Posts Tagged ‘arcuser’

The Accuracy and Precision Revolution: What’s ahead for GIS? (Nighbert via ArcUser)

Wednesday, April 7th, 2010

acc_precis_5-lg

[Editor’s note: “As we try to integrate highly resolved data into existing GIS, the errors in legacy data will become more apparent.” Jeff outlines the problem through his experience at the BLM in Oregon. Jeff is also responsible for early “bump mapping” of digital terrain models (DEMs).]

Republished from the ESRI ArcUser Winter 2010.
By Jeffery S. Nighbert, U.S. Bureau of Land Management

The ability to obtain precise information is nothing new. With great patience and skill, mapmakers and land surveyors have long been able to create information with an impressive level of accuracy. However, today the ability to determine and view locations with submeter accuracy is now in the hands of millions of people. Commonly available high-resolution digital terrain and aerial imagery, coupled with GPS-enabled handheld devices, powerful computers, and Web technology, is changing the quality, utility, and expectations of GIS to serve society on a grand scale. This accuracy and precision revolution has raised the bar for GIS quite high. This pervasive capability will be the driver for the next iteration of GIS and the professionals who operate them.

When I say there is a “revolution” going on in GIS, I am referring to the change in the fundamental accuracy and precision kernel of commonly used geographic data brought about by new technologies previously mentioned. For many ArcGIS users, this kernel used to be about 10 meters or 40 feet at a scale of 1:24,000. With today’s technologies (and those in the future), GIS will be using data with 1-meter and submeter accuracy and precision. There are probably GIS departments—in a large city or metro area—where this standard is already in place. However, this level of detail is far from the case in natural resource management agencies such as Bureau of Land Management (BLM) or the United States Forest Service. But as lidar, GPS, and high-resolution imagery begin to proliferate standard sources for “ground” locations, GIS professionals will begin to feel the consequences in three areas: data quality, analytic methods, and hardware and software.

Continue reading at ArcUser . . .

The Importance of Building Geospatial Infrastructures (ESRI)

Tuesday, April 21st, 2009

[Editor’s note: Having a consistent set of quality geospatial databases enables cartographers and GIS professionals to focus on moving projects forward, avoiding costly database re-creation. Sharing the same base data across multiple projects and multiple organizations allows interoperability effeciencies and synergized results. Tom Patterson, Dick Furno, and I are working together to build a vector complement for Tom’s Natural Earth world raster landcover data at 1:15,000,000; 1:50m; and 1:110m scales. We hope these new shapefiles will play an important role in the community to create a small-scale (world, continental, and regional) geospatial infrastructure.]

Republished from ESRI’s ArcUser.
March 2009 article also available in PDF format.

Like no other time in recent history, our world is challenged. Disease, environmental deterioration, disasters, and now the widespread disruption of financial markets test the resourcefulness of society.

Over the past 40 years, GIS has evolved from a tool for managing projects to a framework for understanding and responding to problems on scales ranging from the local to the global. The geographic approach has become an important methodology for integrating data and information and enabling better decision making. The availability of quality geospatial data, together with improvements in software and hardware performance, has made these advances possible.

click to enlarge
The Solar Boston Web site uses geospatial data and high-performance, application-focused Web mapping to encourage the adoption of solar energy in the city of Boston, Massachusetts. Visitors can use tools at the site to calculate the solar potential of building rooftops and the annual cost savings that could be realized from installing solar panels.

With the move to an object-oriented platform, ArcGIS is better able to abstract and model the world, representing and integrating information about complex systems and modeling their behaviors. This is true whether the subject under study is as broad as an ocean or limited to a neighborhood.

The development of spatial data infrastructures (SDIs) represents the next logical step in the expansion of GIS use for data management and decision support. SDIs use accepted data and metadata standards in the creation of well-documented foundation datasets. Used with constantly updated operational data, SDIs make data more accessible and useful for specific tasks and analyses and save time while sharing costs. SDIs, together with GIS software, unlock the information contained in the terabytes of measurements, images, transactions, and other data stored in digital form by placing it in a geographic context.

The phenomenal growth of the Internet has multiplied the value of SDIs by enhancing the dissemination of data and information products. The newest release of ESRI software, ArcGIS 9.3.1, is focused on making information more consumable using the Internet. It supplies tools for configuring and deploying responsive and informative Web maps that help users accomplish specific tasks.

In February 2009, the Statistical Office of the European Communities (Eurostat) awarded a contract for the development of the technical components of a Web-based GIS. The contract went to a consortium that based its solution on ESRI technology.

