Book Review: Stat Spotting: A Field Guide to Identifying Dubious Data

November 21, 2022 Leave a comment

I recently read the book Stat Spotting: A Field Guide to Identifying Dubious Data (University of California Press, 2013). As the focus of the book is to encourage the reader to think critically about the information they receive, with a particular focus on statistical data, and as this focus is shared by this blog, I believe that the book will be useful particularly to the readers of Spatial Reserves. The book’s author, Dr Joel Best, sociology and criminal justice professor from the University of Delaware, adheres to the book’s “field guide” focus; that is, providing short, useful examples. The book’s focus is that data should be examined critically. That theme should sound quite familiar to the readers of this blog as indeed we have examined this theme from multiple angles for over a decade. The book’s examples alternate between topics that are grim and topics that are fun, but all are incredibly relevant despite the book being nearly a decade old. All of the topics make for excellent case studies that one could use with one’s colleagues or a professor could use with students for class discussions. These include topics such as, “How important are family dinners?” (in increasing student achievement and reducing risky behavior), “Is autism an epidemic?”, and “Do we have runaway health spending?”

One of my favorite tenets running throughout the book is the author’s words that “all statistics are the products of people’s choices. If they’d made different choices, the figures would be different, but with enough information, we should be able to evaluate those choices.” Another thing I love about the book is the author’s counsel that, “we need to be very careful when we can’t tell who produced the figures, why or how, and when we can’t be sure whether consistent choices were made in the measurements at different times and places.” Indeed!

One of the most useful sections of the book to the readers of this blog I believe is the section entitled “common signs of dubious data.” Dr Best advises to search for the background of the data, when the numbers seem inconsistent with benchmark figures, or when severe examples are used for supposedly common problems. He also says to look for blunders, where the numbers just seem too high or too low. Again germane to this blog is the author’s advice to “Look for the sources of the data.” Dr Best also says to examine the definitions: Broad definitions lead to big numbers. Furthermore, what if the definitions change over the course of the issue being studied? That matters, too. Examine how the measure was created in the first place. Surveys may use loaded questions that encourage particular responses. Look at the packaging of the results: Generalizations may be based on a biased or misleading sample. Be on the lookout for rhetoric, sometimes evident in phrases such as “long term trends.” Finally, examine debates: Rival explanations should be looked at. Identify different causes of the problem.

The Stat Spotting book. As is evident in this photo, I checked it out from a library but you could also buy the book. Either way, it is an insightful and relevant encouragement to think critically about data.

I highly recommend instructors and GIS practitioners, or anyone working with data – to read and use this book.

–Joseph Kerski

Categories: Public Domain Data

The Water Point Data Exchange

November 7, 2022 Leave a comment

Data about water is critical to urban and rural planning, sustainability, human health, and much more. Water data is often disparately gathered, managed, and served. The mission of the water point data exchange: https://data.waterpointdata.org/ (WPdx) is to solve these challenges by unlocking “the potential of water point data to improve rural water services through evidence-based decision-making.” At the time of this writing, the repository had over 406,566 records from 54 countries. More than just a data repository, the WPdx seeks to gather a community of contributors and collaborators. The WPdx has three main components:

WPdx Data Standard

The WPdx Data Standard was collaboratively designed for data collection from rural areas at the water point or small water scheme level. The core parameters included in the WPdx Data Standard are parameters which are commonly measured by governments, non-governmental organizations, and researchers to enable easy sharing without changing the types of data typically collected. The WPdx Data Standard is managed and updated on an as-needed basis by a Global Working Group. The site provides a link to the entire WPdx Data Standard.

Global Data Repositories

The WPdx Data Repository is a cloud-based data library that enables sharing of global data that is compliant with the WPdx Data Standard. Data is fully open and free to access. Data is machine readable via an API. The repository includes an online data playground for analysis and visualization. I tested the visualization tools with success; to access the WPdx Global Data Repository, click here. An enhanced subset of the data, WPdx+ is also available. Please click here to learn more about two datasets.

