The Need for a High-Accuracy, Open-Access Global DEM

With a proliferation of satellite data for environmental monitoring, ever advancing big data analytics methods, the availability of massive compute power, and last but not least, the Internet of Things, there ought to be no reason for still having to work with a global free DEM that is now reaching nearly 20 years of age and which, without applying smart and complex statistical methods to it, exhibits average errors in the vertical that are orders of magnitude greater than the accuracy needed in hazard modeling and prediction. For obvious reasons, this is a very unfavorable situation and thus this collection of articles makes a powerful case for a free and open-access high-accuracy DEM at the global scale. Such a resource would have game- changing impacts on applications ranging from weather prediction to food security and disaster response, and to many others. In this editorial opinion piece, we briefly discuss the various limitations of existing free global DEMs and outline the basic requirements and associated challenges of a global high-accuracy open-access DEM. Furthermore, we suggest a possible way forward to achieve this goal.