Table of Content

    25 September 2013, Volume 32 Issue 9 Previous Issue    Next Issue
    Special Column: Space-time Behavior and Geography
    Beyond binaries: Reflections on hybrid geographies
    KWAN Mei-Po
    2013, 32 (9):  1307-1315.  doi: 10.11820/dlkxjz.2013.09.001
    Abstract ( )   PDF (506KB) ( )   Save
    In the last century, geography as a discipline has witnessed a rift between spatial-analytical geographies and social-cultural geographies, resulting in lasting effect on the discipline. In this article, I explore how the social-theory/spatial-analysis split in geography arose. I argue that, instead of insisting on a unitary identity for the discipline, forging productive relations between different traditions, specialties and subfields seems to be a more viable strategy for enhancing the status of geography. I consider some possibilities for reconnecting social- cultural and spatial-analytical geographies by revisiting the relations between epistemology and method in geography. I suggest that there can be both positivist and non-positivist use of quantitative/GIS-based spatial analysis and qualitative methods, which makes the mixed-use of the two methods possible. Then I examine the notion of hybridity and its potential for redressing this polarizing tendency in the discipline, and summarize the existing practice of hybrid geographies. There are at least three common practices towards hybrid geographies. The most common hybrid practices are those that use quantitative or GIS methods to address issues informed by critical geographies. Another type seeks to cross the boundary between geo-spatial technologies and a qualitative understanding of the lived experiences of individuals in various cultural contexts. And the third type attempts to integrate critical social theory and spatial analytical methods. As a conclusion, I offer some thoughts on the possibility of a "post-social-theory, post-spatial-analysis" future for geography. This means a future in which social- cultural geographies and spatial-analytical geographies are no longer represented as the conflicting poles. And I point out that the major challenge for geography as a discipline is how to cherish the diversity and richness of perspectives while enhancing its status in the academic community and society.
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    The application of the qualitative GIS in space-time research
    KWAN Mei-Po, GU Zhilian, TA Na, CHAI Yanwei
    2013, 32 (9):  1316-1331.  doi: 10.11820/dlkxjz.2013.09.002
    Abstract ( )   PDF (26636KB) ( )   Save
    GIS has been largely understood as a tool for the storage and analysis of quantitative data since the early days of their development; their use in qualitative or mixed-method research has been limited to date. This positivist perspective has caused much of the critical discourse on GIS since the early 1990s. In recent years there have been a growing number of attempts to redress this particular understanding of GIS and explore the possibility of using GIS in qualitative research, that is, qualitative GIS, which has included the strategy of integrating grounded theory and visualization, the integration of GIS and ethnography, and so on. Qualitative GIS has been a crucil tool for the mixed-method research in geography today. Time geography has been a significant perspective for the analysis of human activity and movement in space-time. It analyzes human behavior through an integration of the temporal and spatial dimensions, and has been a helpful perspective in a wide range of space-time research. Nevertheless, it has been criticized for ignoring subjectivity, omitting social and culture context, and leaning towards quantitative analysis. In resent years, the development of qualitative GIS and its application in mixed-method research has provided a foundation for the integration of qualitative analysis in time geography. This paper reviews this development, with a focus on an approach to GIS-based narrative analysis developed by Kwan et al(2008) called "Geo-narrative". Geo-narrative is based on extending current GIS capabilities for the analysis and interpretation of narrative materials such as oral histories, life histories, and biographies. Which has three central elements: narrative analysis as the qualitative approach; 3D GIS-based time-geographic methods as the representational framework; and 3D-VQGIS as the GIS-based computer-aided qualitative data analysis component. This paper discusses how the application of Geo-narrative in time-geographic research can provide an effective environment for qualitative data collection and analysis in ralation to behavior, time and space, interpretation and re-interpretation during integration of the qualitative analysis in time-geographic analysis. Through this, a recursive and interactive qualitative analysis has been integrated with behavioral analysis in time geography within GIS. In addtion, to illustrate the analytical process using Geo-narrative and show how it can be used to perform qualitative analysis in time geography, we present a case example that draws on Kwan's study on the impact of anti-Muslin hate crimes on the lives of the Muslim women in Columbus, Ohio, after the attacks on theWorld Trade Center and the Pentagon on September 11, 2001.