Decision Support Tools

WPdx currently offers 4 decision support tools to improve evidence-based decision making. The tools were designed in response to the most frequently asked questions in a survey of government water experts. To learn more about the tools, click here. The tools include:

  1. Measure Water Access By District. How many people lack basic access per district? In which districts should investments be focused?
  2. Prioritize Locations for Rehabilitation. Which rehabilitation would reach the most people? Where are people currently unserved due to a broken water point?
  3. Prioritize Locations for New Construction. Which new locations would reach the most people? Where are people currently unserved by an existing water point?
  4. Predict Current Water Point Status. Which water points are at highest risk of failure? Why? Where should preventative maintenance be focused?
The Water Point Data Exchange.

As the theme of this data blog is being critical of information, readers of this blog will be interested in the following statements posted on the site:

Functionality datasets represent a snap-shot at one point in time. They do not indicate whether sources identified as non-functional will be fixed the next day, the next week or never – sources identified as non-functional are not necessarily permanently out of service.  Further, it is difficult to arrive at a useful comparison of different data sets without considering the context at play in each country/district where data sets originate. See “What factors can influence the long-term functionality of water points?” for more on this. Data is provided “as-is” from data contributors, noted in the “source” attribute. Any attributes reformatted by the WPdx team are noted in the “converted” field. No additional validation or verification is done by WPdx. Lastly, data on WPdx has been uploaded by multiple sources and may not be statistically representative of national water point functionality.

The data site is straightforward–tables are fairly easily filter-able and download-able. There is a mapping tool on the site, but I suspect most users will want to filter and download the data tables and bring the data into their own GIS.

I encourage you to give this resource a try.

Joseph Kerski

Categories: Public Domain Data

GIS Ethics site of case studies recrafted

October 24, 2022 Leave a comment

The GIS Ethics site at Penn State University has recently been recrafted: https://sites.psu.edu/gisethics

With support from the National Science Foundation, The GIS Professional Ethics Project has produced this curated collection of geospatial ethics case studies available as Open Educational Resources at GISEthics.org (formerly GISProfessionalEthics.org). The Project also helped establish graduate ethics seminars on the ethical implications of geospatial technologies at Penn State, Oregon State University, and the University of Minnesota. This site has expanded to include 18 case studies, including a timely new case entitled “Flood Mapping” by urban planner Clarke Shupe-Diggs. There is also a new list of related case study collections, which we first wrote about earlier this year, here.

The site is well laid out and the contents are incredibly useful. As an educator, I found the section “How to Analyze Case Studies” particularly helpful.

David DiBiase, curator of the site and one of the principal investigators, is welcoming further suggestions to the site and recently posted, “Along with everyone who has contributed to this effort over the years, I hope the collection is useful to you.”

Part of the newly revamped GIS Ethics site.

–Joseph Kerski

Categories: Public Domain Data

Updates to Named Landforms of the World data

October 10, 2022 Leave a comment

My colleague, Esri Chief Cartographer Charlie Frye, has completed work on the updates to the Named Landforms of the World, version 2. This is now available in the ArcGIS Living Atlas of the World. The following essay serves as the best place to get started:

Introducing Named Landforms of the World, version 2 (esri.com)

Included in the data set are four global sub-layers representing landforms, provinces, divisions, and their respective cartographic boundaries. There are three ways to get started with this data:

  1. Explore the layers in the viewer instant app.
  2. Add the layers to your own web map.
  3. Download a map package for ArcGIS Pro for further analysis.

One of the contributors to this effort created this informative story map with information about landforms and adding tectonic processes to landform data.

This data set is based on core science, is authoritative, well documented, and fills a much needed gap in global spatial data. In my opinion it is excellent for use in research and in education. Landforms are a cross-disciplinary theme that can be used in land use, population, climate and weather, hydrologic, and other studies.

Part of the newly improved landforms of the world data as viewed in ArcGIS Online.

I highly encourage you to examine and use this newly improved data set!

–Joseph Kerski

Categories: Public Domain Data

Book Review: Ctrl-Z: The Right to Be Forgotten

September 26, 2022 Leave a comment

I recently read the book Ctrl-Z: The Right to be Forgotten, and recommend it for the readers of this blog for several reasons. Its author, Dr Meg Leta Jones, professor of Communications, Cultures, and Technology from the University of Georgetown, an expert in the subject of data and society, takes the reader on a journey through the complex issues of data privacy in a compelling way. The book is not focused on location privacy, per se, but the wider context. Many locational issues are touched on in the book, and more importantly, by reading it, you will more fully understand the broader context into which location fits.

