NOAA Extended Reconstructed Sea Surface Temperature V3b dataset (ERSST) and Hadley Centre Sea Ice and Sea Surface Temperature dataset (HadISST) were used in this paper for analyzing the observed ENSO intensity changes during 1900-2015. It is demonstrated that ENSO amplitude changed clearly over the past more than 100 years. From the beginning of the 20th century to the 1950s, ENSO intensity weakened while it strengthened significantly from the 1950s to the late 1990s, especially after the 1970s. After 2000, the intensity declined slightly. The weakest ENSO intensity occurred from the 1920s to the 1950s, during which the northsouth width of ENSO spatial pattern narrowed and the maximum sea surface temperature anomaly (SSTA) center had a westward shift. In contrast, the width was the widest and the maximum SSTA center had an eastward shift after the late 1970s when ENSO intensity kept a strong magnitude. And then the width and the center had an opposite changing tendency after 2000.

Based on the observation of daily temperature data and 30 models data provided by Coupled Model Intercomparison Project (CMIP5), five extreme temperature indices including mean maximum temperature (TXAV), mean minimum temperature (TNAV), heat wave duration index (HWDI), frost days (FD) and warm nights (TNF90) have been calculated to evaluate simulation capability of each model in terms of spatial field in climate state and the trend of extreme temperature in China. Results show that most models can better reflect the spatial pattern of extreme temperature indices in climate state. The spatial pattern of TNAV, TAXV and FD can be better simulated, as the correlation coefficient of most models are more than 0.9, and there are good consistency between models. TNF90 and HWDI are poorly captured by models, as the correlation coefficient are lower than 0.7 and there are large differences between models. Models also simulate the same trend change of average extreme temperature index at national scale as the observation, but their most simulation strength of trend are weak. Compared with spatial pattern in climate state, the models simulation of trend spatial pattern for extreme temperature are not good. Thereinto, TNAV is relatively well simulated, the correlation coefficient of a third of models are larger than 0.6. The correlation coefficient for other indices are lower than 0.6. The models simulation ability ranks of space and time are in good consistency. Based on the comprehensive space-time simulation ability, the top 5 models are MPI-ESM-P, CMCC-CM, IPSL-CM5A-LR, CESM1-CAM5 and ACCESS1-3. The best multi-models ensemble (BMME) can reduce the biases and narrow the biases areas.

The winter of 1670/1671 was abnormal severe cold over eastern China. In this study the coldness situation of the winter was reproduced by means of historical literature records using our historical climate data system. A map of coldness records distribution including heavy snow, frost, trees and bamboo freeze injuries, and the maps of the depth of snow cover and of the snow days were plotted. It is shown that the south boundary of river freeze-up reached south to 27°N, which is the most southern location of river freeze-up in historical records of China, and days with snow lying in South China were never seen in the modern times. Based upon the coldness records of places and the critical temperatures necessary for river freeze-up and tree winterkill, the extreme minimum temperatures were deduced quantitatively. It indicateded that the deduced minimum temperature in Hengshan county of Hunan province in January 1671 was -15 ℃ , which is 7 ℃ lower than the absolute minimum temperature record in the modern times (1951-2000). Following the severe winter, there was a large range of severe drought, which is different from the usual climate (a large range of rain in summer), and a hot summer in northern China and middle-lower reach of the Yangtze River. So that a rare great amplitude of temperature occured in that year. 1670/1671 winter was in the Maunder minimum solar activity period. There were few large volcano activities in the world ahead of the severe winter. As for the sea temperature, there was a very strong El Niño event in 1671, and 1670 was a non-El Niño year before the El Ni?o events. This severe winter corresponded to the warmest phase of sea temperature in the equatorial east Pacific Ocean. So, the winter of 1670/1671 is a typical severe winter in the Little Ice Age of China. It is a rare case of severe cold winter with abnormal hot summer, and also a special case of a wide range of severe drought following a severe cold winter.

The long-term tendency of tropical cyclone (TC) position were examined when they reach the different intensities including life-time extreme, tropical storm and typhoon in this study. The data were obtained from JTWC, CMA and JMA from May to November of 1980-2013. The results indicated that TCs over the western North Pacific presented the poleward tendency at most of intensity levels, and the tendency was statistically significant in all three datasets and reached up to 90, 93 and 113 km per decade, respectively. Besides, the positions, when TCs achieved the level of typhoon and tropical storm, had relatively apparent poleward and westward tendency. By analyzing the variation characteristics of factors including vertical wind shear, sea surface temperature, and genesis potential index, further study was conducted to give a possible physical explanation for the long-term tendency.

Using multi-source of monthly temperature and precipitation data on the basis of preliminary integration and quality control, monthly mean temperature, maximum temperature, minimum temperature, and precipitation time series covering 1913-2014 at observation Baoding are interpolated by both two approaches of standardized method and multivariate linear regression. The interpolation results analyzed by cross validation are that the standardized method is more right for temperature data, but for precipitation is the method of multivariate linear regression. Then, the better interpolated time series are homogenized by the penalized maximal F test (PMF), and results indicate that those monthly hundred-term temperature and precipitation data are relatively continuous, only two breakpoints have been detected in the mean minimum temperature series, respectively, by the same type of instrument replacement and station relocation, and also have been adjusted by Quantile-Matching (QM), in the interest of construction of the monthly hundred-term temperature and precipitation time series at observation Baoding. Moreover, we compare the data here with the homogenized monthly temperature and precipitation data during 1913-2014 at observations Beijing and Tianjin from some aspects of trend change and correlation analysis, which show that the data we constructed in this paper are relatively logical and errorless, thus can fill the blank of lack of a complete homogeneous hundred-term climate series for quantitative analysis of climate change in North China Plain.

