Tag Archives: ArcGIS
By Stephen K. Bryce, Esri Federal Government Expert
Since August 25, 1916, when President Woodrow Wilson signed the act creating the National Park Service, and continuing on through June 24, 2016, when the NPS added its 412th site, Stonewall National Monument, maps have communicated the importance of the nation’s most valued treasures. For a century NPS has created maps for survey, preservation, conservation, planning, tourism, search and rescue, facilities management, and more. Beginning its second century of custodial care, the NPS is modernizing web flows by bringing web GIS services into the mainstream of its map production.
The electromagnetic spectrum
In the early history of powered aircraft, aerial photographs—pictures of the earth from above—began to be found useful for military and scientific applications. Quite quickly, imaging professionals and scientists realized that it was possible to detect beyond what is visible to the unassisted human eye. Deeper and richer information could be revealed by detecting waveforms from beyond the rainbow of visible light, into the invisible. As it turns out, these hard-to-detect realms of the spectrum offered some of the most meaningful insights. Hidden in these signals were previously unknown facts about Earth that have enabled us to understand our world far more effectively than had been possible.
Multispectral imagery: Enabling extrasensory perception
One of the most extraordinary types of imagery collected by remote sensing is multispectral imagery. Each image is composed of data from a series of onboard sensors that collect small slices (or bands) across the electromagnetic spectrum. The table below shows the complete list of wavelengths (expressed as bands) that are collected by the Landsat 8 imagery according to what they capture. The images below are examples of what you “see” by combining different bands into red, green, and blue electronic displays or hard-copy prints.
The Natural Color (bands 4, 3, 2) combination of red, green, and blue is well suited for broad-based analysis of both terrestrial and underwater features and for urban studies.
Color infrared photography, often called false color photography because it renders the scene in colors other than those normally seen by the human eye, is widely used for interpretation of natural resources.
Land and water interface
Landsat GLS Land and Water Boundary (bands 4, 5, 3) emphasizes the edges between land and water.
This 6, 5, 4 band combination shows irrigated vegetation as bright green. Soils appear as tan, brown, and mauve.
Multispectral band combinations
Multispectral imagery measures different ranges of frequencies across the electromagnetic spectrum. One way to think of these different frequencies is as colors, where some colors are not directly visible to human eyes. These frequency ranges are called bands. Different image sensors measure different band combinations. The longest-running and perhaps most well-known multispectral imaging program has been Landsat, which began Earth image collection in the 1970s. By assigning data from three bands of the sensor to the red, green, and blue channels of an electronic display (or printer for a hard copy), color visualizations are created. Here are some examples of various alternate band combinations and their applications.
Panchromatic imagery, commonly known as pan, is typically recorded at a higher resolution than the multispectral bands on any given satellite. It remains a critical source for many GIS applications as a reference for basic interpretation and analysis. Pan is often combined with other bands through a process called pansharpening to generate higher-resolution scenes.
In the Agricultural band (combination 5, 4, 1) vigorous vegetation appears bright green, healthy vegetation appears as a darker green, and stressed vegetation appears dull green.
The Normalized Difference Moisture Index (NDMI) estimates moisture levels in vegetation where wetlands and vegetation with high moisture appear as blue growing to dark blue for higher moisture levels, and drier areas appear as yellow to brown shades. Image analysts often apply a formula to combine the selected multispectral bands to calculate various indexes.
This post is excerpted from The ArcGIS Imagery Book: New View, New Vision. Imagery is suddenly a big deal, and those who are adept at finding it, analyzing it, and understanding what it actually means are going to be in demand in the years ahead. The purpose of this book is to help everyone from GIS professionals to app developers, and web designers to virtually anyone how to become smarter, more skillful, and more powerful appliers of image data. The book is available through Amazon.com and other booksellers, and is also available at http://www.TheArcGISImageryBook.com for free.
By Raquel Perez
We are seeing the biggest humanitarian crisis of our time! Are you willing to answer the call to action?
World Humanitarian Day (WHD), August 19th, celebrates and recognizes humanitarian aid workers who risk their lives to improve the lives of others. This day was designated by the United Nations General Assembly to mark the anniversary of the 2003 bombing at the UN Headquarters in Bagdad, which killed 21 UN workers including Serio Vieira de Mello, the Special Representative of the Secretary-General to Iraq. See the story map to learn more!
Smart Communities Innovation Challenge Provides Support for Improving Mobile Government
Esri has partnered with measurement instrument manufacturer Leica to encourage innovation of mobile field data collection in government by offering grants totaling $143,250 in goods and services. Known as the Smart Communities Innovation Challenge, 10 governments that submit detailed project proposals demonstrating increased efficiencies in collecting data for decision support or improved productivity delivering governmental services will be selected to receive a grant.
