Eastern China has experienced severe and persistent winter haze episodes in recent years due to intensification of aerosol pollution. In addition to anthropogenic emissions, the winter aerosol pollution over eastern China is associated with unusual meteorological conditions, including weaker wind speeds. Here we show, based on model simulations, that during years with decreased wind speed, large decreases in dust emissions (29%) moderate the wintertime land–sea surface air temperature difference and further decrease winds by −0.06 (±0.05) m s−1 averaged over eastern China. The dust-induced lower winds enhance stagnation of air and account for about 13% of increasing aerosol concentrations over eastern China. Although recent increases in anthropogenic emissions are the main factor causing haze over eastern China, we conclude that natural emissions also exert a significant influence on the increases in wintertime aerosol concentrations, with important implications that need to be taken into account by air quality studies.

The COVID-19 outbreak greatly limited human activities and reduced primary emissions particularly from urban on-road vehicles but coincided with Beijing experiencing “pandemic haze,” raising the public concerns about the effectiveness of imposed traffic policies to improve the air quality. This paper explores the relationship between local vehicle emissions and the winter haze in Beijing before and during the COVID-19 lockdown based on an integrated analysis framework, which combines a real-time on-road emission inventory, in situ air quality observations, and a localized numerical modeling system. We found that traffic emissions decreased substantially during the COVID-19 pandemic, but its imbalanced emission abatement of NO x (76%, 125.3 Mg/day) and volatile organic compounds (VOCs, 53%, 52.9 Mg/day) led to a significant rise of atmospheric oxidants in urban areas, resulting in a modest increase in secondary aerosols due to inadequate precursors, which still offset reduced primary emissions. Moreover, the enhanced oxidizing capacity in the surrounding regions greatly increased the secondary particles with relatively abundant precursors, which was transported into Beijing and mainly responsible for the aggravated haze pollution. We recommend that mitigation policies should focus on accelerating VOC emission reduction and synchronously controlling regional sources to release the benefits of local traffic emission control.

Abstract. The ego depletion effect has been examined by over 300 independent studies during the past two decades. Despite its pervasive influence, recently this effect has been severely challenged and asserted to be a fake. Based on an up-to-date meta-analysis that examined the effectiveness of each frequently used depleting task, we preregistered the current experiment with the aim to examine whether there would be an ego depletion effect when the Stroop task is used as the depleting task. The results demonstrated a significant ego depletion effect. The current research highlights the importance of the depleting task’s effectiveness. That is to say, the “ego” could be “depleted,” but only when initial exertion is “depleting.”

In this paper, we study on the relationship between economic growth and land use and carbon emission in Nanjing from 2005 to 2014 shows that the economic growth and the carbon use of land use in Nanjing are not completely decoupled, that is, the change of land use carbon emissions with economic growth Showing an upward trend. Research proposals: Therefore, under the new normal situation of economic and social development, explore the use of low-carbon recycling economy-oriented land resource utilization and management model for the promotion of ecological civilization in Nanjing to provide new development ideas. 1 Research methods and data sources 1.1 Calculation of land use carbon emissions Land use of carbon emissions can be divided into two types，one is due to different types of land use caused by direct carbon emissions, and second, carrying human activities caused by indirect carbon emissions. The land use carbon emissions in this paper refer to direct carbon emissions, which are derived from cultivated land, other agricultural land, woodland, garden land, pasture land, construction land, water area and unused land. The land use carbon emission coefficient is affected by soil type way, farming habits and other aspects of the impact, with greater uncertainty. For the need for quantitative research, the following formula is introduced. Estimation of carbon emissions in cultivated land, woodland, garden, pasture, water and unused land : í µí±Š = ∑í µí±† í µí±– í µí±„ í µí±– (1) In Eqs.(1), W is the total amount of carbon emissions of six types of cultivated land, forest land, garden land, pasture land, water area and unused land; í µí±† í µí±– is the area of the i land type; í µí±„ í µí±– is the carbon of the ith land Emission coefficient, according to the relevant literature, the carbon emission coefficient of cultivated land is 0.40 tc/ hí µí±š 2 , and the carbon emission coefficients of garden land, forest land, grassland, water area and unused land are-0.39

