at discharge with patient outcomes (mortality, readmission, emergency department visit, and antibiotic-associated adverse events) at 30 days using logit generalized estimating equations adjusted for patient characteristics and probability of treatment. Results: Of 17,081 patients (7,207 with bacteriuria; 9,874 treated for pneumonia), nearly half (42.2%) had antibiotic overuse at discharge (36.3% bacteriuria and 51.1% pneumonia). The percentage of patients discharged with antibiotic overuse varied 5-fold among hospitals from 14.7% (95% CI, 8.0%–25.3%) to 74.3% (95% CI, 64.2%–83.8%). Hospital rates of antibiotic overuse at discharge were strongly correlated between bacteriuria and CAP (Pearson’s correlation coefficient, 0.76; P ≤ .001) (Fig. 1). In adjusted analyses, antibiotic overuse at discharge was not associated with death, readmission, emergency department visit, or Clostridioides difficile infection. However, each day of overuse was associated with a 5% increase in the odds of patient-reported antibiotic-associated adverse events after discharge (Fig. 2). Conclusions: Antibiotic overuse at discharge was common, varied widely between hospitals, and was associated with patient harm. Furthermore, antibiotic overuse at discharge was strongly correlated between 2 disparate diseases, suggesting that prescribing culture or discharge processes—rather than disease-specific factors—contribute to overprescribing at discharge. Thus, discharge stewardship may be needed to target multiple diseases.Funding: This study was supported by the Society for Healthcare Epidemiology of America and by Blue Cross Blue Shield of Michigan and Blue Care Network.Disclosures: Valerie M. Vaughn reports contracted research for Blue Cross and Blue Shield of Michigan, the Department of VA, the NIH, the SHEA, and the APIC. She also reports receipt of funds from the Gordon and Betty Moore Foundation Speaker’s Bureau, the CDC, the Pew Research Trust, Sepsis Alliance, and the Hospital and Health System Association of Pennsylvania.


2021 ◽  
Vol 13 (11) ◽  
pp. 2081
Author(s):  
Elisa Adirosi ◽  
Mario Montopoli ◽  
Alessandro Bracci ◽  
Federico Porcù ◽  
Vincenzo Capozzi ◽  
...  

The high relevance of satellites for collecting information regarding precipitation at global scale implies the need of a continuous validation of satellite products to ensure good data quality over time and to provide feedback for updating and improving retrieval algorithms. However, validating satellite products using measurements collected by sensors at ground is still a challenging task. To date, the Dual-frequency Precipitation Radar (DPR) aboard the Core Satellite of the Global Precipitation Measurement (GPM) mission is the only active sensor able to provide, at global scale, vertical profiles of rainfall rate, radar reflectivity, and Drop Size Distribution (DSD) parameters from space. In this study, we compare near surface GPM retrievals with long time series of measurements collected by seven laser disdrometers in Italy since the launch of the GPM mission. The comparison shows limited differences in the performances of the different GPM algorithms, be they dual- or single-frequency, although in most cases, the dual-frequency algorithms present the better performances. Furthermore, the agreement between satellite and ground-based estimates depends on the considered precipitation variable. The agreement is very promising for rain rate, reflectivity factor, and the mass-weighted mean diameter (Dm), while the satellite retrievals need to be improved for the normalized gamma DSD intercept parameter (Nw).


Author(s):  
Olena Voloshkina ◽  
Olena Zhukova ◽  
Irina Korduba ◽  
Daniil Marshall

The most important component of ecologically safe development of natural and socio-economic systems is the use of nature, which involves the organization of water resources, which ensures sustainable development and for a long time retains sufficient water potential. The ХХІ century is characterized by significant negative changes in the natural environment caused by the uncontrolled use of natural resources, the development of industry and transport, which leads to increased water consumption and at the same time increase its pollution. This has been particularly noticeable over the last 50 years, when human impact on the planet's water cycle has reached a global scale. Deterioration of the ecological condition of surface waters is due to qualitative and quantitative depletion of factors of their formation, which in some cases makes it impossible to use them for economic purposes. Water quality of water bodies is formed under the influence of both natural and anthropogenic factors. As a result of human activity in reservoirs many anthropogenic substances of various degree of toxicity can arrive. The article attempts to assess changes in surface water quality over the past decade and to determine the degree of natural and man-made transformation of rivers in the region and the possibility of their self-restoration and stabilization of the ecological danger of the region. The existing methods of assessment of water bodies by chemical indicators used in the area of operation of mining enterprises are considered. In some methods, the assessment of water bodies usually reflects regional features rather than their own pollution. Calculations for the water basin river Siverskyi Donets are made and relevant patterns are established.