The book begins by stating that personal data affects, relationships, employment, academic success, and so much more, and the intersection of personal data with technology means that we must understand and deal with its implications. Indeed! The subtitle of the book “right” refers to if, when, and how companies have a duty to delete or hide information at the request of users. The author argues that the right to be forgotten can be innovative, liverating, and globally viable.

In short, reading essays in this blog about privacy that we have written about for years, such as here, along with reading Dr Jones’ book will give the reader a robust understanding of the issues and why they matter. I would also recommend this book for any professor teaching ethics as reading and discussion assignments, in full or with selected sections of the book.

Chapters 1 and 2 in the book unpack the options for those seeking recourse when personal information haunts them. There are no shortage of court cases and other examples detailed in these chapters and elsewhere in the book; the author has extensive knowledge and has selected the most relevant of these. Chapter 3 focuses on theoretical and conceptual challenges aroudn the right to be forgotten, while Chapter 4 criticizes the way in which technology issues have been framed. Chapter 5 focuses on how to constuct digital redemption within legal systems and how information stewardship can be addressed. Chapter 6 makes the strong point that interoperability is necessary for the development and viability of the right to be forgotten.

One of the most valuable things about the book is the equal treatment that Dr Leta Jones gives to technological, legal, and the social side of this issue. Another thing I found valuable is discussion about the Organization for Economic Cooperation and Development’s guidelines ont the protection of privacy and the transborder flows of personal data. For example, the “collection limitation principle” means that there should be limits to the collection of personal data and any such data should be obtained by lawful and fair means and where appropriate, with the knowledge or consent of the data subject.

I also found very valuable the way the author discusses information stewardship, asking “what should be preserved, and why?” The author states that the web is a communicatons and information resource, but it is a poorly preserved one. We cannot treat it as an ongoing permanent record. There is no systematic approach to the web, which is part of its appeal, but we can still ask “what should be preserved, and why?” I think about this quite a bit, when dealing with the following spatial data issues, and more we could discuss in the comments section after this essay: Where are those map layers I used last year? Have they changed or moved? How I can keep my story maps that are based on old tools viable in the future without a staff to help me? Without a CD reader at my fingertips, how can I efficiently digitize the vast amount of spatial data I still have locked in physical media? (see my video here). I am increasingly asked by data users about “traffic data from 2018” or “UAV imagery from 2020”, or just last week, “TIGER street segments from 1990”. Are we capturing such things? Much of GIS data needs are understandably current, or as near to real time as possible. However, increasingly, people are wanting snapshots over time. And, what about the complex issues of changing formats in the context of changing software tools, operating systems, and ways of serving data?

Ctrl-Z: The Right to be Forgotten–Book.

I recommend this book for anyone working with location-based–or any other type–of data. Search the Spatial Reserves data blog for the term “book” or “book review” to read other reviews of books that are relevant to geospatial data.

–Joseph Kerski

Categories: Public Domain Data

Bringing ‘bare-earth’ mapping to life with FABDEM

September 12, 2022 Leave a comment

FABDEM (Forest And Buildings removed Copernicus DEM) lets you build powerful maps and 3D simulations of the earth’s surface and accurately model natural hazards. For more information, visit: https://www.fathom.global/product/fabdem/ 

Forests and Buildings removed Copernicus DEM (FABDEM) is a newly available global Digital Terrain Model (DTM) created in collaboration between researchers at Fathom and the University of Bristol FloodLab. FABDEM is available at one arc second (~30m) grid spacing and is the world’s first global DTM to have both trees and buildings removed. The new DTM provides GIS users with a high-resolution representation of the Earth’s topography, from which important ‘bare earth’ measurements can be extracted.

FABDEM was derived from the Copernicus GLO-30 DEM using machine learning and offers a new high-resolution solution to medium and large-scale remote sensing efforts. This provides a significant improvement on the previous industry standard global DTM, increasing the potential for spatial analysis, modelling and surveyance. FABDEM represents a notable advance for global bare-earth DEMs, introducing many opportunities for the GIS community.

