A preliminary study of cryosphere service function and value evaluation

Cryosphere science research and development(R&D) has been strongly committed to public service, integrating natural sciences with socioeconomic impacts. Owing to the current shift from purely natural cryosphere scientific research to linking cryosphere science with socioeconomic and cultural science, cross-disciplinary research in this field is emerging, which advocates future cryosphere science research in this field. Utilizing the cryosphere service function(CSF), this study establishes CSF and its value evaluation system. Cryosphere service valuation can benefit the decisionmakers' and public's awareness of environmental protection. Implementing sustainable CSF utilization strategies and macroeconomic policymaking for global environmental protection will have profound and practical significance as well as avoid environmental degradation while pursuing short-term economic profits and achieving rapid economic development.

Analysis on energy demand and CO2 emissions in China following the Energy Production and Consumption Revolution Strategy and China Dream target

A quantitative model was applied to analyze the energy demand and CO2 emissions in China following the Energy Production and Consumption Revolution Strategy(2016e2030)and long-term economic and social development target China Dream.Results showed that 1)toward the 2050 China Dream target,total final energy consumption is expected to peak at 3.9 Gtce in 2030 and remain stable until 2050,whereas total primary energy consumption is expected to reach an upper platform by 2040 and around 5.8 Gtce by 2050;2)the proportion of non-fossil fuels is expected to reach approximately 50%and that of natural gas to reach more than 16%by 2050;3)CO2 emissions from energy use are expected to peak at 9.6 Gt by no later than 2030 and then gradually decline to 6.7 Gt by 2050.

Modeling an emissions peak in China around 2030: Synergies or trade-offs between economy, energy and climate security

China has achieved a political consensus around the need to transform the path of economic growth toward one that lowers carbon intensity and ultimately leads to reductions in carbon emissions,but there remain different views on pathways that could achieve such a transformation.The essential question is whether radical or incremental reforms are required in the coming decades.This study explores relevant pathways in China beyond 2020,particularly modeling the major target choices of carbon emission peaking in China around 2030 as China-US Joint Announcement by an integrated assessment model for climate change IAMC based on carbon factor theory.Here scenarios DGS-2020,LGS2025,LBS-2030 and DBS-2040 derived from the historical pathways of developed countries are developed to access the comprehensive impacts on the economy,energy and climate security for the greener development in China.The findings suggest that the period of 2025e2030 is the window of opportunity to achieve a peak in carbon emissions at a level below 12 Gt CO2and 8.5 t per capita by reasonable trade-offs from economy growth,annually 0.2%in average and cumulatively 3%deviation to BAU in 2030.The oil and natural gas import dependence will exceed 70%and 45%respectively while the non-fossil energy and electricity share will rise to above 20%and 45%.Meantime,the electrification level in end use sectors will increase substantially and the electricity energy ratio approaching 50%,the labor and capital productivity should be double in improvements and the carbon intensity drop by 65%by 2030 compared to the 2005 level,and the cumulative emission reductions are estimated to be more than 20 Gt CO2in 2015e2030.

Analysis on Changes of Basic Climatic Elements and Extreme Events in Xinjiang, China during 1961-2010

By using the observation data from 89 weather stations in Xinjiang during 1961-2010, this paper analyzed the basic climatic elements including temperature, precipitation, wind speed, sunshine duration, water vapor pressure, and dust storm in the entire Xinjiang and the subareas: North Xinjiang, Tianshan Mountains, and South Xinjiang. The results indicate that from 1961 to 2010 the annual and seasonal mean temperatures in the entire Xinjiang show an increasing trend with the increasing rate rising from south to north. The increasing rate of annual mean minimum temperature is over twice more than that of the annual mean maximum temperature, contributing much to the increase in the annual averages. The magnitude of the decrease rate of low-temperature days is larger than the increase rate of high-temperature days. The increase of warm days and warm nights and the decrease of cold days and cold nights further reveal that the temperature increasing in Xinjiang is higher. In addition, annual and seasonal rainfalls have been increasing. South Xinjiang experiences higher increase in rainfall amounts than North Xinjiang and Tianshan Mountains. Annual rainy days, longest consecutive rainy days, the daily maximum precipitation and extreme precipitation events, annual torrential rain days and amount, annual blizzard days and amount, all show an increasing trend, corresponding to the increasing in annual mean water vapor pressure. This result shows that the humidity has increased with temperature increasing in the past 50 years. The decrease in annual mean wind speed and gale days lessen the impact of dust storm, sandstorm, and floating dust events. The increase in annual rainy days is the cause of the decrease in annual sunshine duration, while the increase in spring sunshine duration corresponds with the decrease in dust weather. Therefore, the increase in precipitation indicators, the decrease in gales and dust weather, and the increasing in sunshine duration in spring will be beneficial to crops growth.