2020 ◽  
Vol 17 (3) ◽  
pp. 67-81
Author(s):  
Sebastian Lahajnar ◽  
Alenka Rožanec

The article explores the correlation strength of the ten most important cryptocurrencies, emphasizing the examination of differences during the periods of rising and falling prices. The daily and weekly returns of selected cryptocurrencies are taken as the basis for calculating and determining the correlation strength using the Pearson correlation coefficient. The survey covers the period from the beginning of 2017 to Bitcoin’s last local bottom in mid-March 2020. Research findings are as follows: 1) the most important cryptocurrencies are mostly moderately positively correlated with each other over time; 2) correlation strength decreases slightly during the bull period, but mostly remain in the range of moderate correlation; 3) correlation strength increases significantly during the bear period, with most cryptocurrencies strongly correlated with each other. The results do not change significantly if the daily or weekly cryptocurrency returns are used as the basis. A strong correlation in the period of falling prices prevents the effective diversification of the cryptocurrency portfolio, which must be considered when investing funds in the cryptocurrency market.


2013 ◽  
Vol 30 ◽  
pp. 89-101 ◽  
Author(s):  
Ferdy Hubers ◽  
Helen de Hoop

Dutch prescriptive grammar rules dictate that the complementizer dan ‘than’ should be used in comparative constructions of inequality. This has been an issue for grammarians from the sixteenth century onwards when als ‘as’ started to be used as an alternative form in this type of context. In order to find out why and when people choose one comparative marker over the other, we examined the use of these markers in the Spoken Dutch Corpus (CGN). We found that the use of dan is overall more common than als in comparative constructions of inequality, even though from a linguistic point of view als might be favoured. The choice between als and dan turns out to be strongly correlated with the level of education. Although this factor has been assumed to be of influence for a long time, as far as we know it has never been quantitatively tested before. We conclude that the effect of the level of education we found reflects the strong influence of the prescriptive rule taught in schools, repressing the use of als in comparatives of inequality.


2013 ◽  
Vol 94 (6) ◽  
pp. 903-914 ◽  
Author(s):  
Marion Schroedter-Homscheidt ◽  
Armel Oumbe ◽  
Angela Benedetti ◽  
Jean-Jacques Morcrette

The potential for transferring a larger share of our energy supply toward renewable energy is a widely discussed goal in society, economics, environment, and climate-related programs. For a larger share of electricity to come from fluctuating solar and wind energy-based electricity, production forecasts are required to ensure successful grid integration. Concentrating solar power holds the potential to make the fluctuating solar electricity a dispatchable resource by using both heat storage systems and solar production forecasts based on a reliable weather prediction. These solar technologies exploit the direct irradiance at the surface, which is a quantity very dependent on the aerosol extinction with values up to 100%. Results from present-day numerical weather forecasts are inadequate, as they generally use climatologies for dealing with aerosol extinction. Therefore, meteorological forecasts have to be extended by chemical weather forecasts. The paper aims at quantifying on a global scale the question of whether and where daily mean or hourly forecasts are required, or if persistence is sufficient in some regions. It assesses the performance of recently introduced NWP aerosol schemes by using the ECMWF/Monitoring Atmospheric Composition and Climate (MACC) forecast, which is a preparatory activity for the upcoming European Global Monitoring for Environment and Security (GMES) Atmosphere Service.


