Remote sensing is not an especially recognized scientific discipline, at least in comparison to fields like biology, chemistry, or medicine.
From its beginnings with aerial photography in the 1920s through the initial stages of satellite-based land imaging in the early 1970s, few peer-reviewed publications were available for scientists to share their ideas and improve their methods. The rise of rigorous peer review in the 1970s through publications like Remote Sensing of Environment (RSE) helped advance the discipline, with leaders such as RSE’s longtime editor Dr. Marvin Bauer serving as guides and gatekeepers.
In time, space-based remote sensing moved from emergent technology to a critical component of our understanding of Earth. In a recently published podcast, Marv—a professor emeritus of remote sensing at the University of Minnesota, and the 2010 William T. Pecora Award honoree by the USGS and NASA—talked about the importance of his field of science and its place in our global society.
As the longtime editor of RSE, what were your goals for that journal?
“Its goal has been to publish papers with new and significant results that advance scientific knowledge and applications. These are the papers that will be read, cited, and used. My observation as a researcher, as well as editor, is that science is not advanced by publishing weak papers. High standards and rigorous peer review have been two important and continuing aspects of RSE’s philosophy and approach that I followed, and I think led to its success.”
How critical are peer reviews to the legitimacy and value of science that’s being done, and to its applications?
“Rigorous peer review is the hallmark of scientific journal publication in all fields, including remote sensing. It’s absolutely critical to evaluating the soundness and validity of research. Reviews assist editors in determining whether the contribution and merits of submitted papers meet the journal standards and are sufficient for journal publication ... They also help authors improve their papers and strengthen their research. Without rigorous peer review, the credibility of results is compromised. The best authors expect and appreciate critical evaluation of their papers before they are published. Rigorous peer review and high journal standards lead to well-cited papers that help other researchers and advance the field.”
Why are peer reviews blind, and might exposing the names of those reviewers lead to greater accountability?
“There are exceptions, but most journals use a blind review process in which the reviewers’ names are not identified. I do not see much, if any, advantage, to identifying reviewers’ names. Indeed, I suspect it would discourage many reviewers from agreeing to do a review and providing their candid thoughts.”
What is your experience in how authors deal with criticism?
“Some authors do resist criticism of their paper, but most appreciate constructive criticism that identifies problems or limitations and provides constructive comments on how to improve the paper—and possibly the research. I found the best way to avoid criticism of reviews was to select reviewers whose experience and research interest were well matched to the topic of the paper, and whose expertise was evident from their reviews. Most authors expect serious reviews of their paper, but they may also disagree with some points in reviews and rebut them while revising the paper. But criticisms need to be taken seriously. Or, if a paper has been rejected, it’s OK for an author to request—with good arguments—reconsideration of a decision or an additional review or two. I never thought my decisions were infallible, and sometimes a paper that was initially rejected was not only accepted, but well cited … a positive outcome.”
How about the role the reviewer plays?
“It goes without saying that authors are essential to any journal, but so are the reviewers. Their evaluations of the strengths, weaknesses, and contributions of the research and recommendations are invaluable to the editors in determining which papers to accept, which not to publish, and needed revisions of those that have the potential to be accepted. Reviewers who recognize the importance of journal publication and the peer review process and are willing to contribute their time and expertise in reviewing their colleagues’ papers, are critical and play a vital role.”
As you look at the practices of other remote sensing or environmental journals, are there trends that you see that help or hurt the effort to ensure the integrity of the scientific literature?
“When RSE began in 1969, it was the third remote sensing journal. Today there are more than 20. It is quite appropriate and good that the number of journals has increased as the technology, science and applications of remote sensing have increased, but I question whether our field needs or has been well served by all of the current journals, some with very similar descriptions to other well established journals. Why do I say that? In the 2018 Journal Citations Report, the statistics showed that the top 10 journals by impact factor published 83 percent of the papers and had 93 percent of the citations. Although not quantified like the JCR statistics, I worry that some journals are emphasizing speed to publication over peer review and filling journal pages. My concern is that a rejection by RSE or one of the other strong journals no longer means the paper will not be published, because there’s always another journal wanting to fill its pages that will accept it.”
As an early member of the Laboratory for Applications of Remote Sensing (LARS) at Purdue University, you were part of a lab that was instrumental in establishing and pushing the state-of-the-art in quantitative remote sensing, right?
“I had the good fortune to join LARS as a research agronomist in June of 1970 as Landsat 1 was being built. I was impressed when I was interviewed about its role in defining the Landsat plans, its research on computer-aided processing and classification of multispectral data, and the potential for applications, including crop inventory. Two months later, there was a major epidemic of southern corn leaf blight, and we were asked by NASA to look at monitoring its extent and severity in Indiana with digital multispectral data and color IR photography. The results were positive and led to the Corn Blight Watch Experiment in 1971 that put together all of the components of a system to acquire and analyze imagery to monitor its spread and severity across seven corn belt states. LARS had a major role in that project, and then in classification of the first Landsat digital image in July 1972. And subsequently many more in its work with NASA, USDA and other agencies.”
Colleagues have said that you are an unabashed fan of Landsat. Why is that?
“I have often told students and others that Landsat is my favorite sensor. One, because it was being built as I started my career in remote sensing, but more importantly for the capability it has provided for almost 50 years to acquire important information about environment and natural resources. The advancements in its spatial, temporal and spectral-radiometric resolution, new biophysical and radiometric models and processing and classification algorithms, along with faster and cheaper computers and the internet, are providing more detailed, more frequent, and more accurate information for mapping, monitoring, and analysis of Earth resources and environment.”
What’s your assessment of the role Landsat has played in improving our stewardship of the Earth’s natural resources?
“In short, it has been huge. Landsat data are being used for many applications and by many countries. A very important change in the Landsat program was when the data were made available at no-cost by USGS and the EROS Center. It greatly expanded the R&D and applications around the world. It is enabling a paradigm shift from change detection to monitoring with the promise of near real-time monitoring. I am looking forward to the launch of Landsat 9 next year and to the systems that follow it.”
What has the push for peer-reviewed studies and peer-reviewed literature done to the discipline of remote sensing science? Has it legitimized it even more?
“Peer review added to its credibility. When I started in remote sensing, and for about almost 10 years, there were some major international remote sensing conferences that attracted a good number of people and a large percentage of those working in the field at that time. Large volumes of their proceedings were published. I remember carrying home about 20 pounds of proceedings from one of those symposia. There was lots of good work in those papers, but in reality, that was gray literature, not peer reviewed. Because it’s gray literature, not in the journals that are archived in libraries and are maintained over time, a lot of that was lost. I think the peer review in journal publications began to become more recognized as, ‘That’s absolutely critical. Our discipline, remote sensing, needs to be doing that like some of the other major disciplines, chemistry, physics, mathematics and many more.’ So, I think that was very good.”