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    The trend and hot issues in the field of space-time research: Based on the literature citation relationships and knowledge map
    GU Jie, ZHOU Suhong,YAN Xiaopei, CHAI Yanwei, ZHENG Zhong
    2013, 32 (9):  1332-1343.  doi: 10.11820/dlkxjz.2013.09.003
    Abstract ( )   PDF (7740KB) ( )   Save
    The field of space-time research has received wide attention in the past few decades. In order to explore the trend and hot issues objectively, a database is set up by the software Histcite, consisting of 2263 related papers included in the database of "Web of Science" from 1999 to 2013 and 78139 indirect papers referenced by the papers in first group. The historical citation relationships and the hot-spot papers, key words, and journals are visualized on the platform of Citespace. At the same time, the citation relationships between the 2263 related papers are also analyzed by Histcite. Some conclusions are drawn as follows: Firstly, the widely cited papers are exploding, with the trend from discussions on the theoretical framework to methods and applications. In detail, after the first widely cited paper, titled as "what about people in regional science" written by H?gerstrand in 1970, appears in the citation tree-rings, there scattered certain other widely cited papers during the 1970s when the theory of time geography was being formed. There appear a few hot-spot papers during the 1980s, including the papers from the field of transportation geography. After the 1990s, with the application of GIS, more and more publications related to the subject of space-time were cited, and the trend became more remarkable after 2000s. The content of studies gradually shifted from description of space-time behavior to the interpretation of it. As T-GIS technology matures, space-time behavior will be used not only as an object to be decrypted, but also as a variable to explain space-time phenomena and social problems, and the value of the application will be gradually revealed. Secondly, the main trends of the papers related to space-time published during 1999-2013 have been discovered, including the integration of space-time framework and GIS, the integration of space-time and travel demand, the impact of internet and mobile technology on spatio-temporal behavior, and the gender differences et.al. The potential widely cited but non-mainstream papers are in the field of transportation modeling and sociology. Finally, the key words of hot topics and journals related to space-time are also recognized.
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    Temporally integrated human mobility and health research
    KWAN Mei-Po, GUO Wenbo, CHAI Yanwei
    2013, 32 (9):  1344-1351.  doi: 10.11820/dlkxjz.2013.09.004
    Abstract ( )   PDF (916KB) ( )   Save
    With the development of GIScience, geography's focus on important social issues intersects with other cognate disciplines, which in return enhances the vitality of geography itself. It is important to consider the temporal dimension and human mobility in geographic research, since time is closely linked to space, the very basic dimension of geographic studies. Health is one of the most important issues in people's daily life, which is closely bound up with space-time behavior. The perspective of activity-mobility system will contribute to the breakthrough of health-related research. Drawing upon recent research on human mobility, this paper reviews research and methods of accessibility, travel experience and well-being, and health and disease. GIS broke the constraints of geometry methods of accessibility research, and scholars developed various methods and aspects of accessibility research, of which the nearest research has taken accessibility to health and healthcare into account. Furthermore, the temporal dimension enriches the connotation of accessibility, considering time as well as space, and pays more attention to the old, the disabled, the low-income, children and women. Well-being and travel experience are one of the hottest topics of human mobility research. Traditional questionnaire survey can help capture travel experience and well-being from both objective and subjective side. Geo-narrative offered a method to get better understanding and visual presentation of travel experience from more detailed, empathizing and reasonable view. Health has been a deep-seated issue, and few researchers have probed into the relationship between health and human mobility. Health-related contextual variables are introduced into health-related mobility research, which presents the environmental elements such as air pollution, water pollution, etc. Coupled with high time-space accurate GPS methods, sampling method for health data collection makes it possible to give in-depth analysis of health-related mobility. The paper, in particular, explores individual accessibility to healthcare in low-income neighborhood in central Ohio from a spatial-temporal view using GIS, and it is found that the employed are facing poorer accessibility to healthcare than the unemployed. Another example is the factors influencing smokeless tobacco use in rural Ohio Appalachia through interview with 23 adolescent smokeless tobacco users and 38 adult smokeless tobacco male users, and it is found that culture, social network and easy accessibility to tobacco enhances the use of smokeless tobacco. The two cases show multiple methods of GIS, quantitative and qualitative, applied on health-related researches. Finally, prospects of temporally integrated research on human mobility and healthcare are discussed. The combination of theory and methods of different disciplines is essential to make the breakthrough in geographies of health and healthcare.