A brief history of Global Terrain Data

Fairly recent developments have seen a shift away from older satellite data to newer, finer resolution data. Old global DEMs generated at three arc second (~90m) grid spacing include SRTM, MERIT, TanDEM-X 90 and Copernicus GLO-90. FABDEM was developed using Copernicus GLO-30, a dataset at one arc second resolution, and regarded as the ‘gold standard’ of global DEMs. Published earlier this year, FABDEM demonstrates a large improvement in terrain model accuracy and overcomes some of the shortcomings found in alternatives DTMs; they are not true global datasets, are Digital Surface Models (DSM) and therefore not suitable for the same uses, contain ‘no data’ regions due to cloud or snow cover or have larger vertical errors.

Figure 1: Comparison of Copernicus and FABDEM. With buildings and forests removed, FABDEM depicts a much smoother elevation dataset absent of ‘noise’ from surface objects.

Prior to FABDEM, the only other DEM that removed surface objects was MERIT DEM, a forest and error removed DEM built on dated and error prone satellite data. At the time of release, MERIT was the closest thing to a global DTM. By removing buildings, FABDEM goes one step further, leapfrogging MERIT as the most comprehensive error-removed DTM. The finer spatial resolution of FABDEM in comparison with MERIT provides more detail, improving spatial analysis capabilities and boosting the confidence and accuracy of conclusions made. The improvement in resolution from ~90m to ~30m between the two datasets means that one cell in MERIT DEM is now represented by nine cells in FABDEM. This vastly increases the detail level and enhancing a user’s ability to detect smaller features across the terrain that were not previously distinguishable. One particular benefit of this would be flood modelling, with stream identification, relic channels and floodplains becoming more detectable.

Machine learning in DEM building

Machine learning methods were adopted to remove forest and building height bias from Copernicus DEM when creating FABDEM. The correction algorithm is trained on reference data from twelve nations, accounting for various climates and types of infrastructure, increasing the applicability of FABDEM across a wide range of climate zones and urban extents.

FABDEM makes use of the growing availability in global building and forest coverage data. This data is used to train the algorithm to remove this bias using random forest regression models. Different machine learning models were used for forests and buildings, each containing different key predictors. Incorporation of these datasets ensures the machine learning methods applied produce a close ‘bare earth’ estimate for disciplines that require detailed topographic information.

Comparisons with MERIT and Copernicus DEM have revealed that FABDEM has consistently lower errors in urban, forest and boreal forest regions, highlighting the improvement in data quality. Visual comparisons also highlight significant reductions in noise in comparison to MERIT.

Applications of FABDEM

There are many disciplines that make use of global terrain data that will benefit from the improved resolution and accuracy of FABDEM. Research and geoscience are particular examples. Visualisation of Earth’s topography is necessary for glaciology, as well as flood and landslide assessments. Topography is vital to modelling within these disciplines, with the quality of predictions increasing alongside DTM resolution. Global shoreline change analysis and sea-level rise modelling also make use of DTMs. The increased resolution of FABDEM will help to bring more accurate measurements to many uncertain fields such as these that are critical to assessing the impact of climate change.

Transport planning and mapping are further potential uses of FABDEM, providing elevational information at prospective locations, ensuring optimal solutions relating to economic, social and environmental challenges. The same applies to wider planning, where DTMs are used in conjunction with DEMs and DSMs. This use extends further, providing vital topographic information such as ‘line of sight’ for evacuation routes during natural disasters, supply logistics and even military operations. Gaming, flight simulation and virtual reality are also potential uses of FABDEM, providing a topographic landscape for virtual environments within modern technological developments.

Conclusion

FABDEM offers novel global terrain data to GIS users to improve measurements within many vital disciplines. The improvement in resolution and decrease in error in contrast with industry predecessors offers closer ‘real life’ terrain estimates – used for tackling important societal issues relating to climate change research, disaster relief, defence and more. Such accuracy could only be achieved using advanced machine learning methods that help to remove unwanted artefacts. This error correction has produced a widely applicable dataset with small vertical errors, capitalising on what other global DTMs lack. The resolution of the dataset means LiDAR is more accurate at smaller scales, but where local datasets are scarce or unavailable, and as a global dataset, FABDEM is both comprehensive and accessible.

About the author

Sam Himsworth, Graduate GIS Specialist, Fathom

Sam works within Fathom’s technical team as a Graduate GIS Specialist, having graduated from the University of Exeter with a BSc in Geography with Applied GIS. During this time he gained an enthusiasm for GIS (Geographic Information Systems). Drawn to the academic environment of Fathom, Sam brings his experience in learning about open-source GIS, remote sensing, and the ability to interpret complex spatial and numerical datasets developed at university to his role at Fathom.

