Free Book from URISA: Foundations of Urban and Regional Information Systems and Geographic Information Systems and Science

Foundations of Urban and Regional Information Systems and Geographic Information Systems and ScienceURISA is pleased to announce the publication of Foundations of Urban and Regional Information Systems and Geographic Information Systems and Science, a 300-page book assembled to celebrate URISA’s 50th anniversary conference. Sponsored by URISA past presidents, the commemorative book discusses some of the research, education, training, and applications foundations that URISA and its members have contributed to urban and regional information systems and geographic information systems and science during the past five decades. The dozens of contributors to this publication, bring their experiences from governments at all levels, private sector firms, research institutes, and universities, represent the ‘Who’s Who’ of influencers in the field.

Dr. Barry Wellar, GISP (President, Wellar Consulting Inc., retired Professor, University of Ottawa, URISA President 1977-1978 and member of URISA’s GIS Hall of Fame) served as publication Editor and coordinated the effort. “The sum of the matter as I see it, is that URISA has an amazingly rich history, and the right people were in the right place at the right time to prepare a book which delves into that record of achievement, and does considerable justice to the many individuals, agencies, ideas, initiatives, etc., that have made URISA the leading international organization in the field of urban and regional information systems and geographic information systems and science. URISA has a long and rich history of producing substantive documents, and I am optimistic that Foundations will be recognized as an important legacy of URISA’s 50th anniversary conference.”

Each of the 23 chapters in Foundations of Urban and Regional Information Systems and Geographic Information Systems and Science contains insights, ideas, suggestions, lessons learned, lessons to be learned, and recommendations regarding information system education, research, training, and application.

The book is currently available, for free, as a downloadable file on URISA’s website, www.urisa.org/foundations, and printed copies, supported with funding from Esri, will be available for purchase at GIS-Pro 2012: URISA’s 50th Annual Conference for GIS Professionals (September 30-October 4, 2012 in Portland, Oregon). Many of the contributing authors will be in attendance and it is anticipated that a book signing event will take place during the conference. Further, the publication will be celebrated in a conference plenary session on Thursday morning, October 4. Visit www.urisa.org/gispro2012 for details about GIS-Pro 2012.

[Source: URISA press release]

A Density Based Accessibility Measure for Mobile Objects

GIScience 2012, Columbus, Ohio, 18-21 September 2012

M.W. Horner and J. A. Downs

“Mobile object analysis continues to be well-studied in GIScience (Hornsby and Egenhofer 2002; Laube et al. 2005; Neutens et al. 2011). Time geography remains the key theoretical framework for understanding mobile objects’ movement possibilities (Miller 2005). Within time geography, recent efforts have sought to enhance its ‘probabilistic’ potential through exploring questions of data uncertainty, spatial representation, and limitations of classical approaches (Kuijpers et al. 2010; Neutens et al. 2011; Winter and Lin 2011). Along these lines, Downs (2010) fused time geography and kernel density estimation in developing timegeographic density estimation (TGDE), which may be used to estimate mobile objects’ probable locations in continuous space, given a time budget between control points (Downs 2010). Downs and Horner (2012) extend TGDE to discrete network space, demonstrating its application with GPS-based vehicle tracking data (Downs and Horner 2012) and using it in searches for travellers’ destinations missing in travel surveys (Horner et al. 2012).

Intensity Values for Traveller 1 (eq. 1).

Intensity Values for Traveller 1 (eq. 1).

“The present paper explores a new direction for TGDE, namely the creation of a densitybased accessibility measure for mobile objects. Related to time geography, accessibility measures have also garnered widespread attention in the literature (Kwan 1998; Miller 1999; O’Sullivan et al. 2000; Yu and Shaw 2008; Delafontaine et al. 2012). Our new metrics gauge how accessible a moving object is to particular opportunities of interest, given the constraints inherent to its movement plan. Thus, we are able not only visualize where the object most likely could have been (Downs and Horner 2012), but we also capture the configuration and magnitude of activities relative to its travel path from both a visual and analytic perspective.”

Data Transformation and Uncertainty in Geostatistical Combination of Radar and Rain Gauges

Journal of Hydrometeorology Journal of Hydrometeorology, Volume 13 Issue 4, August 2012