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    Methods in urban temporal and spatial behavior research in the Big Data Era
    QIN Xiao, ZHEN Feng, XIONG Lifang, ZHU Shoujia
    2013, 32 (9):  1352-1361.  doi: 10.11820/dlkxjz.2013.09.005
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    The rapid development of information technology has taken us into the "Big Data Era", changed the organization and structure of urban space and residents' behavior, and also caused transformation of the methods in urban temporal and spatial behavior research. On the basis of summarizing the problems of traditional methods such as poor data accuracy, small sample size, weak continuity, and higher costs, this paper first combs through the data acquisition and processing technology for web data mining, residents' behavior data collection and analysis, and network map integration and visual development, which can affect the transformation of the research methods. Then it reviews the latest progress in applying big data to urban temporal and spatial behavior research at home and abroad from the perspectives of residents' behavior, urban space, and urban hierarchy, and builds up a method framework for urban temporal and spatial behavior research based on big data application. The methods in urban temporal and spatial behavior research are going through a great transformation because of the emergence of massive and various information data. Data collection methods have changed from yearbook statistics, social questionnaire survey, in-depth interview to mining of network data (social network data) and application of new spatial position technology (GPS, smart mobile phone, LBS, etc.), and the data shows obviously new characteristics such as large sample size, real-time dynamic, micro and detail, with more attention paid to the extraction of residents' geographic position information. However, as to specific research methods, the traditional ones are still widely used, such as descriptive statistical analysis, cluster analysis, factor analysis, gravity model, network analysis, space-time prism, etc. Generally speaking, the researches of urban temporal and spatial behavior have obvious characteristics of using "new" data and "old" methods to study "newer" and "older" problems at the present stage, and their research scope has also expanded from residential scale to urban space and regional range. However, problems still exist with the current research, such as how to eliminate fictitious data, how to learn and innovate analytical methods, how to expand research field and embody characteristics of the era. Therefore, it is necessary to promote the cross and integration of related disciplines such as sociology, economic geography, cultural geography, tourism geography, computer science, mathematics and geographic information science, in order to find new analysis methods, and also reinforce the research of residents' behavior and urban space by using social network (Twitter, Flikr, Facebook, Sina Microblog, etc.) data or other web (SouFun.com, Dianping.com, Zhaopin.com, Taobao.com, etc.) data, and guide innovation of urban planning methods.
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    Progress in space-time behavior research in China
    CHAI Yanwei, TA Na
    2013, 32 (9):  1362-1373.  doi: 10.11820/dlkxjz.2013.09.006
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    As a unique perspective for understanding the complex relationships between human activities and urban environments in space and time, the space-time behavior approach has become an influential methodology in China's urban geography since 1990s. Aiming at promoting communications and exchanges among urban geographers in different contexts, this article provides a critical review of space-time behavior research in China. Ever since time geography and activity-based model were introduced to China's urban geography, space-time behavior research in China has benefited from the fruitful theoretical and methodological progress made in Western geographical research. On one hand, GPS and mobile phone tracking technologies have been integrated into activity-diary surveys to collect more accurate and real-time activity-travel information. On the other hand, advanced statistical models and geocomputational and 3D geovisualization methods have been adopted in more recent empirical literature in China. Yet, while Chinese urban geographers have made more methodological progress in data collection and analytic tools thanks to the development of GPS and GIS technology, theoretical development still lags behind. However, space-time behavior research in China, with planning-oriented characteristics, offers a unique framework for understanding urban transformation in China. It has become a new perspective for understanding the complexity and diversity of human behavior patterns in the transitional cities in China. In other words, space-time behavior research tries to describe and interpret urban spatial structures and spatial reconstructing in urban China from the perspective of individuals' behaviors. The impacts of danwei-based urban spatial organization and its disappearance, as well as the impacts of suburbanization on individuals' daily activities, have been studied carefully. Especially, this approach emphazes how spatial restructuring impact individuals' daily life experiences, which in turn are related to the issues such as life quality, social equity and environmental sustainability. Urban geographers in China have begun to apply the space-time activity approach to the socio-spatial issues in the cities by focusing on daily-activity experiences of low SES (socioeconomic status) populations. And the development of the low-carbon city movement in China has prompted the application of the space-time behavior approach in understanding the impacts of land use characteristics on travel-related carbon- dioxide emissions through individuals' travel decisions. At the same time, planning practices based on the space-time behavior approach is carried out in urban transportation, tourism, and urban planning. The space-time behavior approach has become a very useful human-oriented approach to land use and transportation planning in China. The article concludes by discussing key theoretical and practical challenges for future development of space-time activity research in China.