Climate ◽  
2019 ◽  
Vol 7 (10) ◽  
pp. 116 ◽  
Author(s):  
Nir Y. Krakauer ◽  
Tarendra Lakhankar ◽  
Ghulam H. Dars

A large population relies on water input to the Indus basin, yet basinwide precipitation amounts and trends are not well quantified. Gridded precipitation data sets covering different time periods and based on either station observations, satellite remote sensing, or reanalysis were compared with available station observations and analyzed for basinwide precipitation trends. Compared to observations, some data sets tended to greatly underestimate precipitation, while others overestimate it. Additionally, the discrepancies between data set and station precipitation showed significant time trends in such cases, suggesting that the precipitation trends of those data sets were not consistent with station data. Among the data sets considered, the station-based Global Precipitation Climatology Centre (GPCC) gridded data set showed good agreement with observations in terms of mean amount, trend, and spatial and temporal pattern. GPCC had average precipitation of about 500 mm per year over the basin and an increase in mean precipitation of about 15% between 1891 and 2016. For the more recent past, since 1958 or 1979, no significant precipitation trend was seen. Among the remote sensing based data sets, the Tropical Rainfall Measuring Mission Multi-Satellite Precipitation Analysis (TMPA) compared best to station observations and, though available for a shorter time period than station-based data sets such as GPCC, may be especially valuable for parts of the basin without station data. The reanalyses tended to have substantial biases in precipitation mean amount or trend relative to the station data. This assessment of precipitation data set quality and precipitation trends over the Indus basin may be helpful for water planning and management.


2015 ◽  
Vol 529 ◽  
pp. 1095-1115 ◽  
Author(s):  
Frederiek C. Sperna Weiland ◽  
Jasper A. Vrugt ◽  
Rens (L.) P.H. van Beek ◽  
Albrecht H. Weerts ◽  
Marc F.P. Bierkens

2013 ◽  
Vol 26 (11) ◽  
pp. 3904-3918 ◽  
Author(s):  
Seth Westra ◽  
Lisa V. Alexander ◽  
Francis W. Zwiers

Abstract This study investigates the presence of trends in annual maximum daily precipitation time series obtained from a global dataset of 8326 high-quality land-based observing stations with more than 30 years of record over the period from 1900 to 2009. Two complementary statistical techniques were adopted to evaluate the possible nonstationary behavior of these precipitation data. The first was a Mann–Kendall nonparametric trend test, and it was used to evaluate the existence of monotonic trends. The second was a nonstationary generalized extreme value analysis, and it was used to determine the strength of association between the precipitation extremes and globally averaged near-surface temperature. The outcomes are that statistically significant increasing trends can be detected at the global scale, with close to two-thirds of stations showing increases. Furthermore, there is a statistically significant association with globally averaged near-surface temperature, with the median intensity of extreme precipitation changing in proportion with changes in global mean temperature at a rate of between 5.9% and 7.7% K−1, depending on the method of analysis. This ratio was robust irrespective of record length or time period considered and was not strongly biased by the uneven global coverage of precipitation data. Finally, there is a distinct meridional variation, with the greatest sensitivity occurring in the tropics and higher latitudes and the minima around 13°S and 11°N. The greatest uncertainty was near the equator because of the limited number of sufficiently long precipitation records, and there remains an urgent need to improve data collection in this region to better constrain future changes in tropical precipitation.


2013 ◽  
Vol 84 (2) ◽  
pp. 304-309 ◽  
Author(s):  
Susan N. Al-Khateeb ◽  
Emad F. Al Maaitah ◽  
Elham S. Abu Alhaija ◽  
Serene A. Badran

ABSTRACT Objective: To assess the morphology and dimensions of mandibular symphysis (MS) in different anteroposterior jaw relationships and to investigate whether craniofacial parameters have any correlation with its shape and/or dimensions. Materials and Methods: Lateral cephalograms of subjects with Class I, Class II, and Class III skeletal relationships were traced. Several craniofacial and MS parameters were measured. MS parameters were compared between the three groups using analysis of variance and were correlated with the craniofacial parameters using the Pearson correlation coefficient. Results: Larger angle of concavity of the chin, more inclination of the alveolar bone toward the mandibular plane, and larger MS dimensions and area (P < .001) were found with a Class III skeletal relationship compared to Class I and Class II relationships. The Pearson correlation coefficient between Id-Me and AFH was r  =  0.83 and between Id-Me and LAFH it was r  =  0.81. Conclusions: The dimensions and configuration of MS in the Class III relationship were different than those in Class I and Class II relationships; the alveolar part of MS compensated for the skeletal relationship in the Class III pattern. MS dimensions were strongly correlated to anterior facial dimensions.


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