Spacetime maps visualize travel time by distorting geographical maps. Instead of showing distances, these maps warp space so that the distance to any point represents the time it takes to travel there from a chosen origin. Faster travel methods result in less distortion, while slower methods exaggerate distances. The map demonstrates how travel time, rather than physical distance, shapes our perception and accessibility of different locations. It allows users to select various transportation modes (car, walking, public transit) and adjust the starting point to explore how travel time changes the perceived world.
The blog post explores whether the names of lakes accurately reflect their physical properties, specifically color. The author analyzes a dataset of lake names and satellite imagery, using natural language processing to categorize names based on color terms (like "blue," "green," or "red") and image processing to determine the actual water color. Ultimately, the analysis reveals a statistically significant correlation: lakes with names suggesting a particular color are, on average, more likely to exhibit that color than lakes with unrelated names. This suggests a degree of folk wisdom embedded in place names, reflecting long-term observations of environmental features.
Hacker News users discussed the methodology and potential biases in the original article's analysis of lake color and names. Several commenters pointed out the limitations of using Google Maps data, noting that the perceived color can be influenced by factors like time of day, cloud cover, and algae blooms. Others questioned the reliability of using lake names as a proxy for actual color, suggesting that names can be historical, metaphorical, or even misleading. Some users proposed alternative approaches, like using satellite imagery for color analysis and incorporating local knowledge for name interpretation. The discussion also touched upon the influence of language and cultural perceptions on color naming conventions, with some users offering examples of lakes whose names don't accurately reflect their visual appearance. Finally, a few commenters appreciated the article as a starting point for further investigation, acknowledging its limitations while finding the topic intriguing.
Mercator: Extreme pushes the boundaries of the web Mercator projection by visualizing the entire world map at incredibly high zoom levels, far beyond traditional map applications. It demonstrates the inherent distortion of Mercator as landmasses become increasingly stretched and warped, especially near the poles. The project uses custom tiling and rendering techniques to handle the immense detail required for such extreme zoom levels and allows users to interactively explore this unusual cartographic perspective.
Hacker News users discuss the extreme Mercator projection, mostly focusing on its comedic distortion of landmasses at higher latitudes. Some commenters appreciate the project as a clear demonstration of how Mercator's cylindrical projection stretches areas away from the equator. Others highlight the educational value, contrasting it with the common misconception of Greenland's size relative to Africa. A few users suggest alternative visualizations, such as a globe or comparing the distorted areas to their true size on a map using different projections. One commenter notes the inherent difficulty in accurately representing a sphere on a flat surface, while another points out the project creator's other interesting work. There's also brief discussion of the historical context and usage of Mercator projections, including its suitability for navigation.
Esri has released the USA Hydro Network v1.0, the most detailed open map of US surface water ever created. Derived from the 3D Elevation Program's 1-meter resolution data, this hydro network boasts unparalleled accuracy and granularity, providing a much clearer picture of water flow compared to previous datasets. It features over 100 million flowline segments and includes detailed information on flow direction, stream order, and watershed boundaries, offering valuable insights for applications like hydrologic modeling, environmental management, and infrastructure planning. The data is freely available for download and use.
HN commenters generally expressed enthusiasm for the detailed water map, praising its visual appeal and potential uses for conservation, research, and recreation. Some raised concerns about the map's accuracy, particularly regarding ephemeral streams and the potential impact on regulatory determinations. A few commenters discussed the underlying data sources and technical aspects of the map's creation, including its resolution and the challenges of mapping dynamic water systems. Others shared links to related resources like the National Hydrography Dataset (NHD) and other mapping tools, comparing and contrasting them to the featured map. Several commenters also highlighted the importance of accurate water data for addressing various environmental challenges.
Summary of Comments ( 3 )
https://news.ycombinator.com/item?id=43040986
HN users generally praised the map's concept and execution. Several appreciated its ability to visualize travel time in a novel way, highlighting the dominance of air travel over geographical distance in modern times. Some pointed out interesting details revealed by the map, such as the relative isolation of Australia and New Zealand. A few users suggested potential improvements, like the inclusion of high-speed rail lines, ferry routes, and more granular city-level data. There was also discussion of the projection used and its potential distortion effects. Finally, some comments offered alternative methods for visualizing similar data, referencing existing tools or suggesting different approaches.
The Hacker News post "Spacetime maps: A map that warps to show travel time," linking to maps.vvolhejn.com, generated a modest amount of discussion, with a handful of comments exploring different facets of the concept and its implementation.
Several commenters appreciated the visualization and its novelty. One user described it as "pretty neat," highlighting how it effectively illustrates the impact of geographical features and transportation infrastructure on travel time. Another commenter praised the interactive nature of the map, noting the ability to drag the destination point and observe the resulting distortions in real-time. This interactivity, they suggested, makes the concept more engaging and understandable.
The discussion also touched upon the practical implications and potential applications of such maps. One user pondered the usefulness of incorporating this kind of visualization into standard mapping applications, suggesting it could be valuable for urban planning and logistics. Another commenter pointed out the existing use of similar concepts in isochrone maps, which depict areas reachable within a given time frame. This prompted a brief comparison of the spacetime map to isochrone maps, with some users noting the spacetime map's more visually striking presentation of the same underlying data.
A few commenters delved into the technical aspects of the map. One user questioned the specific algorithm employed to calculate travel times and suggested an alternative method. They speculated on the use of Dijkstra's algorithm or A* search, highlighting the complexities of accurately modeling real-world travel conditions. Another user inquired about the data source used for the map, recognizing the importance of accurate and up-to-date information for generating meaningful visualizations.
While generally positive, the comments also acknowledged limitations. One user pointed out the current focus on driving times, suggesting the inclusion of other modes of transportation like public transit would enhance the map's utility.
Overall, the comments on the Hacker News post reflect a general appreciation for the innovative approach to visualizing travel time, coupled with a pragmatic discussion of its practical applications, technical underpinnings, and potential areas for improvement.