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    Urban and Regional Development
    Internal functional division and spatial clustering in the Yangtze River Delta: Based on workforce data
    SONG Weixuan, CHEN Wen, CHEN Peiyang
    2013, 32 (9):  1374-1382.  doi: 10.11820/dlkxjz.2013.09.007
    Abstract ( )   PDF (6305KB) ( )   Save
    Urban function has always been one of the hot-spot subjects having attracted the attention of domestic and overseas geographical circles. China has mainly followed the steps of western countries in researching the issue of urban function, but has seldom made original explorations. In addition, China's researches on urban function are unnecessarily confined to the classification of the functions and lack overall measurement of regional urban function systems and their complementation. In recent years, along with the emergence of integrated regions, the research on the urban functions of the regions with high integration degree such as the Yangtze River Delta has become a hot topic. With the Yangtze River Delta as research object, 139 districts and counties in the region as basic spatial units, based on the 10% sampling survey data among the national census data in 2000 and 2010, this paper has extracted the information on industrial workforce population divided by "industrial type" of each district and county, consolidated and reduced them into seven functional types, and analyzed the internal functional division and spatial clustering characteristics of the Yangtze River Delta from two lateral layers, namely, structure attribute and space attribute. This paper first measured the scale differentiation and spatial clustering degree of each function in the region by means of Lorenz curve and Ellison-Glaeser index(EG), and then analyzed the spatial clustering of functions in each district and county with functional location entropy as basic data, and surveyed the spatial distribution and change of each function clustering district. The research shows that, as seen at national level, in the Yangtze River Delta, "commerce and trade" and "industry" are generally the main functions, showing the trend of being further strengthened, while agricultural function is being weakened continuously. The internal functional division structure in the Yangtze River Delta shows the trend of constant professionalization, and professionalized service functions like "commerce and trade", "modern logistics", and "education and scientific research", etc., are gradually centralized in the core areas of three central cities, Shanghai, Nanjing and Hangzhou, while the districts clustered with "industry" function are distributed in Shanghai-Nanjing axle areas, and are gradually transferred and spread to the areas along the Yangtze River and the coastal areas of Hangzhou Bay. Along with the deepening of regional integration development, the functions born by individual units in the Yangtze River Delta are being gradually transformed in professionalized direction, and also, the same functions have gradually clustered in similar spatial location, forming a spatial clustering district featured by some professional function. The professional service functions such as regional business, commerce and trade, logistics, education, and scientific research, etc., will be increasingly centralized in central cities, and it's easy to form a manufacturing clustering district in the areas close to central cities. Generally speaking, the areas having stronger relationship with central city Shanghai in the Yangtze River Delta have higher degree of functional professionalization. With the scales of workforces in different industries, as shown in the previous two census of population, as preliminary data, this paper can approximately reflect the pattern of functional division in internal regions of the Yangtze River Delta, but meanwhile, it has certain deficiencies. For example, it neglects the differences among labor-intensive and technique- and capital-intensive industries in terms of employment rate and labor productivity, etc. These deficiencies need to be corrected in the future research by subdividing industrial categories, introducing economic data, and so on.