Review of recent studies of the climatic effects of urbanization in China

This paper summarizes recent studies on the effects of urbanization on climate in China. The effects of urbanization on local climate trends have been re-estimated based on homogenized observations and using improved methods. In this respect, the effect of urbanization on the observed warming trend of local surface air temperatures during the last few decades is determined as being about 20% at urban stations such as the Beijing Observatory. The large-scale weakening trend of wind speed is also about 20% more prominent at the city center than its surroundings. The effect of urbanization on precipitation is not profound, but results of high-resolution regional climate modeling suggest that this effect may depend on the urban extent. Although the urban heat island(UHI) should favor local atmospheric convection and hence precipitation, the increasingly extending urban land-use may reduce precipitation over the urban cluster in North China. It is found that urbanization can play a more notable role in extreme events than usual weather. High-resolution simulations show a positive feedback between the UHI and the super-heat wave in Shanghai during Julye August 2013. Relevant studies dealing with urban climate adaptation are discussed in relation to recent ?ndings.

Development as adaptation: Framing and measuring urban resilience in Beijing

As part of their efforts to cope with climate change, many municipal governments have considered the improvement of urban resilience as an important strategy. In this study, we take the megacity of Beijing as an example and conduct a mixed-methods research using both qualitative and quantitative methods to explore linkage between resilience and development. First, based on expert consultation, we develop an analytical framework and propose reference indicators for measuring urban resilience. Second, we conduct an exploratory factor analysis to justify this analytical framework and rank the urban resilience index for 16 districts in Beijing. Results indicate that urban resilience at the district level is distinguished by the characteristics of the district's functional zones. This implies that the development focus of each district influences the driving factors of urban resilience. This article provides evidence that development and adaptation can be complementary. We showcase in Beijing that urban generic resilience is highly dependent on socio-economic development and urbanization, whereas specific resilience to climatic extremes can be attributed to natural endowment and environmental investment. In conclusion, using this study's findings as a guideline, mega-cities are urged to adopt development-oriented adaptation as a strategy of proactive risk planning in the context of rapid urbanization and global climate change in China.

Surface Air Temperature Simulations over China with CMIP5 and CMIP3

Historical simulations of annual mean surface air temperature over China with 25 CMIP5 models were assessed.The observational data from CRUT3v and CN05 were used and further compared with historical simulations of CMIP3.The results show that CMIP5 models were able to simulate the observed warming over China from 1906 to 2005(0.84 C per 100 years)with a warming rate of 0.77 C per 100 years based on the multi-model ensemble(MME).The simulations of surface air temperature in the late 20th century were much better than those in the early 20th century,when only two models could reproduce the extreme warming in the 1940s.The simulations for the spatial distribution of the 20-yearmean(1986–2005)surface air temperature over China fit relatively well with the observations.However,underestimations in surface air temperature climatology were still found almost all over China,and the largest cold bias and simulation uncertainty were found in western China.On sub-regional scale,northern China experienced stronger warming than southern China during 1961–1999,for which the CMIP5 MME provided better simulations.With CMIP5 the diference of warming trends in northern and southern China was underestimated.In general,the CMIP5 simulations are obviously improved in comparison with the CMIP3 simulations in terms of the variation in regional mean surface air temperature,the spatial distribution of surface air temperature climatology and the linear trends in surface air temperature all over China.

