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Climatic comfort or human thermal comfort has a far- reaching impact on human settlements and human activities. A number of thermal indexes are widely applied in the fields of architectural design, urban planning, human health, and tourism development. As an indispensable and critical part of climatic comfort assessment, scale of thermal sensation not only greatly affects the validity of a thermal index, but also makes the comparison among different thermal indexes possible. At present, a few traditional scales of thermal sensation are generally used for the climatic comfort assessment in different regions without any localized adjustment. Alternatively, experimental investigation and questionnaire survey are adopted to formulate the scale of thermal sensation for a certain area. Therefore, a new approach named "seasonal anchor method" is proposed in this paper, which includes 4 steps --"grading, naming, anchoring, and projecting". Furthermore, based on the long term daily meteorological data (from 1981 to 2010) from 814 national basic meteorological observing stations throughout China, a case study is carried out. In this study, a 7- level scale of thermal sensation, which includes "torrid, hot, warm, neutral, cool, cold, and frozen", is proposed. Meanwhile, the threshold values of each level of thermal sensation for THI (temperature and humidity indexes) and WEI (wind effect index), which can be adopted as a national standard, are generated. Finally, climate-comfortable period and climate-uncomfortable period in China are evaluated, which brings us some meaningful discoveries. [ABSTRACT FROM AUTHOR]

Atmospheric precipitation is the most important link in the process of global water vapor cycle and energy conversion, and it is the material basis for the global ecosystem to maintain stability. Therefore, it is increasingly important to monitor and forecast precipitation for regional climate analysis, water resources evaluation and hydrological process simulation. As an important ecological barrier, the Qilian Mountains plays a critical role in maintaining the natural environment and social development in Northwest China. Thus, it is of great significance to examine the distribution and variation of precipitation in the Qilian Mountains. However, there are relatively few studies on precipitation in mountainous areas due to some factors, such as insufficient measured data, complicated precipitation environment and so on, which limits the further study to some extent. In recent years, with the development of satellite inversion technology, the application of satellite to precipitation retrieval is becoming more and more mature, which provides data support for the study of precipitation in mountainous areas. Therefore, this paper uses the data of TRMM monthly precipitation and ground meteorological station precipitation, combined with the error evaluation and other mathematical statistics and Kriging interpolation method, to calibrate TRMM precipitation, so as to examine the spatiotemporal variations of the zone of the maximum precipitation in the study area. The results show that: (1) The overall performance of TRMM precipitation is good in the Qilian Mountains. The measured annual precipitation of 31 meteorological stations has a high correlation (0.94) with the TRMM data, and the correlation coefficients of the seasonal average precipitation are 0.87 (spring), 0.89 (summer), 0.88 (autumn) and 0.7 (winter). (2) The errors of some stations are large and the low values are overestimated and the high values are underestimated. (3) Annual average precipitation shows a decreasing trend from east to west in the region, and zones of the maximum precipitation in the eastern, central and western parts appear at 4100 m, 4500 m and 4700 m, respectively. The vertical variation rates of the average annual precipitation are 16.6 mm/100 m, 10.8 mm/100 m, 9.8 mm/100 m, respectively. (4) The precipitation fluctuated and increased in the eastern, central and western parts of the study area from 1998 to 2016. The zone of the maximum precipitation also shows a fluctuating upward trend. The maximum precipitation height in each season decreases in the order of summer, spring, autumn and winter. [ABSTRACT FROM AUTHOR]

Over the past hundred years, remarkable changes occurred around global climate. Two significant characteristics of climate changes are temperature mutation and warming hiatus, which led to a variety of extreme climate events of all scales, such as in the north of China. Therefore, revealing the features and rules of temperature mutation and warming hiatus in northern China could provide some basis to deeply understand climate changes, prevent and mitigate disasters as well as improve ecological environment in northern China and in the whole world. Based on the seasonal (monthly) average minimum temperature, average temperature and average maximum temperature data at 357 meteorological stations in northern China and surrounding areas during 1951-2014, this paper analyzes the spatio- temporal variation of three types of seasonal temperature (the average minimum temperature, average temperature and average maximum temperature) mutation and warming hiatus over northern China by using Mann-Kendall test, slide t test and other methods. The results indicate: according to the average minimum temperature, average temperature and average maximum temperature, the abrupt change of temperature and warming hiatus became late and the cycle from abrupt change to warming hiatus became short as the latitude reduces. In spring and winter, the temperature mutation and warming hiatus in the Northeast China were the earliest (1970s- 1980s, 1993- 2002), in North China were the second and in the Northwest China were the latest (1990s-2000s, 1996- 2010). While in summer and autumn, the temperature mutation and warming hiatus in North China were the earliest, in Northeast China were the second and in Northwest China were the latest (1990s- 2010s). There was little distinction among areas in warming hiatus year. Meteorological stations with no mutation and no hiatus were centralized in mountainous regions, high- latitude areas and southern part of North China Plain where the surrounding areas were relatively late in mutation and warming hiatus. The mutations and warming hiatus of same kinds of temperature became late in the order of winter (1981- 1990), spring, autumn and summer (1994-2008) and winter (1995-2008), autumn, summer and spring (1998-2010). The cycle from temperature mutated to warming hiatus became short in the sequence of winter, spring, autumn and summer, during which the average minimum temperature period was the longest in winter (9- 24 a). The average minimum temperature mutated earliest in spring, summer and winter, which occurred during 1972-1999, 1987-1999 and 1971-2000, the average temperature was the second to mutate, while the average maximum temperature was the latest to mutate which occurred during 1975- 2008, 1994- 2008, 1972- 2006. However, in autumn, the mutation of the average temperature was the earliest (1982-2001), the mutation of the lowest average temperature was the second, and the mutation of the highest average temperature was the latest (1987-2001). The warming hiatus of the average minimum temperature, average temperature and average maximum temperature in spring and summer became late successively, which were during 1994- 2008, 1997-2008 and 1997-2010, respectively, while the sequence was opposite in autumn and winter. The lengths of periods from temperature mutation to warming hiatus in each season in order were that of the average minimum temperature (9-18 a), that of the average temperature and that of the average maximum temperature (5- 12 a). In particular, the three kinds of temperatures all mutated earliest in the southern of North China in summer, which is inconsistent with the rule in the whole area that the mutation became late as latitude decreases, and the temperature at most stations in this area did not mutate, which is also inconsistent with the general rule in the whole area. [ABSTRACT FROM AUTHOR]