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    Regionalization of ecosystem services of Beijing-Tianjin-Hebei Area based on SOFM neural network
    MA Cheng, LI Shuangcheng, LIU Jinlong, GAO Yang, WANG Yang
    2013, 32 (9):  1383-1393.  doi: 10.11820/dlkxjz.2013.09.008
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    Abstract:Studies showed that ecosystem services are closely related to land utilization. Human activities have been relentlessly developing and using the land, causing serious exhaustion of land resources and making ecological environment change from bad to worse, which in turn poses severe threat to the sustainable utilization of ecosystem services. For sustainable land use and human well-being promotion, it is important to integrate ecosystem service into the land use decision-making process. Creating partitions based on different ecosystem services is of great significance for land use and management of ecosystem services. Taking Beijing-Tianjin-Hebei as a case area, the study in this report assessed the ecosystem service value of each unit based on IGBP land use data from 2001 to 2009. Regionalization of ecosystem service was created by SOFM Neural Network. In order to recognize the main ecosystem services of each region, the study calculated the hot spots of ecosystem service by ArcGIS. Combined with national major function oriented zoning, the study put forward proposals for making the policies on the future land development. The results indicated that Beijing-Tianjin-Hebei Area can be divided into four regions based on ecosystem service values: Ⅰ. Bashang Plateau and northwest Hebei mountain region, Ⅱ. Yanshan and Taihang Mountains region, Ⅲ. Central and southern Hebei Plain region, and Ⅳ. Bohai Sea coastal area. The ecosystem service value of Bohai Sea coastal area continued to rise while that of the other areas decreased to different degrees: Ⅱ>Ⅰ>Ⅲ. Wind and spring floods eroded soils in region Ⅰ and the soil are quite fragile. In order to conserve water and soil, proper land-use policies should be made for region Ⅰ. The key restoration measures include improvement of rangeland management, financial incentives to elimination of overstocking, and re-vegetation with appropriate rest periods during which grazing should be banned. Most of the hot spots of biodiversity service are distributed in region Ⅱ, but the value goes down with each passing year. Therefore, policy makers should pay more attention to biodiversity conversation in this region. As part of rapid urbanization efforts, the type of ecosystem service in region Ⅲ is quite simple. Food production is the dominant service while other services are quite low especially for water conservation and soil formation. On the premise of guaranteeing food production, proper policies should be made to adjust the proportion of urban land use to increase other ecosystem service such as carbon sink and pollination services. The resources of beach soils of region Ⅳ are rich, but the utilization ratio is low because of serious soil salinization. It is urgent for decision makers to provide guidance for salinization control, such as promoting water saving agricultural techniques and reducing artificial recharge of groundwater, to limit the increase of salinity. In addition, region Ⅳ should make full use of wetland because wetland can provide many services such as water conservation. The results indicated that SOFM Neural Network has strong advantage in objectivity and clear classification and is of great importance as a supplement to ecosystem service regionalization. The dividing method of GIS and SOFM clustering can identify regional differences and similarities of ecosystem services value and works well on ecosystem services regionalization.
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    Estimation and comparison of ecological footprints of urban households' consumption with diffrent income: A case study in Kaifeng City, Henan Province
    ZHANG Pengyan, WANG Kaiyong, ZHANG Wei, HAN Bin, CHEN Long
    2013, 32 (9):  1394-1400.  doi: 10.11820/dlkxjz.2013.09.009
    Abstract ( )   PDF (693KB) ( )   Save
    Taking three residential areas of different income levels in Kaifeng City, Henan Province in 2009 as a case, this study analyzes the ecological footprint of Kaifeng City using the theory and methods of ecological footprint and questionnaire survey. Based on the survey in the three residential areas, Banqiao, Kangping and Longchengxiangxieli Garden, the ecological footprint of consumption of biological resources and energy are calculated. The results indicate that, firstly, in the three residential areas, from the viewpoint of per capita ecological footprint, energy consumption in the overall ecological footprint is at a higher level; secondly, from the viewpoint of biological consumption, per capita ecological footprint of pork is the largest, followed by dairy products, and the reason is that meat and dairy food production requires more land area; thirdly, from the viewpoint of different types of per capita ecological footprints, in Banqiao residential area the percentage of fossil fuel land and building land is the largest, followed by arable land and grassland. Based on the analysis above, we conclude that the higher the residential area's living standard is, the greater the ecological footprint is, and vice versa. This study demonstrates that Kaifeng city's polarization phenomenon is the main reason for the unfairness between the two residential areas in terms of ecological footprints and carbon emissions. Finally, we provide some advices to the urban households and policymakers, such as promoting economic development, actively creating more jobs, and leading the residents to rational consumptions.