Rebekka Erdin, Christoph Frei, and Hans R. Künsch

“Geostatistics provides a popular framework for deriving high-resolution quantitative precipitation estimates (QPE) by combining radar and rain gauge data. However, the skewed and heteroscedastic nature of precipitation is in contradiction to assumptions of classical geostatistics. This study examines the potential of trans-Gaussian kriging to overcome this contradiction. Combination experiments are undertaken with kriging with external drift (KED) using several settings of the Box–Cox transformation. Hourly precipitation data in Switzerland for the year 2008 serve as test bed to compare KED with and without transformation. The impact of transformation is examined with regard to compliance with model assumptions, accuracy of the point estimate, and reliability of the probabilistic estimate. Data transformation improves the compliance with model assumptions, but some level of contradiction remains in situations with many dry gauges. Very similar point estimates are found for KED with untransformed and appropriately transformed data. However, care is needed to avoid excessive transformation (close to log) because this can introduce a positive bias. Strong benefits from transformation are found for the probabilistic estimate, which is rendered positively skewed, sensitive to precipitation amount, and quantitatively more reliable. Without transformation, 44% of all precipitation observations larger than 5 mm h−1 are considered as extremely unlikely by the probabilistic estimate in the test application. Transformation reduces this rate to 4%. Although transformation cannot fully remedy the complications for geostatistics in radar–gauge combination, it seems a useful procedure if realistic and reliable estimation uncertainties are desired, such as for the stochastic simulation of QPE ensembles.”

Aerial Survey and Spatial Analysis of Sources of Light Pollution in Berlin, Germany

Remote Sensing of EnvironmentRemote Sensing of Environment, Volume 126, November 2012, Pages 39–50

Helga U. Kuechly, Christopher C.M. Kyba, Thomas Ruhtz, Carsten Lindemann, Christian Wolter, Jürgen Fischer, and Franz Hölker

“Highlights

  • A 391 square kilometer urban light pollution map is produced with 1 m resolution.
  • Geospatial analysis of the map compares lighting to land use type.
  • Lighting associated with streets accounts for 1/3 of the total zenith uplight.
  • Land use types of differing areas are compared equivalently using mean brightness.
  • The utility of night aerial photography for light pollution studies is demonstrated.

“Aerial observations of light pollution can fill an important gap between ground based surveys and nighttime satellite data. Terrestrially bound surveys are labor intensive and are generally limited to a small spatial extent, and while existing satellite data cover the whole world, they are limited to coarse resolution. This paper describes the production of a high resolution (1 m) mosaic image of the city of Berlin, Germany at night. The dataset is spatially analyzed to identify the major sources of light pollution in the city based on urban land use data. An area-independent ‘brightness factor’ is introduced that allows direct comparison of the light emission from differently sized land use classes, and the percentage area with values above average brightness is calculated for each class. Using this methodology, lighting associated with streets has been found to be the dominant source of zenith directed light pollution (31.6%), although other land use classes have much higher average brightness. These results are compared with other urban light pollution quantification studies. The minimum resolution required for an analysis of this type is found to be near 10 m. Future applications of high resolution datasets such as this one could include: studies of the efficacy of light pollution mitigation measures, improved light pollution simulations, economic and energy use, the relationship between artificial light and ecological parameters (e.g. circadian rhythm, fitness, mate selection, species distributions, migration barriers and seasonal behavior), or the management of nightscapes. To encourage further scientific inquiry, the mosaic data is freely available at Pangaea: http://dx.doi.org/10.1594/PANGAEA.785492.”

Mapping Spatial and Temporal Patterns of Mediterranean Wildfires from MODIS

Remote Sensing of EnvironmentRemote Sensing of Environment, Volume 126, November 2012, Pages 12–26

Noam Levin and Aliza Heimowitz

“Highlights

  • We developed a new algorithm to map burnt areas from the MOD13Q1 product of MODIS.
  • Fire scars larger than 100 ha were accurately mapped, with accuracies > 80%.
  • Most fires in Israel take place in the early and late dry seasons.
  • Wildfire hotspots were related to herbaceous vegetation and military training zones.”

“Wildfires are part of the Mediterranean ecosystem, however, in Israel all wildfires are human caused, either intentionally or un-intentionally. In this study we aimed to develop and test a new method for mapping fire scars from MODIS imagery, to examine the temporal and spatial patterns of wildfires in Israel in the 2000s and to examine the factors controlling Israel’s wildfire regime. To map the fires we used two ‘off-the-shelf’ MODIS fire products as our basis—the 1 km MODIS Collection 5 fire hotspots, the 500 m MCD45A1 burnt areas—and we created a new set of fire scar maps from the 250 m MOD13Q1 product. We carried out a cross comparison of the three MODIS based wildfire scar maps and evaluated them independently against the wild fire scars mapped from 30 m Landsat TM imagery. To examine the factors controlling wildfires we used GIS layers of rainfall, land use, and a Landsat-based national vegetation map. Wildfires occurred in areas where annual rainfall was above 250 mm, mostly in areas with herbaceous vegetation. Wildfire frequency was especially high in the Golan Heights and in the foothills of the Judean mountains, and a high correspondence was found between military training zones and the spatial distribution of fire scars. The use of MODIS satellite images enabled us to map wildfires at a national scale due to the high temporal resolution of the sensor. Our MOD13Q1 based mapping of fire scars adequately mapped large (> 1 km2) fires with accuracies above 80%. Such large fires account for a large proportion of all fires, and pose the greatest threats. This database can aid managers in determining wildfire risks in space and in time.”

