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Digital Cities: The Hudson Yards Project

December 29, 2015 Leave a comment

The Hudson Yards project is not only one of the largest real estate development projects in the USA but also one of the largest city-wide data collection projects. To facilitate this data capture, a significant component of the project is a new digital infrastructure that will track human behaviour on an unprecedented scale.

Working with a number of technologies previously used for mapping and monitoring more remote locations, in conjunction with a myriad of sensors, cell phone and wifi technology, the project designers and planners aim to capture data everyone is interested in – pollution levels, water usage, traffic, retail patterns and much more.

 

One of the contributors makes an interesting point about the project having access to a range and quality of data not currently available from public data sources but didn’t elaborate on whether the public would also have access to some or all of this data.

Landsat Thematic Bands Web Mapping Application in ArcGIS Online

December 20, 2015 2 comments

Teaching remote sensing?  Or just want to understand remotely sensed imagery better?  The Landsat Thematic Bands web mapping application can serve as a very useful teaching, learning, and research tool.  It covers the entire planet and the map is updated daily with new Landsat 8 scenes.

You can access many band combinations and indices by hovering over the tools to the left of the map image and selecting among the following:

  • Agriculture: Highlights agriculture in bright green. Bands 6,5,2
  • Natural Color: Sharpened with 25m panchromatic band. Bands 4,3,2+8
  • Color Infrared: Healthy vegetation is bright red. Bands 5,4,3
  • SWIR (Short Wave Infrared): Highlights rock formations. Bands 7,6,4
  • Geology: Highlights geologic features. Bands 7,4,2
  • Bathymetric: Highlights underwater features. Bands 4,3,1
  • Panchromatic: Panchromatic image at 15m. Band 8
  • Vegetation Index: Normalized Difference Vegetation Index (NDVI). (Band5-Band4)/(Band5+Band4)
  • Moisture Index: Normalized Difference Moisture Index (NDMI). (Band5-Band6)/(Band5+Band6)

The Time tool for different indices at larger scales based on a user-selected location enables examination of changes over years or over seasons.  It also provides temporal profiles for NDVI (Normalized Difference Vegetation Index), NDMI (Normalized Difference Moisture Index) and an Urban Index, dating back to 1973.  The Identify tool enables access to information on the date, cloud cover, and a spectral profile about each scene.  The Bookmark tool allows access to interesting locations such as the “Eye of the Sahara” in Mauritania.

The application is written using Web AppBuilder for ArcGIS accessing image services using the ArcGIS API for JavaScript, with access to the following Image Services:

  • Landsat Multispectral on AWS – 8-band multispectral 30m resolution image services and functions that provide different band combinations and indices.
  • Landsat Pan-sharpened on AWS – Panchromatic-sharpened imagery; 4-band (Red, Green, Blue and NIR); 30m resolution.
  • Landsat Panchromatic on AWS – Panchromatic imagery; 15m resolution.

These services can also be accessed through the public Landsat on AWS group on ArcGIS Online.  Because you can add these services as layers to your own maps or are adding to maps made by others, or if you are simply using the above web mapping application as a standalone map, you truly have “the world at your fingertips” with these maps and apps.  But there is a third option: Use the Unlock Earth’s Secrets page, also useful for instruction, with the above application embedded in it, but also with explanatory text and featured places around the planet as they have changed through time.

Think of the above as solid introductory segments to help your students, customers, or stakeholders see the value in remote sensing.  These maps and applications require very little geospatial technology skills to use, but allow you to focus on building remote sensing concepts and principles while exploring some truly engaging content and places.

To dig deeper, delve into the many powerful remote sensing functions available in ArcGIS Desktop.  One source for engaging, hands-on activities, is Kathryn Keranen and Bob Kolvoord’s book Making Spatial Decisions Using GIS and Remote Sensing:  A Workbook.

Give these resources a try!

Landsat web application

Landsat web application in ArcGIS Online.

Sentinel-2 Imagery Now Available

December 14, 2015 1 comment

Earlier this year we wrote about the launch of the European Space Agency’s (ESA) Sentinel-2A satellite and the mission to deliver a range of data products including land cover maps and bio-geophysical data. ESA have just released the Sentinel-2A orthorectified products, which are now available to download for free from the Sentinel-2 Data Hub https://scihub.copernicus.eu/s2/.

Sentinel-2a Data Hub

Sentinel-2a Data Hub

ESA have also posted a data quality report to document the current status of the data and provide information on product formats and features. As the programme is currently in a ramp-up phase, further improvements in the extent of coverage and the accuracy of the products are expected over the next few months.

Open Data Sharing for Earth Observations: The Global Earth Observation System of Systems (GEOSS)

December 6, 2015 1 comment

Data discover-ability, accessibility, and integration are frequent barriers for scientists and a major obstacle for favorable results on environmental research. To tackle this issue, one that is raised in our book and in this blog, the Group on Earth Observations (GEO) is leading the development of the Global Earth Observation System of Systems (GEOSS), a voluntary effort that connects Earth Observation resources world-wide, acting as a gateway between producers and users of environmental data.

Barbara Ryan, Director, GEO Secretariat, says that, “The primary goal is the assurance of Earth observations so that we can address society’s environmental problems. While many of our activities are targeted toward monitoring global change, we’re actually more concerned about the assurance, continuity, sustainability and interoperability of observing systems, so that monitoring across multiple domains can be done. Governments, research organizations and others actually do the monitoring. We just want to make sure that the assets are in place, and that the data from these monitoring efforts is shared broadly. One of GEO’s primary objectives is to advocate broad, open data sharing, particularly if the data was collected at taxpayer expense—the citizens of the world should have access to that information”

“In this regard, during the first part of GEO, 2004-2009, we looked at the GEO mission as a massive cataloging effort. Then, about two years ago, we changed strategies. We transitioned to a brokering approach whereby interoperability agreements were established with institutions that have datasets and/or databases, rather than us seeking out individual datasets. An example of this approach is illustrated with our agreement with the World Meteorological Organization (WMO). WMO
members have generally registered their data in the WMO Information System (WIS). So we worked on an interoperability arrangement between GEOSS and the WIS resulting in data from one system being discovered by the other system. We are now hearing, particularly from some members in the developing world, that they are getting access to information that they didn’t know existed.”

“WMO members are getting biodiversity and ecosystem information that wouldn’t normally be delivered through the WIS that focuses on weather, climate and water, and GEO members are gaining increased visibility to information in the WIS. It’s a win-win story, and we’d like to have interoperability brokering agreements with any institution that wants its environmental information broadly viewed and accessible throughout the world.”

“Many of the 25 countries that produce 80% of the world’s crops have global forecasting capabilities. GEO is advocating that information from these countries be shared more broadly and openly, and that algorithms be harmonized so that forecasts are improved around the world. Global transparency will help create more stability and a more food-secure world.  A related aspect of the security issue is that governments do not want another government having easy access to what is happening over their domain with the fear that this information will be used against them. While this concern is recognized, most of the information that GEO is interested in transcends national boundaries. Atmospheric, oceanic and many terrestrial processes do not respect national boundaries, and actions in one part of the world often have wide-spread consequences. The benefits of broader data sharing almost always outweigh the risks associated with not sharing data.”

These are welcome words to us here as authors of Spatial Reserves and also most likely will be welcome words for the entire geospatial community. I look forward someday soon to be able to search for and use data using the GEOSS.

The Group on Earth Observations (GEO) is leading the development of the Global Earth Observation System of Systems (GEOSS)

The Group on Earth Observations (GEO) is leading the development of the Global Earth Observation System of Systems (GEOSS).