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    Research progress on island economy
    QIN Weishan, ZHANG Yifeng
    2013, 32 (9):  1401-1412.  doi: 10.11820/dlkxjz.2013.09.010
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    Island is a special regional unit with unique development models and paths. Islands, with their unique locations, resources and environmental advantages, play an important role in the modernization process. Besides being the frontier of the defense of national sovereignty and security, the islands are the important basis to strengthen the marine economy and expand the development space of China. As an important transitional region connecting the continents and oceans, islands often have important traffic advantage of port and waterway. Islands are also an important platform to protect marine environment and maintain marine ecosystems. In recent years, with more emphasis being put on marine territories world wide, researches on islands also increased among the scholars at home and abroad. In this paper, we started with analyzing the meaning of island economy. On the basis of others' accomplishments, we tried to define what island economy is. Based on extensive literature study, we conducted a systematic analysis on island economy from the four aspects as follows: its development, evolution and transformation, its development model, the coordination and optimization of man-land relationship in the development process, and its impact on resource and environment. Foreign scholars focused on sustainable economic development of an island as well as the development of various industries in island economy, and they had a series of research achievements especially on island tourism development. Domestic scholars focused on island fisheries, tourism and other industries, and carried out active research on overall economic development of an island, its economic evolution, economic development model, spatial differentiation, and so on. However, as shown in the literature published so far, in this research field there is still lac of systematic studies, research teams and achievements, especially on the formation, evolution mechanism, the elements of island economy and the mechanism of their interactions. The studies on the resources and environmental effects of island economy were mainly combined with the sustainable development of island economy, and most of the studies on this topic mainly focused on the impact of island economy (especially the tourism) on resources and environment and how to protect them in order to maintain the sustainable development of regional economy. Finally, we suggested furture direction of the research on island economy: (1) Launch systematic studies on island economy by using the Man-land Relationship Areal Theory as a guide, combined with system science theories, regional economic development theories and industrial structure evolution theories. (2) Conduct quantitative analysis based on the studies on the bearing capacity of resources and environment; (3) Pay attention to the support of 3S technology and use participatory investigation method in order to obtain more intuitive and reliable data. (4) Conduct comprehensive studies on the development and sustainability of island economy to serve practice.
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    Applications of wavelet analysis to hydrology: Status and prospects
    SANG Yanfang, WANG Zhonggen, LIU Changming
    2013, 9 (9):  1413-1422.  doi: 10.11820/dlkxjz.2013.09.011
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    In this paper, wavelet analysis methods, mainly including wavelet basis function, continuous and discrete wavelet transform and wavelet threshold de-noising, were introduced first. Then, current researches and applications of the wavelet analysis methods to various aspects of hydrology were summarized and reviewed from three points of view: research significance, current researches and applications, and key and difficult problems and the inadequate applications to hydrology. The six aspects of wavelet-based hydrologic analysis include: continuous wavelet-based analysis of hydrologic time series' characteristics under multi-temporal scales, discrete wavelet decomposition and reconstruction different sub-signals of hydrologic time series, quantification of complicated variability of hydrologic processes, wavelet de-noising in hydrologic time series, wavelet cross-correlation analysis of hydrologic time series, and wavelet-based hydrologic time series simulation and forecasting. Finally, several suggestions and opinions on the future researches and applications of wavelet analysis methods in hydrology were discussed. They focus on selection of wavelet basis function, wavelet threshold de-noising, wavelet decomposition, wavelet cross-correlation analysis, and wavelet aided forecasting.
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    Spatial downscaling of TRMM precipitation data based on DEM in the upstream of Shiyang River Basin during 2001-2010
    MA Jinhui, QU Chuang, ZHANG Haixiao, XIA Yanqiu
    2013, 9 (9):  1423-1432.  doi: 10.11820/dlkxjz.2013.09.012
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    Rainfall data are often obtained by ground-based observatories. However, traditional measurements based on raingauge stations can't reflect the spatial variation of precipitation effectively, especially in the Shiyang River Basin, which is a typical area with complicated terrain and climatic characteristics. There is great potential in making hydrological predictions by using satellite-based rainfall estimation. As a precipitation radar satellite, TRMM has been collecting plenty of fine temporal-spatial precipitation data. However, when applied to local basins and regions, the spatial resolution of TRMM products is too coarse, so it is necessary to develop a method to improve the spatial resolution of TRMM before using it. In this paper, a statistical downscaling algorithm based on the relationship between Tropical Rainfall Measuring Mission (TRMM) 3B43 dataset and the DEM(GTOPO30)from USGS is presented. A multiple linear regression model was established under the scale of 1 km. By applying a downscaling methodology based on 1 km resolution, the TRMM3B43 0.25°×0.25° precipitations were downscaled to 1 km×1 km pixel precipitation for each year from 2001 to 2010. The downscaled precipitation estimates were subsequently validated by using the observations obtained from 34 raingauge stations for the duration of 10 years in the Shiyang River Basin. These results showed that: the downscaling procedure resulted in significant improvement in spatial resolution and data quality for annual precipitation during 2001-2010, as well as for a typical dry year (2001) and wet year (2007), and captured the trends of precipitation in spatial distribution and inter-annual variability of annual precipitation with the coefficient of determination R2 ranging from 0.45 to 0.93 at 34 different raingauge stations.
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