Category: National Government
In countries like the United States and Germany, federal agencies keep careful watch on the nation’s rivers, and disseminate their observations to the public. But in developing nations, many of the world’s major rivers remain un-gauged, despite the millions of people whose lives depend on them. The Dartmouth Flood Observatory hopes to help solve this problem with a concept they call “satellite gauging sites,” which makes it possible to monitor the flowrate of rivers using freely available satellite data, without the need to build or maintain expensive infrastructure.
They key to this method is the microwave sensors carried aboard satellites like AMSR, TRMM, and GPM. As the amount of water on the landscape increases, emissions in the microwave spectrum decrease – a clear signal that can be used to track flowrate. Microwaves are unaffected by cloud, but absorbed by liquid water, which means that Flood Observatory scientists can monitor river conditions even when the ground is visibly obscured by weather.
The numerical estimates are much less accurate than ground-based gauging, of course, but still extremely valuable. As a relative estimate of how the flowrate is changing over time, they can be used to track droughts and floods, and to analyze long-term changes in the flow regime.
In order to make them more easily available to the GIS community, Esri has added these satellite gauging sites to the Live Stream Gauge map. When you click on one, it displays an estimate of today’s average flowrate, a description of the status (e.g. low flow, moderate flood, major flood), and a graph showing the time series. There is also a link to the station page, where you can get monthly and annual flow estimates, as well as some information about the calibration and accuracy of that particular site.
This latest update also included new contributions from England’s Environment Agency, the State of Nebraska, the State of Oregon, and the Iowa Flood Center – over 3000 new gauges in total – so if you haven’t checked it out in a while, now is a great time to take another look. For those of you who have been using this map, please let us know your thoughts about it in the comments. Thank you to all our stream gauge contributors!
Our user community has provided updates to the World Topographic Map! Contributing to Esri Community Maps is easy! This basemap release includes new Community Map contributions to the World Topographic Map. Areas with new and updated content include the country of Thailand and … Continue reading
We are excited to integrate Spain’s lidar derived elevation from Instituto Geográfico Nacional (IGN) into Esri’s World Elevation services (Terrain and TopoBathy). At 5 meters resolution (cell size), this update brings 6 times more details to Spain and a huge quality improvement over SRTM 1 arc sec … Continue reading
We continue to improve the World Imagery basemap with updates from DigitalGlobe and our GIS user community. This update features new and improved high-resolution imagery for areas covering most of Brazil, Saudi Arabia, and Denmark, parts of New Zealand and … Continue reading
Our User Community has updated Esri’s online basemaps with new and updated content. In fact, they have done it 18 times this year! This basemap release includes new Community Map contributions to the World Topographic Map. Areas with new and updated content … Continue reading
Contributions to ArcGIS Content Delivers Real-Time Data and Increases Government Efficiency “The make it once, use it many times model guarantees that our users have access to the most current data and it increases the efficiency among all levels of … Continue reading
Want to win your next election? In a new Learn ArcGIS lesson, you will learn how GIS could help you outmaneuver your rivals on the political battlefield.
In Map Voter Data to Plan Your Campaign, you will assume the role of a campaign manager researching voters for an upcoming election that includes southern Howard County in the U.S. state of Maryland. You will start the lesson by creating a map and geocoding a spreadsheet with the addresses of your potential voters. You will then download a layer of Tapestry Segmentation, developed by Esri as a way to classify American neighborhoods into 67 unique market segments based on a variety of demographic and socioeconomic characteristics. By researching Tapestry, you will learn more about the lifestyles and living standards of your voters as well as gain insight into their values and the issues they care about. Inferences could range from housing costs and college expenses to smartphone taxes and charity giving. Continue reading
Open Data and GIS improve forest management in the Congo Basin By Thomas Maschler and Asa Strong from World Resources Institute Open data enables citizens and communities around the world to engage in important societal and environmental issues. Besides stimulating … Continue reading
One year ago we published version 2 of the Civilian Topographic Map (CTM) which allows users to create 25K and 50K civilian style topographic data and maps using Esri Production Mapping. Today, we are pleased to announce the release of version 3.
Download ArcGIS Earth 1.3 now! ArcGIS Earth users can now do more with terrain, imagery, and KML in version 1.3, in addition to personalization and authentication improvements. Vertical Exaggeration Control In ArcGIS Earth 1.3, users will now see an on … Continue reading