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The spring land surface temperature (LST) over western Eurasia, which is critical for ensuring food security, shows a clear interannual variability. Based on reanalysis data and numerical simulations, we investigated the potential influencing factors and the related mechanisms of spring LST variability in mid-to-high latitudes of western Eurasia (MHWEA). The results show that the North Atlantic tripole sea surface temperature anomalies (SSTAs) in February, which persist into spring, can significantly affect the spring LST variability over MHWEA. Analyses indicate that the positive phase of the North Atlantic tripole SSTAs pattern tends to increase the meridional SST gradient between positive SSTAs over the midlatitude North Atlantic and negative SSTAs over the south of Greenland, which strengthens the lowlevel atmospheric baroclinicity and thus induces more active transient eddy activities. Correspondingly, a Rossby wave train triggered by the eddy-mediated processes originates from the North Atlantic and propagates downstream, thereby causing anomalous anticyclonic circulation over MHWEA. Meanwhile, the westerly anomalies over the subpolar North Atlantic accelerate the polar front jet and provide a favorable thermodynamical condition for the tropospheric warming over the Barents–Kara Seas by bringing warm and moist oceanic air. The polar warming tends to weaken the poleward temperature gradient at mid-to-high latitudes and then decelerate the Eurasian midlatitude westerlies, thus dynamically contributing to the circulation changes that can affect spring LST over MHWEA. Model results suggest that the link can be generally reproduced. Therefore, the late-winter North Atlantic tripole SSTAs may act as a precursor for the prediction of spring LST over western Eurasia. [ABSTRACT FROM AUTHOR]

School of Economics and Management, Beijing University of Technology, Beijing 100124, China Abstract In this paper, from the three dimensions of development quality, sustainable development and public satisfaction, the index system of government performance evaluation of wastewater treatment in Beijing City was constructed by conversion of critical success factor method. Using comprehensive evaluation method based on entropy weight method and principal component analysis method, the sewage treatment effect of Beijing municipal government from 2010 to 2017 was quantified, and the government's sewage treatment work was comprehensively evaluated. The evaluation results showed that the government has achieved remarkable results in sewage treatment, but it should continue to optimize the countermeasures in promoting the transformation and upgrading of economic structure, strengthening the management of urban sewage treatment and strict management system of water environment. [ABSTRACT FROM AUTHOR]

In recent years, the construction of rural sewage treatment in Beijing City has developed rapidly, but there are still many problems in some rural domestic sewage treatment. In this paper, the current situation of rural domestic sewage in Beijing City is combed, and its characteristics are summarized. Meanwhile, the current situation of rural domestic sewage treatment in Zhejiang Province, Hunan Province and Shandong Province is summarized by consulting relevant data. By comparing with current situation of rural domestic sewage treatment in Beijing City, it is found that there are some problems in the treatment of rural domestic sewage in Beijing City, such as unsuitable treatment mode, unreasonable discharge requirements and inadequate treatment technology. Therefore, some countermeasures and suggestions are proposed, such as strengthening the investigation, research and planning, and differential formulation of the sewage treatment discharge standards, and establishing modular treatment technology system. It is hoped that this paper will be helpful to the treatment of rural domestic sewage in Beijing City. [ABSTRACT FROM AUTHOR]