Story Maps let you combine interactive maps and scenes with rich multimedia content to weave stories that get noticed. Here are some things you should consider when creating story maps.
Think about your purpose and audience
Your first step is to think about what you want to communicate with your story map and what your purpose or goal is in telling the story. Who is your audience? Are you aiming your story at the public at large, or a more focused audience, like stakeholders, supporters, or specialists who would be willing to explore and learn about something in more depth?
Spark your imagination
Go to the Story Maps Gallery to see some examples handpicked by the Esri Story Maps team to inspire you and highlight creative approaches. You can filter and search the gallery to check out how authors have handled subjects and information that may well be similar to yours. Explore. Get a gut feel for what makes a good story.
Northeastern University Student’s Smart Communities GIS App Spurs Vision for New Company
By Kurt Daradics
At the 2014 Esri User Conference (UC), Northeastern University civil engineering student Salar Shahini presented his work on a research project that used a GIS web-based application to constantly monitor roadway conditions. Jack Dangermond, president and founder of Esri, encouraged Shahini to pursue the application beyond the research phase and leverage Esri resources to commercialize the technology. Dangermond emphasized that innovative hardware and software technologies such as Shahini’s would provide an immediate positive impact in society and help communities become smarter.
Guided by Esri’s staff, Shahini and his advisors translated these thoughts into an ArcNews article, Constant Pavement Monitoring without Disrupting Traffic. The article triggered a myriad of emails from cities and states around the globe, making the team realize the true need and potential impact of the technology. The flood of responses encouraged them to found the company StreetScan.
Information gathered from a distance
Remote sensing—the acquisition of information from a distance—has had a profound impact on human affairs in modern history. This image of British Beach (the WWII code name for one landing spot of the June 1944 Normandy invasion) taken from a specially equipped US Army F5, reveals rifle troops on the beach coming in from various large and small landing craft. Seven decades later—even as its application has expanded to unimaginable reaches—remote sensing remains the most significant of reconnaissance and earth observation technologies.
Many platforms, many applications
Modern imagery is captured from a broad range of altitudes starting from ground level to over 22,000 miles above earth. The images that come from each altitude offer distinct advantages for each application. While not meant to be an exhaustive inventory, let’s take a look at some of the most commonly used sensor altitudes.
Flood season is upon us. Knowing ahead of time when a flood is going to happen, where flooding will occur, who will be affected, and how to respond is of great importance to reducing loss of life and property. Below you will find five story maps that show flood impacts and the damage each event had on life and property. These stories serve as reminders to plan ahead and be prepared for a significant flood event. Esri is partnering with communities, such as San Bernardino County, to mitigate the effects of flood events on lives and property.
This story map visualizes damage assessment data, including nonresidential and residential. The blue polygon represents the final flood extent, showing how the flood spread throughout Alexander County. Knowing what areas will be impacted is critical in preparing for a flood. According to the NOAA’s National Centers for Environmental Information (NCEI), the 2015 flood across Missouri, Illinois, and the Midwest had an impact of an estimated $3 billion (http://moneynation.com/u-s-floods-cost-34-billion/). Throughout this story map, you can see the flood extent in Cape Girardeau, Alexander County, Jersey County, and Peoria County. These images have helped ongoing research efforts for testing and developing standards.
Safe Communities Meet Up Features Senior Advisor to the White House, Program Lead from Department of Homeland Security
Law enforcement across the country are working to fulfill the President’s Police Data Initiative (PDI) to improve public trust and police legitimacy. GIS is an invaluable tool to help communities use open data to protect lives, property, and critical infrastructure. Esri has committed a vast amount of software and resources to help police departments across the nation access and understand information in order to keep communities safer.
The U.S. Department of Homeland Security’s Homeland Infrastructure Foundation Level Data (HIFLD) provides national foundation-level geospatial data that can be used to support community preparedness, resiliency, research, and more. Esri’s ArcGIS platform is the system that provides access to this information.
Esri Joins Americas Conference on Information Systems as Keynote Sponsor Discussing “The Age of the Location Platform”
By Christopher Cappelli
The annual Americas Conference on Information Systems (AMCIS) is one of the leading conferences presenting research by and for academics in the Information Systems and Technology field. The conference is organized by the Association for Information Systems (AIS), the premier professional association for individuals and organizations who lead the research, teaching, practice, and study of information systems worldwide.
At this year’s AMCIS, Esri will participate for the first time as keynote speaker and sponsor, representing its GIS software. As the world’s leading provider of GIS technology worldwide, Esri is happy to join AIS in educating and inspiring the next generation of IS and IT professionals.