About FABDEM

FABDEM (Forest And Buildings removed Copernicus DEM) lets you build powerful maps and 3D simulations of the earth’s surface and accurately model natural hazards. Derived from Copernicus GLO 30 and built using machine learning methods, FABDEM is the first global digital elevation model to remove forests and buildings at a 30-metre resolution to give a true picture of ground-level terrain. Developed in tandem with the University of Bristol, FABDEM’s high-resolution digital terrain data ensure it is valuable across the insurance and engineering sectors, and for GIS mapping and geospatial analysis.

For more information, visit: https://www.fathom.global/product/fabdem/ 

Categories: Public Domain Data

Numbers Don’t Lie: Book Review

August 29, 2022 Leave a comment


At once thought-provoking, witty, and actually fun to read, Vaclav Smil’s book Numbers Don’t Lie: 71 Things You Need to Know About the World tackles common questions such as “Is flying dangerous?” and “What makes people happy?” to those that are fun to ponder, such as “Which is more energy efficient—planes, trains, or automobiles?” and “How much do the world’s cows weigh?” And as the book’s themes are central to that of this blog, I trust that this book review will be valuable to our readers. I also recently pushed an even more complete review of this book in a recent issue of the Journal of Geography.

The book meets what I believe its objective to be: To explain things that happen in the world through statistics. In contrast with the author’s previous books on energy policy and other specialized topics, here the author seeks to educate a more general audience. Indeed, Bill Gates wrote in August 2021 that Smil is his “favorite author” and that Numbers Don’t Lie is Smil’s “most accessible book yet.” Given the title, as
expected, numbers abound, but Smil explains aspects of our modern society and how that society came to be in engaging ways.

In line with our “be critical of the data” mantra of this blog, the readers will no doubt want to know about the author: The author is a Distinguished Professor in the Faculty of Environment at the University of Manitoba in Winnipeg, Canada. His research includes energy, environmental, food, population, economic, historical and public policy studies, and he was the first non-American to receive the American Association for the Advancement of Science Award for Public Understanding of Science and Technology. He has written dozens of books from energy to eating meat, and from China to ecology.


This book touches on themes into which Smil has delved in his previous books. Thus, the author brings a scientific perspective to Numbers Don’t Lie that recent books on “how to understand the world” or even “how to understand the world through maps” written by journalists and others may not. As the general educated public is the intended audience, this often funny book is one you could give to a friend or
relative to enjoy. Admittedly, I would have liked to see more maps, but I found the photos and charts to be interesting and well-chosen. I recommend that this book be considered as a source for readings in high school and undergraduate geography and GIS courses. It is easy to imagine that a Smil question such as “What’s worse for the environment—your car or your phone?” can spark a fruitful discussion in classes and also with workplace colleagues.

The book also touches on a key geographic theme that the world is a complex, dynamic place. Not everything can be explained, such as longevity rates for the Japanese or why Panama has a higher happiness index than Italy. That the author acknowledges these mysteries is honest and refreshing.


Furthermore, not everything in the book is a fact or a number, which is also a good thing. Some sections present hypotheses or opinions. You may not agree with everything postulated by the author, for example, that the 1880s might have been the most consequential decade in human history for its technological enhancements. But even if you don’t, debates about the “most influential decade technologically” or “politically” or “socially” can again be more fruitful than if everyone in your classroom or workplace is in agreement.


I believe the book is also useful for a deeper reason: Many geographers and GIS professionals are well-grounded in the tenets of the book How to Lie with Maps by Mark Monmonier that is currently in its third edition (2018). They’ve either read the book, or if not, understand the power that maps and geovisualizations have on shaping opinion and attitudes. A central theme of Spatial Reserves, my own long-running blog (https://spatialreserves.wordpress.com), is to be critical of the data. Numbers may have inherent objectivity, but whose numbers are they? How are they generated? What are the sources for Smil’s data? Can these sources be trusted? Such are the deeper discussions that Smil’s book can foster, coupled with his own graphics and maps that students can consume online or generate themselves using WebGIS tools. The author states up front that “getting the facts straight” is “not as easy as it might seem” (xi). Indeed, in the epilogue, the author states, “Even fairly reliable—indeed, even impeccably accurate—numbers need to be seen in wider contexts” (307). This point touches on the essence of holistic geographic thinking that investigates changes over space and over time.