A new look at roles of the cryosphere in sustainable development

While the cryosphere may bring in adverse impacts on natural and built environment, it may also provide benefits resulting from cryosphere services. By looking into the effect of the cryosphere on human-being, the study develops a unified approach in the analysis of cryospheric risks and services, with one focusing on the adverse impacts by cryospheric hazards and another emphasizing on the benefits that people can obtain from the natural capitals in the cryosphere. Meanwhile, climate change could further alter and complicate the roles of the cryosphere, not only by the changes in risks to cryospheric hazards, but also the changes in services that could potentially add more risks. The study further proposed a risk-based approach for the development of climate adaptation in the cryosphere. The approach essentially takes options to reduce exposure and vulnerability of societies to cryospheric hazards, and to better manage natural capitals and demands together with enhancing utility of the cryosphere, so as to maintain the benefit of cryosphere services in a sustainable way. The study further addresses the role of cryosphere services in strengthening sustainable development in terms of its relation with the sustainable development goals (SDGs), and provides a preliminary results on how the services contributes to SDGs. Overall, the approach developed in this study creates a new way to comprehensively assess the effect of cryosphere changes on our society and identify measures to maximize the benefit while minimizing the risk in relation to the cryosphere.

Introduction of CMIP5 Experiments Carried out with the Climate System Models of Beijing Climate Center

The climate system models from Beijing Climate Center, BCC_CSM1.1 and BCC_CSM1.1-M, are used to carry out most of the CMIP5 experiments. This study gives a general introduction of these two models, and provides main information on the experiments including the experiment purpose, design, and the external forcings. The transient climate responses to the CO2 concentration increase at 1% per year are presented in the simulation of the two models. The BCC_CSM1.1-M result is closer to the CMIP5 multiple models ensemble. The two models perform well in simulating the historical evolution of the surface air temperature, globally and averaged for China. Both models overestimate the global warming and underestimate the warming over China in the 20th century. With higher horizontal resolution, the BCC_CSM1.1-M has a better capability in reproducing the annual evolution of surface air temperature over China.

Moisture sources of extreme summer precipitation events in North Xinjiang and their relationship with atmospheric circul

In this study, the daily observational precipitation data and NCEP reanalysis data during 1951e2014, Euler and Lagrangian method were used to investigate the moisture sources of summer extreme precipitation events in North Xinjiang. The results show that water vapor at low and upper levels of most summer heavy rain (more than 50 mm d
1 and less than 100 mm d
1) in North Xinjiang are mainly transported by westerly circulation from the North Atlantic Ocean and the Eurasian continent. However, rainstorms of more than 100 mm d
1, which are rarely observed, are dominated by vertically integrated moisture from the North Atlantic, Arctic Oceans, and the Eurasian continent, in addition to lowlevel moisture from the Indian Ocean. Among these sources, the anomalous low-level moisture from the Indian Ocean, which is closely associated with stronger meridional circulation, is considered to be more important with respect to rainstorms. On the days prior to rainstorm days, stronger meridional circulation leads to an anomalous pressure gradient force, which can transport low-level moisture from the Indian Ocean along the eastern periphery of the Tibetan Plateau to North Xinjiang. Furthermore, moisture from the North Atlantic, Arctic Oceans, the Eurasian continent, and the Indian Ocean converge together to influence rainstorm development in this region.

Carbon emission scenarios of China's power sector:Impact of controlling measures and carbon pricing mechanism

The study constructs a low-carbon path analysis model of China's power sector based on TIMES model and presents a comparative analysis of carbon emissions under Reference,Low-Carbon and Enhanced Low-Carbon scenarios,and the main difference of the three scenarios is manifested by policy selection and policy strength.The conclusions are drawn as follows:(1)The peak of carbon emission in China's power sector will range from 4.0 GtCO2 to 4.8 GtCO2,which implies an increment of 0.5e1.3 billion or 14%e35%from the 2015 levels.(2)Introducing carbon price is an effective way to inhibit coal power and promote non-fossil fuels and Carbon Capture,Utilization and Storage applications(CCUS).The carbon emission reduction effects will gradually increase with carbon price.When the carbon price attains to CN￥150 t
1CO2,the CO2 emission can decrease by 36%than that without carbon price.(3)CCUS is one of important contributing factor to reduce CO2 emission in power sector.Generally speaking,the development of non-fossil fuels and energy efficiency improvement are two main drivers for carbon mitigation,but once the carbon price reaches up to CN￥106 t
1CO2,the CCUS will be required to equip with thermal power units and its contribution on carbon emission reduction will remarkably increase.When carbon price increases to CN￥150 t
1CO2 in 2050,the application of CCUS will account for 44%of total emission reduction.(4)In the scenario with carbon price of CN￥150 t
1CO2,power sector would be decarbonized significantly,and the CO2 intensity will be 0.22 kgCO2(kW h)
1,but power sector is far from the goal that achieving net zero emission.In order to realize the long-term low greenhouse gas emission development goal that proposed by the Paris Agreement,more efforts are needed to be put to further reduce the carbon emission reduction of power sector.Based on the above scenario analysis,the study proposes four recommendations on the low-carbon development of China's power sector:(1)improve the energy efficiency proactively and optimize the energy structure of power sector gradually;(2)promote the low-carbon transition of power sector by using market-based mechanism like carbon emission trading scheme to internalize the external cost of carbon emission;(3)give more emphasis on and support to the CCUS application in power sector.