Nitrogen dioxide (NO2) is a key species in studying photochemical smog and formation mechanisms of nitrate in fine particles. However, the conventional commercially available chemiluminescence (CL)‐based method often has uncertainties in measuring NO2 because of interferences with other reactive nitrogen species. In this study, an Aerodyne Cavity Attenuated Phase Shift Spectroscopy (CAPS) NO2 monitor that essentially has no interferences with nitrogen containing species was deployed in Beijing for the first time during August 2012. The CAPS NO2 monitor is highly sensitive with a detection limit (3σ) of 46.6 ppt for 1 min integration. The NO2 measured by CAPS shows overall agreement with that from CL, yet large differences up to 20% were also observed in the afternoon. Further, the discrepancies of NO2 measurements between CAPS and CL appear to be NOz dependent with larger differences at higher NOz concentrations (e.g., > 14 ppb). As a result, the ozone production efficiency of NOx (OPEx) derived from the correlations of Ox‐NOz with the CL NO2 can be overestimated by 19–37% in Beijing. The daily OPEx calculated with the CAPS NO2 ranges from 1.0 to 6.8 ppb/ppb with an average (±1σ) of 2.6 (±1.3) for the entire study. The relatively low OPEx and the relationship between OPEx and NOx suggest that ozone production chemistry is VOC sensitive during summer in Beijing. Two case studies further show that high concentrations of NOx can significantly enhance the formation of nitrate in fine particles in the presence of high O3 and favorable meteorological conditions.

Southern China experiences large year-to-year variability in the amount of winter precipitation, which can result in severe social and economic impacts. In this study, we demonstrate prediction skill of southern China winter precipitation by three operational seasonal prediction models: the operational Global seasonal forecasting system version 5 (GloSea5), the NCEP Climate Forecast System (CFSv2) and the Beijing Climate Center Climate System Model (BCC-CSM1.1m). The correlation scores reach 0.76 and 0.67 in GloSea5 and CFSv2, respectively; and the amplitude of the ensemble mean forecast signal is comparable to the observed variations. The skilful predictions in GloSea5 and CFSv2 mainly benefit from the successful representation of the observed ENSO teleconnection. El Niño weakens the Walker circulation and leads to the strengthening of the subtropical high over the northwestern Pacific. The anti-cyclone then induces anomalous northward flow over the South China Sea and brings water vapor to southern China, resulting in more precipitation. This teleconnection pattern is too weak in BCC-CSM1.1m, which explains its low skill (0.13). Whereas the most skilful forecast system is also able to simulate the influence of the Indian Ocean on southern China precipitation via changes in southwesterly winds over the Bay of Bengal. Finally, we examine the real-time forecast for 2015/16 winter when a strong El Niño event led to the highest rainfall over southern China in recent decades. We find that the GloSea5 system gave good advice as it produced the third wettest southern China in the hindcast, but underestimated the observed amplitude. This is likely due to the underestimation of the Siberian High strength in 2015/2016 winter, which has driven strong convergence over southern China. We conclude that some current seasonal forecast systems can give useful warning of impending extremes. However, there is still need for further model improvement to fully represent the complex dynamics of the region.

Stretchable ionogels have been considered as ideal materials for constructing flexible electronics. However, current ionogels suffer from the well-known trade-off between mechanical strength and conductivity. Here, we develop a simple strategy based on polymerization-induced phase separation to simultaneously enhance the mechanical performance and conductivity of the ionogels by randomly copolymerizing a hydrophobic and a hydrophilic monomer in a hydrophobic ionic liquid (IL). The polymerization process induced the formation of a bicontinuous network containing a polymer-rich phase and a solvent-rich phase. The polymer-rich domains with hydrogen bonds can bear loading, greatly improving the mechanical strength; meanwhile, the solvent-rich domains form conductive nanochannels to enhance the conductivity. The resulting copolymer ionogel is highly stretchable (500% strain), and the optimal fracture stress and conductivity are 0.29 MPa and 3.4 mS/cm, achieving 7.8- and 2.3-fold enhancements compared with that of the prepared homogeneous (pure PMEA) ionogel at the same IL content, respectively. Moreover, the ionogels also exhibit anti-swelling properties in various liquids and self-adhesiveness. Potential applications of this ionogel as a wearable sensor in a complex environment are further demonstrated.

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