Another quality that should endear this blog’s readers to this book is the author’s statement that “we
must set the numbers in the appropriate contexts: historical and international” (xii). These contexts give the numbers meaning. This book will thus be useful for instructors because it weaves history with geography. As a coauthor of the book Spatial Mathematics: Theory and Practice Through
Mapping, I also believe this book will help students to evaluate maps and charts more carefully and realize that developing numeracy skills is important (Arlinghaus and Kerski 2014). Learning to derive and represent these numbers is a key skill for all data analysts.

Numbers Don’t Lie book.

References

Arlinghaus, S. L, and J. Kerski. 2014. Spatial mathematics: Theory and practice through mapping. New York: Routledge.


Gates. B. 2021. What sweat, wine, and electricity can teach us about humanity. GatesNotes. Accessed October 10, 2021. https://www.gatesnotes.com/Books/Numbers-Dont-Lie?WT.mc_id=20210803100000_
Numbers-Dont-Lie_BG-EM_&WT.tsrc=BGEM.


Monmonier. M. 2018. How to lie with maps. 3rd ed. Chicago: University of Chicago Press.

Numbers Don’t Lie: 71 Things You Need to Know about the World, by Vaclav Smil, New York, Penguin Press, 2020, 362 pp., Digital. (Paperback from $79.17). ISBN 9780143136224

Categories: Public Domain Data

The Questions Concerning Technology: The Case of Geotechnologies

August 15, 2022 4 comments

L.M. Sacasas reflects thoughtfully upon and writes about technology in society. One of Sacasas’ essays in particular in my judgment poses some good food for thought for those of us immersed in geospatial technology; the essay entitled The Questions Concerning Technology. These reflections and set of questions, wherein Sacasas updates his earlier post, are relevant and timely for the geotech community to frequently ask ourselves in our daily work. Along with these questions, it might be helpful to examine our posts about ethics, such as teaching about ethics, here, and reflections on Geoethics discussions, here. I invite you to examine all 41 of the questions, but in particular, those I list below. I have included my own comments in parens after many of the questions. For a video of these reflections, click here. With my thanks to the work that L.M. Sacasas is doing.

