Mark Henderson

Spatiotemporal change in China's frost days and frost‐free season, 1955–2000

[1] From 1955 to 2000, China has experienced a decrease in the number of frost days, while the length of the frost-free season between the last spring freeze and the first fall frost has increased. Three distinct regimes can be detected in the time series: up to about 1973, the annual number of frost days was about 2 d higher than the 1961-1990 average; from 1973 to 1985, the annual number of frost days held close to that average with remarkably little interannual variability; and after 1985, the annual number of frost days decreased rapidly with distinct reversal around 1992. The dates of first and last frost show two patterns: before 1980, these dates fluctuated around the 1961-1990 average, but after 1980 (and especially from 1993) the frost-free season was rapidly lengthened. The numbers of frost days are highly correlated with minimum temperature (Tmin) in north China in spring and fall; while in south China frost dates correlate with minimum temperatures in winter. Generally, the seasonal relationships between Tmin and frost days are significant in both the temporal and spatial domains when seasonal average Tmin falls within a range of +/- 10 degrees C. Analyzing annual and seasonal influences on the number of frost days, we find that water vapor plays a significant role. Regionally, the greater influence on the length of the frost-free season in south China has been the delayed onset of the autumn frost, while in north China the spring and autumn dates each have a comparable influence on the length of the frost-free season. The initial lengthening of the frost-free season lagged about 10 years behind the rapid increase in daily minimum temperatures, while the decrease in the annual number of frost days lagged by about 15 years.

Sectors and Skills: Career Trajectories and Training Needs of MPP Students

Abstract Public policy programs have come to attract students with increasingly diverse backgrounds and career aims, but curricular changes have been modest. Using a data set on MPP alumni from Harvard’s Kennedy School, we analyze career trajectories through different sectors and specializations, examining relationships among trajectories, perceptions of public service, and particular skill needs. Although government remains an important destination, we find a predominance of idiosyncratic paths and a diversification of employment trajectories over time. Perceptions of employment as public service and reports of skill use vary significantly by sector. Although certain general skills (communication, systematic thinking about problems, and workload management) are widely used, there are notable differences in other skill areas (policy design and political analysis are more used by government and nonprofit workers; economics is more used in the private sector). Programs may want to consider these differences in skill use in prioritizing what is taught, and how.

Training Policy Students to Hit the Ground Running: The Design of an Integrative Core Course.

Effective public policy education must prepare students both to integrate the lessons of multiple disciplines and to apply these across diverse substantive areas. How can these objectives best be accomplished? Research on adult learning and professional education points toward applied, problem-based, cooperative, and student-driven pedagogy. This article describes the design and implementation of an integrative core course in which Master of Public Policy (MPP) students work through the stages of policy analysis in a series of current policy problems. The instructor serves as a coach, and a professional “client” for each problem provides feedback grounded in experience. Engaged learning is enhanced through teamwork, peer instruction, and opportunities for reflection and self-assessment. Over time, refinements in problem and client selection and the integration of skills have been informed by practical concerns and formal program assessment.

A Core-Periphery GIS Model of the Historical Growth and Spread of Islam in China

Abstract This study presents the methodology and results of a core-periphery GIS model of the historical growth and spread of Islam in China based on a dataset of 1,774 mosques. These sites were organized into data subsets according to their founding dates during five major dynastic periods in Chinese history: Tang/Song, Yuan, Ming, Qing, and Republican. Core areas were identified and mapped based on where mosques clustered during each period. North China was the paramount core region in all periods. Not until the late Qing and Republican periods did the Northwest and Yunnan compare with North China, while coastal China never developed into a core area.