An Improved Distance Metric for the Interpolation of Link-based Traffic Data using Kriging: A Case Study of a Large-scale Urban Road Network

International Journal of Geographical Information ScienceInternational Journal of Geographical Information Science, Volume 26, Issue 4, 2012

Haixiang Zou, Yang Yue, Qingquan Li & Anthony G.O. Yeh

“The interpolation of link-based traffic data is an important topic for transportation researchers and engineers. In recent years the kriging method has been used in traffic data interpolation from the viewpoint of spatial analysis. This method has shown promising results, especially for a large-scale road network. However, existing studies using the Euclidean distance metric, which is widely used in traditional kriging, fail to accurately describe the spatial distance in a road network. In this article we introduce road network distance to describe spatial distance between road links, and we propose an improved distance metric called approximate road network distance (ARND), based on the isometric embedding theory, for solving the problem of the invalid spatial covariance function in kriging caused by the non-Euclidean distance metric. An improved Isomap algorithm is also proposed for obtaining the ARND metric. This study is tested on a large-scale urban road network with sparse road-link travel speeds derived from approximately 1200 ‘floating cars’ (GPS-enabled taxis). Comparison was conducted on both the Euclidean distance metric and the ARND metric. The validation results show that the use of the ARND metric can obtain better interpolation accuracy in different time periods and urban regions with different road network structures. Therefore, we conclude that the improved distance metric has the ability for improving kriging interpolation accuracy for link-based traffic data within real situations, providing more reliable basic traffic data for various traffic applications.”

Temporal and Spatial Analysis of Phosphate Concentrations in Surface Waters in the ‘Gelderse Vallei’, the Netherlands

Master thesis, Universiteit Utrecht, 30 March 2012

Simon van Dijk

“High phosphate concentrations in surface waters are regarded as bad for the ecosystem integrity and leads to loss of aesthetic, ecological and economic value of the system. Therefore the European Union set targets for phosphate concentrations in the Water Framework Directive, which must be met by 2015 and ultimately by 2027. For the majority of the surface waters in the ‘Gelderse Vallei’ these targets are not met at the moment.

Spatial distribution of the mean Total-P values in mg/L over the period 2005-2010.

Spatial distribution of the mean Total-P values in mg/L over the period 2005-2010.

“This study focuses on the temporal and spatial trends of phosphate concentrations in the ‘Gelderse Vallei’, with respect to the Water Framework Directive. An extensive dataset with phosphate concentrations is provided by water board ‘Vallei & Eem’ and is analyzed by using ordinary linear regressions and ANOVAs for the temporal trends. For the spatial analyses maps are made to provide quick visual output of spatial patterns.

“For the temporal analyses no clear statistical trends are shown, however 70% of all ordinary linear regressions were negative, possibly indicating decreasing phosphate concentrations in the ‘Gelderse Vallei’. From the spatial analyses phosphate concentrations tend to decrease in northern direction. The change in phosphate between time periods does not show a clear spatial pattern.

“Considering the standards from the Water Framework Directive, respectively 60% and 50% of the studied surface waters will not meet the standards by 2015 and 2027. For water board ‘Vallei & Eem’ this means that measures should be taken to meet these standards. Furthermore, more attention should be given to the south of the ‘Gelderse Vallei’, for phosphate concentrations in the north are meeting the standards by 2015 and 2027 while in the south most surface waters do not meet the standards by 2015 and 2027.

“Extending the dataset, extending the amount of analyzed surface waters and extending research on explanations of the trends can contribute to a better understanding of the trends and therefore to stronger conclusions and indicating possible measures.”

Call for Nominations: The Marble-­Boyle Undergraduate Achievement Award in Geographic Science

The application deadline is October 15, 2012

The Association of American Geographer’s Marble Fund for Geographic Science is pleased to announce the new Marble-Boyle Undergraduate Achievement Awards. These awards aim to recognize excellence in academic performance by undergraduate students from the United States and Canada who are putting forth a strong effort to bridge geographic science and computer science as well as to encourage other students to embark upon similar programs. These awards, together with the William L. Garrison Award for Best Dissertation in Computational Geography, are activities of the Marble Fund and are supported by donations to the Fund.  In the case of the current awards, the support of Mr. Jack Dangermond is gratefully acknowledged.

