In the above article <xref ref-type="bibr" rid="ref1">1 , a difference in the definitions of our simulated reflectance (with respect to instantaneous TOA radiance) and the operational MERSI-II L1 ...reflectance (with respect to solar constant) causes errors in their direct comparisons.
Near-surface air temperature is an important indicator of climate change and extreme events. ERA5-Land reanalysis products feature finer spatial and temporal resolutions, and have been widely adopted ...in global climate-related research. However, the performance of ERA5-Land air temperature data in coastal urban agglomerations has received little attention. In this study, a comprehensive evaluation is conducted in the Guangdong−Hong Kong−Macau Greater Bay Area (GBA) using the observations of 1080 automatic weather stations in 2018 as reference. Generally, ERA5-Land underestimates temperature (an average bias of 0.90 °C), and performs better at low temperatures than at high temperatures. At the station level, it is observed that the correlation shows a strong positive linear relationship with the distance to the coastline in summer, and that the bias increases with increasing altitude throughout the year. With respect to different land cover types, data accuracy over urban and built-up lands is the lowest. The spatial pattern of ERA5-Land is generally consistent with that of stations but relatively poor in urban areas. In addition, ERA5-Land properly captures daily and monthly variations, as well as intraday temperature fluctuations. These conclusions provide a reference for the implementation of ERA5-Land in coastal urban agglomerations.
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•ERA5-Land performs better at low temperatures than at high temperatures.•Distance to the coastline and altitude affect the performance of ERA5-Land.•Data accuracy on croplands is highest, followed by forests, urban and built-up lands.•ERA5-Land is capable of capturing intraday fluctuations and seasonal variations.
Abstract Measuring the flatness error of large precision workpieces quickly and accurately is a difficult problem. A new method for preprocessing flatness measurement data based on MSE (mean squared ...error) is proposed. A mathematical model of a new data preprocessing method was established, and the mathematical formula for model solving was derived in detail. The data were measured by digital level on the plane of the granite base with dimensions of 2340 m×1540 mm. The new method and SmartLevel (basic measurement system of the level computer) were used to calculate and process the data. The flatness errors after diagonal evaluation were 4.07 μm and 3.90 μm, respectively. The relative error of the two was 4.36%, which confirmed the reliability and accuracy of the new method. The data results show that this method can be effectively used for the engineering measurement of the flatness of large precision workpieces.
Analysis in an imperfect world Wallace, Michael
Significance (Oxford, England),
February 2020, 2020-02-01, 20200201, Volume:
17, Issue:
1
Journal Article
When we observe the world, we sometimes make mistakes. Michael Wallace, on behalf of the measurement error topic group of the STRATOS Initiative, explains the potentially severe consequences of this ...often overlooked issue, and how statistics can help bring us back – or at least a little closer – to the truth
When we observe the world, we sometimes make mistakes. Michael Wallace, on behalf of the measurement error topic group of the STRATOS Initiative, explains the potentially severe consequences of this often overlooked issue, and how statistics can help bring us back – or at least a little closer – to the truth.
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