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Over the past decades, human activities have directly or indirectly driven the land surface changes in eastern China. These anthropogenic forcings could trigger biochemical feedback and alter the surface biophysical properties, thus affecting local temperature. However, the latter is recognized as the "noise" and ignored when assessing historical or future climate. Here, we adopt the "observation minus reanalysis" (OMR) method to isolate the biophysical temperature footprint of multiple surface changes in eastern China over 2001–2018, using remote sensing land surface temperature and reanalysis skin temperature. A spatial regression model was used to separate the contributions from different processes. We find the biophysical feedbacks of surface changes have an annual cooling effect of −0.072 K/decade in eastern China, and the contributions from urban expansion, agricultural development, and natural vegetation greening are 0.042, −0.042, and −0.072 K/decade, correspondingly. The Northeast Plain shows agricultural activities induced cooling of −0.040 K/decade; the Loess Plateau shows natural vegetation recovery dominated cooling of −0.145 K/decade; the Huang‐Huai‐Hai Plain demonstrates a predominant urbanization warming effect of 0.124 K/decade; the Middle‐lower Yangtze shows natural vegetation greening related cooling of −0.106 K/decade. Both the intensity of the land surface changes and the temperature sensitivities drive the large spatial variability of the temperature effect. Overall, the temperature effects of surface changes are spatially heterogeneous and show considerable magnitudes. We emphasize that vegetation changes in eastern China show a strong surface cooling effect, and may contribute to the regional climate mitigation in the context of global warming. Plain Language Summary: Eastern China has experienced rapid urban expansion, agricultural expansion, and natural vegetation recovery since the 21st century. However, it is not clear to what extent land surface changes could influence local temperature through biophysical processes (i.e., changes in the proportion of solar radiation absorption and efficiency of water and heat exchange between the land surface and atmosphere). In this study, we used the "observation minus reanalysis" (OMR) method and a spatial multiple regression model to quantify the impact of these biophysical feedbacks on land surface temperature trends in eastern China from 2001 to 2018. Our findings suggest that urban expansion induced a warming effect of 0.042 K/decade on the land surface, while agricultural intensification and natural vegetation had cooling effects of −0.042 K/decade and −0.072 K/decade, respectively. The Huang‐Huai‐Hai Plain experienced a warming effect dominated by urbanization of 0.124 K/decade, while the rest of eastern China was dominated by vegetation‐related cooling. Our results reveal the significant vegetation‐based land surface cooling effect in eastern China and highlight the necessity of evaluating the climate mitigation potential of vegetation change. Key Points: Biophysical effects of multiple surface changes in eastern China cooled land surface by −0.072 K/decade from 2001 to 2018Urban expansion, agricultural development, and natural vegetation greening contributed 0.042, −0.042, and −0.072 K/decade, correspondinglyThe Huang‐Huai‐Hai Plain was dominated by urbanization‐induced warming, and vegetation‐related cooling was predominant in the rest area [ABSTRACT FROM AUTHOR]

To achieve an in-depth understanding of the aerosol optical properties in the highly-industrial region of Tangshan, we provided systematic aerosol optical properties analysis in this largest industrial zone for the first time. The aerosol optical datasets (2013.05–2015.04) and chemical component data of PM 2.5 (2014–2015) obtained from the Tangshan site of the campaign on atmospheric aerosol research (CARE-China) network were analyzed. The results showed that the Tangshan region was seriously affected by fine-mode industrial aerosols all year, which would promote the accumulation of pollutants and influence the atmospheric circulation through changing the vertical temperature gradient. The annual average aerosol optical depth (AOD) and Ångstrӧm exponent ( α ) were 0.80 ± 0.26 and 1.05 ± 0.10, respectively. The aerosol optical properties revealed significant seasonal characteristics. The maximum seasonal average AOD (1.03 ± 0.62) and α (1.12 ± 0.19) accompanied the highest seasonal secondary inorganic aerosol concentrations (SIA: SO 4 2 − , NO 3 − , NH 4 + ), 53.33 μg/m 3 , occurred in summer, and this phenomenon was attributed to the photochemical reactions favored by the high temperature and humidity. During the spring, frequent dust events led to the maximum Ca 2 + concentration of 6.57 μg/m 3 and the lowest seasonal α of 0.98 ± 0.31. Coal was used for generating heat in winter, resulting in the highest levels of pollutant emissions (Cl − , Elemental carbon (EC) and organic carbon (OC)). The aerosol type classifications showed that the industrial aerosols were the main controls in the summer and fall, representing 56%–58% of the total aerosols. While for spring and winter, mixed aerosols represented 53%–54% of the total aerosols. Hygroscopic growth effect of aerosols existed all year, which could enhance the negative radiative forcing and eventually cool the earth-atmosphere system. The classification Wing for Tangshan data showed high AOD values (> 0.70) were mainly clustered in the fine-mode growth wing and coarse-mode. Of these values, summer showed a dense AOD distribution and the highest magnitude of fine-mode AODs, with a corresponding fine particle fraction of η ~ 90% and an Rf ~ 0.20 μm. In addition, spring showed the most coarse-mode aerosols. [ABSTRACT FROM AUTHOR]