Contributions of surface solar radiation and precipitation to the spatiotemporal patterns of surface and air warming in China from 1960 to 2003

Abstract. Although global warming has been attributed to increases in atmospheric greenhouses gases, the mechanisms underlying spatiotemporal patterns of warming trends remain under debate. Herein, we analyzed surface and air warming observations recorded at 1977 stations in China from 1960 to 2003. Our results showed a significant spatial pattern for the warming of the daily maximum surface (Ts-max) and air (Ta-max) temperatures, and the pattern was stronger in northwest and northeast China and weaker or negative in South China and the North China Plain. These warming spatial patterns were attributed to surface shortwave solar radiation (Rs) and precipitation (P), which play a key role in the surface energy budget. During the study period, Rs decreased by −1.50 ± 0.42 W m−2 10 yr−1 in China, which reduced the trends of Ts-max and Ta-max by about 0.139 and 0.053 °C 10 yr−1, respectively. More importantly, the decreasing rates in South China and the North China Plain were stronger than those in other parts of China. The spatial contrasts in the trends of Ts-max and Ta-max in China were significantly reduced after adjusting for the effect of Rs and P. For example, after adjusting for the effect of Rs and P, the difference in the Ts-max and Ta-max values between the North China Plain and the Loess Plateau was reduced by 97.8 and 68.3 %, respectively; the seasonal contrast in Ts-max and Ta-max decreased by 45.0 and 17.2 %, respectively; and the daily contrast in the warming rates of the surface and air temperature decreased by 33.0 and 29.1 %, respectively. This study shows that the land energy budget plays an essential role in the identification of regional warming patterns.

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Contribution of Surface Solar Radiation and Precipitation to Spatiotemporal Patterns of Surface and Air Temperature Warming in China from 1960 to 2003

10.5194/acp-2016-1022 ◽

2016 ◽

Author(s):

Jizheng Du ◽

Kaicun Wang ◽

Jiankai Wang ◽

Qian Ma

Keyword(s):

Solar Radiation ◽

Air Temperature ◽

Energy Budget ◽

South China ◽

North China Plain ◽

North China ◽

Spatiotemporal Patterns ◽

The North ◽

The North China Plain ◽

The Impact

Abstract. Although the global warming has been successfully attributed to the elevated atmospheric greenhouses gases, the reasons for spatiotemporal patterns the warming rates are still under debate. In this paper, we report surface and air warming based on observations collected at 1977 stations in China from 1960 to 2003. Our results show that the warming of daily maximum surface (Ts-max) and air (Ta-max) temperatures showed a significant spatial pattern, stronger in the northwest China and weaker in South China and the North China Plain. These warming spatial patterns are attributed to surface shortwave solar radiation (SSR) and precipitation, the key parameters of surface energy budget. During the study period, SSR decreased by −1.50 W m−2 10 yr−1 in China and caused the trends of Ts-max and Ta-max decreased by 0.139 and 0.053 °C 10 yr−1, respectively. More importantly, South China and the North China Plain had an extremely higher dimming rates than other regions. The spatial contrasts of trends of Ts-max and Ta-max in China are significantly reduced after adjusting for the impact of SSR and precipitation. For example, the difference in warming rates between North China Plain and Loess Plateau reduce by 97.8 % and 68.3 % for Ts-max and Ta-max respectively. After adjusting for the impact of SSR and precipitation, the seasonal contrast of Ts-max and Ta-max decreased by 45.0 % and 17.2 %, and the daily contrast of warming rates of surface and air temperature decreased by 33.0 % and 29.1 % over China. This study shows an essential role of land energy budget in determining regional warming.

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Surface Energy Budget Observed for Winter Wheat in the North China Plain During a Fog–Haze Event

Boundary-Layer Meteorology ◽

10.1007/s10546-018-0407-x ◽

2018 ◽

Vol 170 (3) ◽

pp. 489-505 ◽

Cited By ~ 3

Author(s):

Changwei Liu ◽

Zhiqiu Gao ◽

Yubin Li ◽

Chloe Y. Gao ◽

Zhongbo Su ◽

...

Keyword(s):

Surface Energy ◽

Winter Wheat ◽

Energy Budget ◽

North China Plain ◽

North China ◽

Surface Energy Budget ◽

The North ◽

The North China Plain ◽

Haze Event

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The combined effect of two westerly jet waveguides on heavy haze in the North China Plain in November and December 2015

10.5194/acp-2019-826 ◽

2019 ◽

Author(s):

Xiadong An ◽

Lifang Sheng ◽

Qian Liu ◽

Chun Li ◽

Yang Gao ◽

...