Natural and human-induced changes in summer climate over the East Asian monsoon region in the last half century: A review

In the last half century,a significant warming trend occurred in summer over eastern China in the East Asian monsoon region.However,there were no consistent trends with respect to the intensity of the East Asian summer monsoon(EASM) or the amount of summer rainfall averaged over eastern China.Both of the EASM and summer rainfall exhibited clear decadal variations.Obvious decadal shifts of EASM occurred around the mid- and late 1970 s,the late 1980 s and the early 1990 s,and the late 1990 s and early 2000 s,respectively.Summer rainfall over eastern China exhibited a change in spatial distribution in the decadal timescale,in response to the decadal shifts of EASM.From the mid- and late 1970 s to the late 1980 s and the early 1990 s,there was a meridional tri-polar rainfall distribution anomaly with more rainfall over the Yangtze River valley and less rainfall in North and South China; but in the period from the early 1990 s to the late 1990 s and the early 2000 s the tri-polar distribution changed to a dipolar one,with more rainfall appearing over southern China south to the Yangtze River valley and less rainfall in North China.However,from the early 2000 s to the late 2000 s,the Yangtze River valley received less rainfall.The decadal changes in EASM and summer rainfall over eastern China in the last half century are closely related to natural internal forcing factors such as Eurasian snow cover,Arctic sea ice,sea surface temperatures in tropical Pacific and Indian Ocean,oceaneatmospheric coupled systems of the Pacific Decadal Oscillation(PDO) and AsianePacific Oscillation(APO),and uneven thermal forcing over the Asian continent.Up to now,the roles of anthropogenic factors,such as greenhouse gases,aerosols,and land usage/cover changes,on existing decadal variations of EASM and summer rainfall in this region remain uncertain.

Observed Climate Changes in Southwest China during 1961-2010

The present study focused on statistical analysis of interannual, interdecadal variations of climate variables and extreme climate events during the period of 1961-2010 using observational data from 376 meteorological stations uniformly distributed across Southwest China, which includes Yunnan, Guizhou, Chongqing, Sichuan and Tibet. It was found that temperatures in most of the region were warming and this was especially evident for areas at high elevation. The warming was mostly attributable to the increase in annual mean minimum temperature. The characteristics of high temperature/heat waves are increase in frequency, prolonged duration, and weakened intensity. Annual precipitation showed a weak decreasing trend and drier in the east and more rainfall in the west. The precipitation amount in flood season was declining markedly in the whole region; rainfall from extreme heavy precipitation did not change much, and the portion of annual precipitation contributed by extreme heavy precipitation had an increasing trend; annual non-rainy days and the longest consecutive non-rainy days were both increasing; the extreme drought had a decreasing trend since the 1990s; the autumn-rain days displayed a downward fluctuation with apparent periodicity and intermittency. The number of southwestern vortices was decreasing whereas the number of moving vortices increased.