These components will comply with the provisions of the Infrastructure for Spatial Information in Europe (INSPIRE). In establishing INSPIRE, the European Commission recognized the importance of quality georeferenced information to the understanding of the complex interactions between human activities and environmental pressures and impacts.

Two articles in the Focus section of this issue of ArcUser magazine provide additional examples of the value of building geospatial infrastructures to address complex problems and provide tangible benefits.

Maintaining water quality is essential to the health of the environment. Although water quality monitoring has been ongoing for decades, this abundance of measurement data cannot be translated into effective regulation and remediation action if it is not accessible, placed in geographic context, and amenable to analysis.

With new tools in ArcGIS, such as the regression analysis tools, vast data inventories can be placed in a geographic context and analyzed. This scatterplot matrix diagram is used for exploring data on foreclosures to discover if there is any relationship between variables preparatory to effectively modeling it.

The staff of Region 4 of the U.S. Environmental Protection Agency developed a geodatabase that manages current and historical water quality data and allows for rapid and flexible inquiry, analysis, and dissemination of this data and the information derived from it. This geodatabase, loaded into an ArcSDE server, uses feature classes, reformatted tables, and relationship classes. Information can be viewed as layer files generated from query definitions or queried by feature. This information is available from the desktop or distributed as ArcReader projects.

The benefits accrued from a geospatial infrastructure are greatly multiplied at larger scales as demonstrated by the marine SDI developed by the Portuguese Instituto Hidrografico. The SDI created by this naval organization integrates an abundance of sea monitoring data, prediction data, navigation charts, and base data using international data format standards and data models. A fully stipulated data policy and metadata for all geospatial data ensure data quality and promote data reuse. A wide range of information products generated for public, private, and military use are widely disseminated through Web portals. In addition, the SDI provides ad hoc decision support for the navy.

As these articles show, GIS professionals will play a more important role than ever in helping understand complex systems. With the development of SDIs, GIS professionals will be better able to apply GIS to transform data into knowledge. Aided by increasingly powerful tools in GIS, they can gain a better understanding of the world’s complex systems and help develop a more sustainable future.

Related ESRI article:

A Geospatial Foundation: Public, private, and military applications flow from SDI

Tutorial for ArcGIS web mapping API for JavaScript (ESRI)

Tuesday, February 10th, 2009

[Editor's note: This tutorial from ESRI walks the user thru a short project using the new ArcGIS web mapping API for Javascript.]

Republished from ESRI ArcUser magazine.
Winter 2009. View code snippits.
List of sites using ArcGIS API for Javascript.

Add a Map to a Web Page in Three Simple Steps
Getting started with the ArcGIS API for JavaScript

By Bronwyn Agrios, ESRI Education Services

Giving a wider audience access to your geographic data and maps through a Web page is almost effortless when you embed a simple map into a new or existing Web site using the ArcGIS API for JavaScript. Although ArcGIS Server provides many methods for adding a spatial component to a Web site, the ArcGIS API for JavaScript lets you use ArcGIS Server services to build lightweight, high-performance, pure browser GIS applications. ArcGIS API for JavaScript is hosted by ESRI and free to use. There are no licensing or service fees associated with its use.

Use the ArcGIS API for JavaScript to embed a map or perform a task such as querying spatial data in your Web application. The best way to get started using the ArcGIS API for JavaScript is to use the application samples and services provided by ESRI. If needed, you can modify these samples to include your own services and custom functionality in a mashup that incorporates multiple layers and functionalities in a single application.

This tutorial shows you how to access ArcGIS Online services through a simple Web application created using the JavaScript API. ArcGIS Online is a family of Web-based services and resources that lets you populate applications with base data hosted by ESRI and access tasks. In this exercise, you will be using only spatial content from ArcGIS Online in a JavaScript API application so you won’t even need to set up and maintain an installation of ArcGIS Server.

The Flagler County Property Appraiser Web site used the ArcGIS API for JavaScript to create an application that helps citizens find real property information including land, building, assessed, and taxable values.

Step 1

Embedding a Hosted Map in a New Web Page To create a Web page that contains an embedded map from a hosted service, you do not need to have ArcGIS Server installed or possess mapmaking or programming skills.

The following section will help familiarize you with the ArcGIS API for JavaScript samples on the ArcGIS Server Resource Center that you can use to create this page.

ArcGIS Resource Centers provide you with one-stop access to help resources, blogs, communities, and other information on all ArcGIS products. Navigate to resources.esri.com and select ArcGIS Server or any other
products. To learn more about the available samples, you will make a local copy of some sample JavaScript code and make it available through a new hosted Web page using the following steps:

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