Keyword(s):

East Asia ◽

Rossby Wave ◽

South China ◽

North China Plain ◽

North China ◽

Combined Effect ◽

The North ◽

Westerly Jet ◽

The North China Plain ◽

Subtropical Westerly Jet

Abstract. Severe haze occurred in the North China Plain (NCP) from November to December 2015, with a wide spatial range and long duration. In this paper, the combined effect of two westerly jet waveguides on haze in the NCP was investigated based on visibility observational data and NCEP/NCAR reanalysis data. The results showed that the two Rossby waveguides within the westerly jet originating from the Mediterranean were responsible for the haze formation in the NCP. The Rossby wave propagated eastward along the subtropical westerly jet and the polar front jet, causing an anomalous anticyclone over the Sea of Japan and anticyclonic wind speed shear at 850 hPa over the NCP, which enhanced the anomalous descending air motion in the middle and lower troposphere and subsequently resulted in a stable atmosphere. Furthermore, the Rossby wave weakened the East Asia trough and Ural ridge, and strengthened the anomalous southerly wind at 850 hPa over the coastal areas of east China, decelerating the East Asia winter monsoon. The above meteorological conditions modulated haze accumulation in November and December 2015. Meanwhile, continuous rainfall related to ascending motion due to Rossby wave propagation along the subtropical westerly jet occurred in a large area of southern China. The latent heat released by rainfall acted as a heat source, inducing convection over South China. This further strengthened the ascending motion over South China so that the descending motion over the NCP was maintained, favoring the maintenance of severe haze. This study is of great significance to elucidate the formation and maintenance mechanism of large-scale haze in the NCP in late fall and boreal winter.

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Study on the Change Characteristics of and Population Exposure to Heatwave Events on the North China Plain

Advances in Meteorology ◽

10.1155/2019/7069195 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Long-Fei Zhan ◽

Yanjun Wang ◽

Hemin Sun ◽

Jianqing Zhai ◽

Mingjin Zhan

Keyword(s):

North China Plain ◽

North China ◽

Climatic Factors ◽

Demographic Data ◽

Population Exposure ◽

Central Position ◽

Daily Maximum ◽

The North ◽

The North China Plain ◽

The Impact

In accordance with the China Meteorological Administration definition, this study considered a weather process with a maximum surface temperature of ≥35°C for more than three consecutive days as a heatwave event. Based on a dataset of daily maximum temperatures from meteorological stations on the North China Plain, including ordinary and national basic/reference surface stations, the intensity-area-duration method was used to analyze the spatiotemporal distribution characteristics of heatwave events on the North China Plain (1961–2017). Moreover, based on demographic data from the Statistical Yearbook and Greenhouse Gas Initiative (GGI) Population Scenario Database of the Austrian Institute for International Applied Systems Analysis (IIASA), population exposure to heatwave events was also studied. The results showed that the frequency, intensity, and area of impact of heatwave events on the North China Plain initially decreased (becoming weaker and less extensive) and then increased (becoming stronger and more extensive). Similarly, the trend of population exposure to heatwave events initially decreased and then increased, and the central position of exposure initially moved southward and then returned northward. Population exposure in the eastern Taihang Mountains was found significantly higher than in the western Taihang Mountains. In relation to the change of population exposure to heatwave events on the North China Plain, the influence of climatic factors was found dominant with an absolute contribution rate of >75%. Except for 2011–2017, increase in population also increased the exposure to heatwaves, particularly in the first half of the study period. Interaction between climatic and population factors generally had less impact on population exposure than either climatic factors or population factors alone. This study demonstrated a method for assessing the impact of heatwave events on population exposure, which could form a scientific basis for the development of government policy regarding adaption to climate change.

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Aerosol–radiation feedback deteriorates the wintertime haze in the North China Plain

Atmospheric Chemistry and Physics ◽

10.5194/acp-19-8703-2019 ◽

2019 ◽

Vol 19 (13) ◽

pp. 8703-8719 ◽

Cited By ~ 14

Author(s):

Jiarui Wu ◽

Naifang Bei ◽

Bo Hu ◽

Suixin Liu ◽

Meng Zhou ◽

...

Keyword(s):

Solar Radiation ◽

Air Pollutants ◽

North China Plain ◽

North China ◽

Near Surface ◽

The North ◽

The North China Plain ◽

Incoming Solar Radiation ◽

Haze Pollution ◽

Pm2.5 Concentration

Abstract. Atmospheric aerosols scatter or absorb a fraction of the incoming solar radiation to cool or warm the atmosphere, decreasing surface temperature and altering atmospheric stability to further affect the dispersion of air pollutants in the planetary boundary layer (PBL). In the present study, simulations during a persistent and heavy haze pollution episode from 5 December 2015 to 4 January 2016 in the North China Plain (NCP) were performed using the Weather Research and Forecasting model with Chemistry (WRF-Chem) to comprehensively quantify contributions of aerosol shortwave radiative feedback (ARF) to near-surface (around 15 m above the ground surface) PM2.5 mass concentrations. The WRF-Chem model generally performs well in simulating the temporal variations and spatial distributions of air pollutants concentrations compared to observations at ambient monitoring sites in the NCP, and the simulated diurnal variations of aerosol species are also consistent with the measurements in Beijing. Additionally, the model simulates the aerosol radiative properties, the downward shortwave flux, and the PBL height against observations in the NCP well. During the episode, ARF deteriorates the haze pollution, increasing the near-surface PM2.5 concentrations in the NCP by 10.2 µg m−3 or with a contribution of 7.8 % on average. Sensitivity studies have revealed that high loadings of PM2.5 attenuate the incoming solar radiation reaching the surface to cool the low-level atmosphere, suppressing the development of the PBL, decreasing the surface wind speed, further hindering the PM2.5 dispersion, and consequently exacerbating the haze pollution in the NCP. Furthermore, when the near-surface PM2.5 mass concentration increases from around 50 to several hundred µg m−3, ARF contributes to the near-surface PM2.5 by more than 20 % during daytime in the NCP, substantially aggravating the heavy haze formation. However, when the near-surface PM2.5 concentration is less than around 50 µg m−3, ARF generally reduces the near-surface PM2.5 concentration due to the consequent perturbation of atmospheric dynamic fields.