  • What sort of person will the use of this technology make of me? (See what I mean? Right away, a very insightful and thought-provoking question. What do I spend more time on and think about when I use GIS, and … perhaps even more important: What do I spend less time on?).
  • What habits will the use of this technology instill? (Am I talking and listening to people more or less than before? Am I managing the time I am given on this Earth effectively?).
  • How will the use of this technology affect my experience of time and place? (italics mine–since GIS is all about analyzing these two things, it only makes sense that we consider these. Plus, how will GIS affect how I interact with time and place? And, how does my own spatio-temporal framework affect my analysis?)
  • How will the use of this technology affect how I relate to other people? (This community has had several conversations around the way we communicate now digitally and virtually replacing much of our face-to-face interactions of the past. In addition, we have had a long history of sharing, geomentoring, and “giving back” to education and beyond).
  • How will the use of this technology affect how I relate to the world around me? (consider the action component of work with GIS: Are we using GIS just to gain more skills and knowledge, or does it lead to action in myself or in others, or both?).
  • What practices will the use of this technology cultivate or displace? (For example, am I getting into the field more or less than before? Am I using tangible manipulatives, or other tools, more or less than before?).
  • What will the use of this technology encourage me to notice or ignore? (From Pickles 1995 book Ground Truth to the present day, we have long been aware of the benefits but also the limitations of GIS analyses. Are we making strides in breaking through those limitations of GIS?).
  • What was required of other human beings so that I might be able to use this technology? (GIS people are sensitive to our impact on the planet, so this one seems to mesh well with our community. But do we think about this often?)
  • What was required of the earth so that I might be able to use this technology? (italics mine–overwhelmingly, GIS people think about the Earth all the time, so it seems like a natural fit, but this question adds a new element to our earth considerations).
  • How does this technology empower me? At whose expense? (The GIS community has in recent years become rightfully concerned about empowering those who have not had a voice, using GIS and maps).
  • Can I imagine living without this technology? Why, or why not? (Imagine for a moment if we had to go back to only using maps on physical media, or even the desktop-only GIS of the past).
  • How does this technology encourage me to allocate my time? (Interesting… what should we in the geospatial community spend more time on in the future? And that leads to — what should we spend less time on?).
  • Could the resources used to acquire and use this technology be better deployed? (Are we diversifying our community? Does GIS give those without a voice a voice? There are positive examples to be certain, but what else should we be doing?).
  • What possibilities for action does this technology present? Is it good that these actions are now possible? (I would argue that GIS has always been action-oriented, with a chief aim to build a healthier, more equitable, safer, more resilient world, but again, are these higher goals always in mind when we use the technology?).
  • What possibilities for action does this technology foreclose? Is it good that these actions are no longer possible? (We often discuss the opening of possibilities, but what about the closings? Are there any, what are they, and why do they matter?).
  • How does the use of this technology shape my vision of a good life? (What are my goals for my life and career? Am I really making a positive contribution to people and the planet?).
  • What limits does the use of this technology impose upon me? What limits does my use of this technology impose upon others? (Again, more insightful questions; I may not like to think about these things but they are important questions to ask!).
  • What assumptions about the world does the use of this technology tacitly encourage? (Our use of any set of tools, and science itself, is shaped by our world views and attitudes).
  • What knowledge has the use of this technology disclosed to me about myself and others? Is it good to have this knowledge? (As a place-based and increasingly personal technology, GIS has much potential to reveal things about ourselves and others. Do you share your fitness walks and runs for example? What else are you sharing–data, maps, apps, with whom, and why?).
  • What are the potential harms to myself, others, or the world that might result from my use of this technology? (See for example our essay, here: https://spatialreserves.wordpress.com/2020/03/22/potential-harm-from-geotagging-photographs/).
  • Upon what systems, technical or human, does my use of this technology depend? Are these systems just?
  • Does using this technology require me to think more or less? (Challenging! I and other geo-educators are always encouraging students to think beyond the click-click-click of learning tools, to really thinking critically about your data, methods, objectives, and much more. GIS has always been, first and foremost, a thinker’s tool, as I point out here).
  • What would the world be like if everyone used this technology exactly as I use it? (I think of Jack Dangermond’s vision of GIS becoming the “nervous system of the planet” enabling us to make smarter decisions).
  • Can the consequences of my use of this technology be undone? Can I live with those consequences?
  • Can I be held responsible for the actions which this technology empowers? Would I feel better if I couldn’t?

I look forward to your comments below.

–Joseph Kerski

Categories: Public Domain Data

Data Basin as a source for free and open geospatial data

August 1, 2022 Leave a comment

Data Basin is a very useful geospatial data portal with a focus on ecosystems and conservation. “A team of scientists, software engineers, and educators at the Conservation Biology Institute (CBI) built Data Basin with the strong conviction that we can expand our individual and collective ability to develop sustainable solutions by empowering more people through access to spatial data, non-technical tools, and collaborative networks” is the resource’s purpose.

Hence, Data Basin is more than just a data portal–it is a community. One feature of this community is the ability to create a free member account to connect with others. In addition, every free member account comes with a personal workspace, which is available in the far right of the navigation bar. Here a member can easily access content that the member contributes (datasets and documents) or creates in Data Basin.

It had been a while since I had last used Data Basin, and when I recently refreshed my experience with it, I was pleasantly surprised to see how it has evolved. It encompasses the modern GIS elements we have written about in this blog, including the ability to view the map in an interactive way, examine the data, review the metadata, and access the data. The search tool worked well for me, and the browse tool was useful. To download a data set, you need to register for the site and create a profile, but this took only 5 minutes for me to do.

A unique and wonderful feature of Data Basin is that content is not just available as maps and layers, but also in galleries and groups. Through these galleries and groups, one can more readily find related content; for example, in the fire data by category for Santa Barbara County, one can find a set of over 100 items, all directly tied to the theme of fire in that part of the world. In addition, gateways are sites powered by Data Basin and curated by members of various interest groups. They showcase spatial information for a particular geography, topic, project or organization. Gateways include a subset of the data available on Data Basin.

Data Basin showing the results of one data set.