Duane Marble and Ray Boyle in Honolulu at the Joint U.S.–Australia GIS Meeting in 1982

Duane Marble and Ray Boyle in Honolulu at the Joint U.S.–Australia GIS Meeting in 1982

The award is named for Dr. Duane Marble, creator of the Marble Fund, and for the late Dr. A. R. (Ray) Boyle who was a major contributor to the early development of both computer cartography and geographic information systems.  Ray Boyle was born in England in 1920 and served with the British Admiralty during World War II.  After the war, he developed and patented many graphic systems for plotting and digitizing and was the inventor of the “free cursor” digitizing system that was the basis for the digital entry of much early spatial data. After moving to Canada in 1965 he was appointed Professor of Electrical Engineering at the University of Saskatchewan where, among many other achievements, he developed the first digital system for nautical chart production for the Canadian Hydrographic Service. He worked for many years with Dr. Roger Tomlinson on the technical evaluation of GIS software and was also an active member of the IGU Commission on Geographical Data Sensing & Processing for many years.

Applications

At any time during the stated application period applicants may submit an application using our online application form. This form will ask applicants to provide:

  • Personal information (name, address, email, phone number, etc.) together with a statement of their intention to apply for the award.
  • An essay of no more than 800 words, formatted in 12 pt Times New Roman, double-spaced with 1” margins, identifying the individual’s areas of interest within geographic science and computer science, a description of his or her career goals, and a statement as to  how his or her  joint background in geographic science and computer science will help to meet these goals.
  • A letter of recommendation from the student’s faculty advisor, department chair or program director. The letter should clearly address both the applicant’s academic performance as well as their potential for a career or further education that utilizes their geographic science and computer science background. Recommendation letters must be signed and written on institutional letterhead. They must be sent in PDF form directly by the referee to the Chair of the Review Committee to grantsawards@aag.org .
  • An official or unofficial copy of the applicant’s transcript(s) with all relevant courses in geographic science and computer science, and grades received in these courses, highlighted.
  • For each highlighted course, the applicant must  provide a one or two sentence description of the course content, the text book(s) used (if applicable), and the name(s) of the instructor(s).

All elements of the application must be received at grantsawards@aag.org no later than the close of  business in Washington, D.C. on October 15, 2012.

Full information on the awards and the application process may be found at http://www.aag.org/cs/marble-boyle

[Source: AAG press release]

World Ocean Council Panel to Explore How to Expand Fishing Industry Efforts to Gather Ocean, Weather, and Climate Data

World Ocean CouncilSenior fishing industry representatives and scientists will focus on the role of the fishing industry in collecting ocean, weather and climate data, and how to scale up these efforts, at a World Ocean Council (WOC) panel during the Seafood Summit (Hong Kong, 5-9 September).

The fishing industry can play a significant role in collecting data that: a) contributes to describing the status, trends and variability of ocean, weather and atmosphere conditions and b) improves the understanding, modeling and forecasting of ocean ecosystems and resources.

Lori Kennedy, co-owner/cofounder of Louisbourg Seafoods, said, “Fishers like to be included in data collection programs and have the potential to gather information in areas not frequented by other ocean users. Increased data can be used to improve safety at sea and the responsible use and management of ocean resources.”

“The panel will consider the ocean industry data gathering experience to date, constraints and opportunities for expanding the use of fishing vessels, and how the fishing industry can learn from and collaborate with other ocean industries in collecting ocean and atmospheric information”, noted Paul Holthus, WOC Executive Director.

The fishing industry panel is part of the WOC “Smart Ocean/Smart Industries” initiative to facilitate, scale up and coordinate data collection by ocean users, e.g. fisheries, shipping, oil/gas, offshore renewables. The initiative is working to develop efficient, cost effective data gathering by ocean industries that builds on existing efforts, creates economies of scale and is integrated into national and international ocean observing and science programs.

Improved and expanded information from industry vessels and platforms will contribute to improved modeling of weather, ocean conditions and climate change and will support safer more responsible use of ocean space and resources – with clear benefits for business, society, science, and governments.

[Source: World Ocean Council (WOC) news release]

Spatial Analysis of Longleaf Pine Stand Dynamics after 60 Years of Management

Proceedings of the 16th Biennial Southern Silvicultural Research Conference, 2012

John C. Gilbert, John S. Kush, and Rebecca J. Barlow

“There are still many questions and misconceptions about the stand dynamics of naturally-regenerated longleaf pine (Pinus palustris Mill.). Since 1948, the “Farm Forty,” a forty-acre tract located on the USDA Forest Service Escambia Experimental Forest near Brewton, Alabama, has been managed to create high quality wood products, to successfully promote natural regeneration, and to minimize management costs. Management consists of periodic inventories, prescribed fire, and harvests, which have created an uneven-aged stand structure with a range of age classes. A GIS database was created by stem-mapping all pines greater than or equal to 3.1 inches dbh (diameter at breast height). This database contains information for over 5,000 trees and provides a unique opportunity to explore longleaf pine stand dynamics spatially. The variations in densities and size classes across the tract will be evaluated to provide information about how longleaf pine grows and the dynamics of long-term management.”