The uncertainty of the probabilistic distribution of precipitation extremes over Xinjiang during 1961-2014 was discussed by using multi-function method. Results suggest that precipitation extremes easily occur in Xinjiang against the background of the climate change from warm-dry to warm-wet, which could take impact on the fitting of precipitation extremes. The uncertainty exists in the selection of functions and extreme estimations. In order to reduce the uncertainty, it’s suggested to apply the composite analysis with results of GEV, Gen. Logistic, Log-Pearson 3, Pearson 6 and Wakeby functions, when the study is conducted over the whole Xinjiang. For the single station analysis, the compositive curve graph with boundary of the extreme values is suggested to be provided.

From the micro perspectives of individual farmers, we aim to study perception and adaptation of farmers who act as the subject of agricultural activities to climate change. The hilly and gully areas of northern Shaanxi are selected as the study area, using empirical analysis of questionnaires survey combined with semistructured interview method, in order to examine farmers’ perception and adaptation to climate change and investigate factors that influence farmers’ adaptive activities through binary logistic regression model. The results show that farmers’ perception of climate change tendency is relatively consistent, that summer temperature and winter temperature have increased in recent 5 years, and precipitation has decreased. But there are some deviations from the observation data. The proportion of farmers who have taken adaptive measures is not very high, only 57.8% of respondents have adjusted their farming practices to mitigate the impacts of climate change. Farmers’ adaptive behaviors are affected by their perception of climate change. Social-economical characteristics of household have significant impact on farmers’ adaptive activities. However, there is little relationship between farmers’ adaptive behaviors with household demographic characteristics, such as gender, age and education level.

It is a key issue to calculate how much emission quota has been used for UNFCCC parties, taking into account their historical greenhouse gas emssions. From the perspective of inter-person equity, this paper defines ratio for greenhouse gas emission per capita per year, presents the results of calculation for 142 parties based on data at UN Demographic Yearbook, national inventory report, biennial report, biennial updated report and national communication, and estimation by International Energy Agency and Carbon Budget Project and other researchers and international orgizations. It is found that ratio for greenhouse gas emission per capita per year for the U.S. is higher than 3.33, that for China is 0.50-0.70, that for India is less than 0.30. According to ratio for greenhouse gas emission per capita per year, the 142 parties are categorized into 9 groups. It is found that ratio for greenhouse gas emission per capita per year can be applied to measure the emission allowance a party has been used, while it can also help to improve the transparency of emission information.

With vigorous implementation of China’s urban symbiosis development, positive effects in various aspects have been increasingly emerging. Firstly, the status quo of China’s urban symbiosis development and utilization was introduced and a statistical analysis of the emission reduction of CO₂ and CH₄ caused by recovery of iron and steel scraps, waste paper and waste plastics was made in China from 2011 to 2014 using the greenhouse gases (GHG) emission inventory calculation method provided by IPCC. The cumulative recovery of renewable resources during China’s main urban symbiosis development in 2011-2014 was 803.275 Mt, and the recovery of iron and steel scraps, waste paper and waste plastics was the largest, which respectively accounts for 62.2%, 18.0% and 8.2% of the total recovery in 2014. The cumulative emission reduction of GHG caused by recovery of iron and steel scraps, waste paper and waste plastics in 2011-2014 was 27.962 Mt CO₂-eq, 954.695 Mt CO₂-eq and 22.502 Mt CO₂-eq, respectively, totaling 1005.159 Mt CO₂-eq, so the GHG emission reduction effect is remarkable.

A General Circulation Model, BCC_AGCM2.0 from National Climate Center of China, was used in this work. And the effective radiative forcing (ERF), newly defined by IPCC AR5, was adopted in discussing the radiative forcing and climate response for methane. The ERF due to the change in methane concentration from pre-industrial was 0.49 W/m². Because of the change in methane concentration, the global annual mean surface temperature increased by 0.31℃ , and precipitation increased by 0.02 mm per day. And there were remarkable increases (by approximately 4%) in the cloud cover in high latitudes of both Northern and Southern Hemisphere, and the cloud cover decreased (by approximately -3%) sharply in tropical areas.

Paris Climate Change Conference was successfully concluded with the Paris Agreement, which is a milestone for the world in combating climate change collectively. Analysis of the author shows that by participating in IPCC assessments and conducting national climate change assessments, China has been increasing its understanding of the issue. It was the first time that China’s top leader attended the conference for the Parties, which indicated the acknowledgement of the rationality and necessity of climate change response by China at different levels. That also reflected the commitment of China to including climate change in its ecology improvement program and pursuing a low-carbon society and economy. To ensure the success of the Paris conference, China made big efforts. Such an example of China’s constructive participation in the global governance shows that China is a responsible power. These principles, such as to create a future of win-win cooperation, with each country making contribution to the best of its ability, a future of the rule of law, fairness and justice, and a future of inclusiveness, mutual learning and common development, will serve as China’s guidelines for its efforts to facilitate the implementation of the Paris Agreement and participate in the design of international systems.