Data Basin is not a new resource, but as we have not reviewed it for this blog, and given its longstanding utility among the scientific and education community, it is worthy of attention and of rigorous use. Consider using it for your next project!

–Joseph Kerski

Categories: Public Domain Data

An excellent example of a state imagery data portal

July 18, 2022 1 comment

I recently met with the developer of one of the finest imagery data portals I have ever seen, the LiDAR data portal for Indiana. With support from the state’s excellent IndianaView initiative and Purdue University’s Digital Forestry Initiatives, the LiDAR data portal is open to public and currently hosting the whole Indiana statewide LiDAR data collected in 2011-2013 and 2016-2020. It serves as a “virtual center” for (1) managing and sharing a massive volume of LiDAR data, (2) collaborating and interacting with other researchers and public via the portal without geographic limitations, and (3) communicating research findings to the public (see sample below). Also, since the creator of this portal serves as a GIS and civil engineering professor, this is an excellent example of the great results of collaboration, in this case, between government and academia.

Recent advancements in sensor technologies make it possible to collect fine spatial and high temporal resolution remote sensing data and automatically extract information in a high throughput mode. The state of Indiana USA has identified the need to have ubiquitous access to statewide topographic LiDAR covering all of Indiana, and Indiana recently finished 2nd statewide LiDAR data collection (1st statewide LiDAR data collection between 2011 – 2013 and 2nd statewide LiDAR data collection between 2016 – 2020). Topographic LiDAR is a surveying method that measures the distance to objects using a laser scanner to illuminate objects on or above the ground surface. Time of flights of the reflected light in combination with Global Navigation Satellite System (GNSS) and Inertial Measurement Unit (IMU) observations are used to make a highly accurate 3D digital representation of the earth’s surface. The resulting LiDAR 3D point cloud data can be further processed to generate accurate and reliable topographic information over large areas. Although Indiana statewide LiDAR data acquisition program collected valuable information, the massive data volume acquired over multiple years and lack of software packages customized for processing these data make it challenging to utilize its maximum potential use.

The LiDAR data portal was built up from scratch using Free and Open Source Software (FOSS) such as standard HTML/CSS and custom-developed JavaScript codes on top of other JavaScript libraries such as Leaflet and Potree for front-end development. The LiDAR data portal also provides TMS as a web service for Digital Terrain Model (DTM) and Normalized Digital Height Model (NDHM) so that users can display these layers in any GIS software packages. I encourage the reader to also investigate the UAV/Drone data hosted on the university’s Digital Forestry site for many areas of the state (see sample below).

The portal also includes the NDHM (Normalized Digital Height Model) data (see statewide example below).

RGB orthomosaic over Davis Forest: https://hub.digitalforestry.org/outbox/210604_p1_davis_PAC_120m_85_80_ortho_v2_clipped_se_corner_web.jpg [hub.digitalforestry.org]

Color Infrared orthomosaic over Davis Forest: https://hub.digitalforestry.org/outbox/210604_p4m_davis_PAC_140m_80_80_ortho_v2_se_corner_web.jpg [hub.digitalforestry.org]

Digital Surface Model over Davis Forest: https://hub.digitalforestry.org/outbox/210604_p1_davis_PAC_120m_85_80_dsm_v3_se_corner_web.jpg [hub.digitalforestry.org] (sample below).

I found the data portal extremely easy to use, fast and responsive, and rich with data and metadata. It is one of the best portals I have reviewed in the 10 years we have been writing this blog! I recently spent a week with the Indiana GIS community and as we wrote several years back, it (IGIC, or the Indiana Geographic Information Council and the Indiana GIS community) remains one of my favorite communities of practice, where government, academia, nonprofit, and industry work together in a collaborative spirit on mutual goals of enabling sound decision-making based on spatial data and methods. At the IGIC’s state GIS conference is where I learned about this portal–which speaks to the value of the community networking together in events like this for learning and collaboration.

For more about the developer of the Digital Forestry portal, contact Professor Jinha Jung at the Lyles School of Civil Engineering at Purdue University, and see the Geospatial Data Science Laboratory, here.

The Digital Forestry data portal interface.
Sample UAV imagery from the Digital Forestry data portal.
Indiana Statewide NDHM–Normalized Digital Height Model.

Digital Surface Model over Davis Forest.

–Joseph Kerski

Categories: Public Domain Data