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China has made remarkable achievements in reducing carbon emissions in recent years. However, there is still much reduction room before achieving carbon neutrality. In Beijing, the capital of China, it is a strategic choice to respond to global climate change by promoting green and low-carbon development. This paper calculates the carbon dioxide emissions of key industries in Beijing and analyzes the temporal evolution trend of carbon emissions. Carbon dioxide emissions in Beijing before 2030 are predicted based on the grey prediction GM (1,1) and BP neural network model. The effects of factors of carbon dioxide emissions are discussed using the threshold regression model under different economic conditions. The results show that energy consumption intensity, GDP per capita, and the ownership of civil cars have a positive impact on carbon dioxide emissions, while the number of permanent residents and urban green space areas have a negative impact on carbon dioxide emissions. These findings of carbon emission prediction and influencing factors contribute to carbon reduction path design. Related policy implications on carbon emission reduction are put forward from the aspects of promoting industrial upgrading, accelerating the construction of advanced economic structures, optimizing transportation structures, and strengthening green building development. [ABSTRACT FROM AUTHOR]

Highlights • The increases of commuting CO 2 emissions are several times larger than the urban size, population, and economics' developments. • Metro services reducing commuting CO 2 emissions near the metro stations is not statistically significant, possibly because the proportions of car users near the metro stations are similar to the two cities' average levels, which is caused by their higher household income and the longer travel time using the metro. • In Beijing, there are the smallest commuting CO 2 emissions in the outer suburbs due to job-housing balances, short distance and large percentage of non-motorized mode uses while the largest commuting CO 2 emissions in the inner sprawl suburbs due to car trips with long distance. Abstract To understand the changing relationships between commuting CO 2 emissions (CCE), travel behavior and urban forms, this paper provides a comparative study between the typical Chinese cities of Beijing (more developed) and Xi'an (rapidly developing). Further, the effects of metro services on reducing CCE were explored, and comparative analysis on CCE between the inner sprawling suburbs and outer suburbs was conducted. It was found that: (i) the increases in CCE are several times larger than the increases in urban size, population, and economic developments; (ii) metro services reducing CCE near metro stations is not statistically significant, maybe because the proportions of car users near the metro stations are similar to the two cities' average levels, which is caused by their higher household income and the longer travel time using the metro; (iii) in Beijing, there are smallest CCE in the outer suburbs due to job-housing balances, short distance and large percentage of non-motorized mode uses while largest CCE in the inner sprawl suburbs due to car trips with long distance. These findings indicate that to cope with the rapidly increasing CCE, more attention should be paid to developing strong industry and real-estate simultaneously; the improvement in the feeder bus and public bicycle systems should also be reinforced to reduce the total travel time of metro users; and satellite cities with job-housing balance are greatly needed. The implications will benefit efforts to reduce CCE and mitigate global climate change, and they also provide empirical evidence and reference values for other global cities. [ABSTRACT FROM AUTHOR]

Urban bio-retention system is meaningful in reducing rainfall runoff and enhancing infiltration capacity. But the moisture migration in bio-retention systems are not clear under climate change. The spatial and temporal distribution of moisture under different rainfall events in bio-retention systems are studied in this paper based on experimental data in Beijing. Richards model is introduced to simulate the spatial and temporal distribution of moisture including pressure head, hydraulic head and water content under different initial and boundary conditions. As a result, we found that from the depth of the node to the lower boundary, the values of pressure head and hydraulic head increase with depth and decrease with time, while the values of water content represent opposite trends relative to the distribution of pressure head and hydraulic head in bio-retention systems. [ABSTRACT FROM AUTHOR]

The agricultural sector is extremely vulnerable to climate change and also plays a very important role in the operation of the entire economic system, leading many studies to evaluate the possible agricultural direct economic damage (ADED) of climate change. However, this damage may have an amplification impact through the intricate industrial linkages that exist among sectors, and this impact may be even greater than the original damage. Therefore, to elucidate the economic cascading effect (ECE) in China caused by ADED and industrial linkage, this paper used the ARIO model to evaluate the total ECE and analyse the differences in the 19 sectors by taking the ADED under future annual mean temperature (AMT) increases of 1–5 °C as the input condition and adjusting the exogenous parameters to enhance the adaptability of the model; the goal was to assess the economic impact of climate change in China. The results show that (i) there is a significant amplifying impact of ECE due to industrial linkage under the influence of warming, ECE will be 4.24–5.25 times that of ADED, and the total economic impact (ADED + ECE) will exceed the GDP of the Chinese capital of Beijing in 2012 when the AMT increases by 1.5 °C, while it will exceed one tenth of China's GDP when it increases by 4 °C. (ii) Manufacturing will be the sector most affected by the industrial linkage under ADED, which accounts for 26.58% of total ECE, followed by agriculture (10.39%) and construction (8.5%). (iii) The decrease in cultivated land area will have a significant impact on the economy; when it is reduced to the minimum demand (1.41% less than 2012), ADED increases by 1.65 times and ECE increases by 2.35 times. This paper aims to provide a new perspective from which to evaluate the economic impact of climate change by studying ECEs behind sectoral interactions. [ABSTRACT FROM AUTHOR]

In the acceleration of industrialization and urbanization, brownfield is an important resource for land regeneration and restoration targeting to recover its ecosystem function. Landfills, as a type of brownfield distributed in the highly populated areas, occupy massive land resources. The ecological restoration of landfills becomes an engineering approach to achieve multiple effects of society, environment, and economy. This paper aims to monitor and assess the restoration microclimatic effects of landfills restoration in China with remote sensing data and techniques. We selected representative landfill restoration projects, including Nanhaizi Park in Beijing, Nanhu Park in Tangshan, and Tianziling Park in Hangzhou, as the study cases. Using the Landsat imagery, the scenes of the pre-restoration, mid-restoration, and post-restoration were retrieved, and the surface energy balance equation was applied to calculate normalized difference vegetation index (NDVI), land surface temperature (T s), and evapotranspiration (ET), representing vegetation conditions and hydro-heat microclimate conditions. The study areas are divided into four subzones and extracted the calculated values for statistics and comparison. We defined an indicator of restoration intensity (RI) using the different subzones to the outer contour distance radius and restoration phases to evaluate the spatial-temporal restoration degrees. The spatial pattern dynamics was displayed in the urbanization context in the cases of Beijing and Tangshan. We examined and quantified the relations between RI and the key indicators, NDVI, T s , and ET. The overall results revealed that with higher restoration intensity, NDVI and ET became higher, and T s became lower. It suggested that the ecological restoration on the landfills brought better vegetation, cooling, and humidification effects for the microclimatic environment. Our research has the implications for monitoring and assessing the climatic effects of ecological restoration in the brownfield regeneration in a macroscopic and ecosystem perspective. Unlabelled Image • With satellite dataset, we developed a way to monitor vegetation and microclimatic changes in the restored landfills. • The indicator to quantify the ecological restoration intensity was invented with spatial distance and restoration phase. • Overall, with higher restoration intensity, vegetation and evapotranspiration improved, and surface temperature declined. [ABSTRACT FROM AUTHOR]