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Radical chemistry at a rural site (Wangdu) in the North China Plain: Observation and model calculations of OH, HO<sub>2</sub> and RO<sub>2</sub> radicals

10.5194/acp-2016-614 ◽

2016 ◽

Cited By ~ 2

Author(s):

Zhaofeng Tan ◽

Hendrik Fuchs ◽

Keding Lu ◽

Birger Bohn ◽

Sebastian Broch ◽

...

Keyword(s):

North China Plain ◽

North China ◽

Chemical Mechanism ◽

Ozone Production ◽

Rural Site ◽

Daily Maximum ◽

Model Calculations ◽

Mixing Ratios ◽

The North ◽

The North China Plain

Abstract. A comprehensive field campaign was carried out in summer 2014 in Wangdu located in the North China Plain. A month of continuous OH, HO2 and RO2 measurements were achieved. Observations of radicals by laser induced fluorescence (LIF) technique gave daily maximum concentrations between (5–15) × 106 cm−3, (3–14) × 108 cm−3 and (3–15) × 108 cm−3 for OH, HO2 and RO2, respectively. Measured OH reactivities (inverse OH lifetimes) were 10 to 20 s−1 during daytime. A chemical box model constrained by trace-gas observations and based on a state-of-the-art chemical mechanism is used to interpret the observed radical concentrations. In general, the model can reasonably well reproduce measured radical concentrations during daytime. Like in previous field campaigns in China, modelled and measured OH concentrations agree for NO mixing ratios higher than 1 ppbv, but systematic discrepancies are observed in the afternoon for NO mixing ratios of less than 300 pptv (the model-measurement ratio is between 1.4 to 2 in this case). If additional OH recycling equivalent to 100 pptv NO is assumed, the model is also capable of reproducing the observed OH concentrations for conditions of high VOC and low NOx concentrations with good agreement in HO2 and RO2. Observed RO2 concentrations are underestimated in the morning hours by a factor of 3 to 5. This indicates that an additional chemical source of RO2 is missing in the model. The OH reactivity is also underpredicted in the early morning. Increasing VOC concentrations to match measured OH reactivity helps to reduce the discrepancy between modelled and measured RO2. The underprediction of RO2 coincides with high NO concentrations and therefore leads to a significant underestimation of the local ozone production rates determined from the peroxy radical (HO2 and RO2) reactions with NO. The underestimation corresponds to a daily integral ozone production of about 20 ppbv per day.

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High crop yield losses induced by potential HONO sources —— a case study in the North China Plain

10.21203/rs.3.rs-210489/v1 ◽

2021 ◽

Author(s):

Jingwei Zhang ◽

Haiyan Ran ◽

Yitian Guo ◽

Chaoyang Xue ◽

Xingang Liu ◽

...

Keyword(s):

Crop Yield ◽

North China Plain ◽

North China ◽

Relative Yield ◽

Daily Maximum ◽

Yield Losses ◽

Growing Seasons ◽

The North ◽

Exposure Response ◽

The North China Plain

Abstract Nitrous acid (HONO) is a major source of hydroxyl radicals in the troposphere through its photolysis, and can significantly influence ozone (O3) levels, thereby causing considerable crop yield losses. Previous studies have assessed relative crop yield losses by using exposure-response equations with observed or simulated O3, however, the contribution of enhanced O3 due to potential HONO sources to the crop yield losses has never been quantified. In this study, for the first time, we evaluated the crop yield losses caused by potential HONO sources in the North China Plain (NCP), which is one of the major grain-producing areas in China suffering from heavy O3 pollution, by using the Weather Research and Forecasting/Chemistry (WRF-Chem) model during the wheat and maize growing seasons of 2016. HONO simulations were significantly improved after including six potential HONO sources. The potential HONO sources produced a daily maximum 8-h O3 enhancement of 8.1/8.2 ppb during the wheat/maize growing seasons, respectively, and led to ~11.4%/3.3% relative yield losses for wheat/maize, respectively, corresponding to approximately US$3.78/0.66 billion losses, respectively, in NCP in 2016. Potential HONO sources play a significant role in O3 formation and may induce high crop yield losses globally.

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