Asian climate change under 1.5-4 ℃ warming targets

在三种 RCP 情形下面基于 18 个 CMIP5 模型的模拟，这篇文章在全球温暖的上下文在亚洲上在吝啬的温度和降水和他们的极端调查变化 1.5-4 的目标吗？

An analysis of China's CO_2 emission peaking target and pathways

China has set the goal for its CO2emissions to peak around 2030,which is not only a strategic decision coordinating domestic sustainable development and global climate change mitigation but also an overarching target and a key point of action for China's resource conservation,environmental protection,shift in economic development patterns,and CO2emission reduction to avoid climate change.The development stage where China maps out the CO2emission peak target is earlier than that of the developed countries.It is a necessity that the non-fossil energy supplies be able to meet all the increased energy demand for achieving CO2emission peaking.Given that China's potential GDP annual increasing rate will be more than 4%,and China's total energy demand will continue to increase by approximately 1.0%e1.5%annually around2030,new and renewable energies will need to increase by 6%e8%annually to meet the desired CO2emission peak.The share of new and renewable energies in China's total primary energy supply will be approximately 20%by 2030.At that time,the energy consumption elasticity will decrease to around 0.3,and the annual decrease in the rate of CO2intensity will also be higher than 4%to ensure the sustained growth of GDP.To achieve the CO2emission peaking target and substantially promote the low-carbon development transformation,China needs to actively promote an energy production and consumption revolution,the innovation of advanced energy technologies,the reform of the energy regulatory system and pricing mechanism,and especially the construction of a national carbon emission cap and trade system.

Development path of Chinese low-carbon cities based on index evaluation

这个工作作为研究对象从瓷器低碳的试验性项目拿 36 个城市并且使用人均的碳排放和人均的 GDP 把 36 个城市分成四种类型揭示他们的低碳的开发地位；这四种类型是领先的城市，开发城市，迟到者城市，和探索城市。根据一个索引系统，那份量上描述低碳的开发，这研究分析特征，发展趋势，和城市的四种类型的低碳的发展小径。根据国家排出物并且就在为城市的每种类型的发展阶段，挑战，和机会的差别而言的现在的状况和目的，这研究为低碳的路线图介绍建议并且中期、长期(在 2030 )在中国的区域的不同类型的排放趋势线路。

Co-controlling CO2 and NOx emission in China's cement industry:An optimal development pathway study

It is of important practical significance to reduce NOx emission and CO2 emission in China's cement industry.This paper firstly identifies key factors that influence China's future cement demand,and then uses the Gompertz model to project China's future cement demand and production.Furthermore,the multi-pollutant abatement planning model(MAP)was developed based on the TIMES model to analyze the co-benefits of CO2 and NOx control in China's cement industry.During modeling analysis,three scenarios such as basic as usual scenario(BAU),moderately low carbon scenario(MLC),and radically low carbon scenario(RLC),were built according to different policy constraints and emission control goals.Moreover,the benefits of co-controlling NOx and CO2 emission in China's cement industry have been estimated.Finally,this paper proposes a cost-efficient,green,and low carbon development roadmap for the Chinese cement sector,and puts forwards countermeasures as follows:first,different ministries should enhance communication and coordination about how to promote the co-control of NOx and CO2 in cement industry.Second,co-control technology list should be issued timely for cement industry,and the R&D investment on new technologies and demonstration projects should be increased.Third,the phase-out of old cement capacity needs to be continued at policy level.Fourth,it is important to scientifically evaluate the relevant environmental impact and adverse motivation of ammonia production by NOx removal requirement in cement industry.

PM2.5 and tropospheric O_3 in China and an analysis of the impact of pollutant emission control

This study reviewed the status of PM2.5 and tropospheric O3 observations in China(15e55N, 72e136E). Initially, the distribution of tropospheric O3 over the globe and China was determined based on satellite observations made during 2010e2013. The annual mean values were 29.78 DU and 33.97 DU over the globe and China, respectively. The distribution of PM2.5 and seasonal changes in concentrations in China were then simulated using an aerosol chemistry e climate coupled model system, with an annual mean value of 0.51×10-8kg mà3. The contributions from five different aerosols to the simulated PM2.5 concentrations in different seasons were also determined. The relationships among the emissions of aerosols, greenhouse gases and their precursors and radiative forcings were determined with reference to the(IPCC AR5) Intergovernmental Panel on Climate Change the Fifth Assessment Report. From these relationships, the possible effects of controlling O3 precursors and(PM) particulate matter on the climate were considered. The influence of the control of O3 precursors was not totally clear, and reducing emissions of short-lived greenhouse gases and black carbon was considered a secondary measure for short-term(the next 50years) climate-change mitigation. Reducing emissions of CO2 is still the best strategy for meeting the target of a global average rise in surface air temperature of less than 2C. Near- and short-term emission reduction strategies are important for both effective environmental protection and climate-change mitigation.