Security, video, and cell phone cameras captured the terror in real time: frightened faces of people scrambling for safety or crouching under desks as buildings rocked and trees swayed during the magnitude 7.9 earthquake that shook Sichuan Province in May 2008.

Data collected through the China Earthquake Geospatial Research Portal (CEGRP) can be viewed and investigated by using a map service published by ArcGIS Server.

Even more disturbing pictures and video came later showing crumbled buildings and landslides: 69,197 people were confirmed dead and 374,176 people injured, according to Xinhua News Agency. Thousands are still listed as missing.

The images, however, only tell part of the story about what some call the Wenchuan, or great Sichuan earthquake. Scientists, scholars, and other researchers have started to collect seismic, environmental, geologic, and demographic data along with GIS datasets, layers, and maps related to the quake—some of it now appearing on the new China Earthquake Geospatial Research Portal (CEGRP) (cegrp.cga.harvard.edu) hosted at Harvard University.

On the CEGRP Web site, people will find links to free satellite imagery, GIS layers, tabular datasets, disaster recovery policies, and other reports. Some of the downloadable datasets include GIS layers in shapefile and KML file formats that show the epicenters of the earthquake and aftershocks; impact zones of the most severe seismic activity; the county boundaries that fall within the impact zones; and the estimated number of people killed by the quake, calculated by county-level districts. The site's visitors will also find a geologic map of Sichuan Province, the dams in the Chendu region, and power plants in China. More data is added as organizations and individuals contribute. Those that register on the site can also upload analyses or completed GIS datasets to share with other researchers, students, or colleagues.

"What we wanted to do is create a portal that becomes a place to go for sharing the data, as well as a permanent archive," says Merrick Lex Berman, the portal's developer.

Visitors to the CEGRP site can also visualize data online that's related to the quake by using the China Earthquake Map Service hosted by the Center for Geographic Analysis (CGA) at Harvard.

The site includes the CGA map service for visualizing data. Participants can use either the ArcGIS Server or the MapServer version. Berman says that the MapServer version is basically a data browser, while the ArcGIS Server version offers a lot more functionality. CGA staff monitors data submitted through the portal and selects spatial datasets to add to the map service periodically. Such datasets are symbolized in ArcGIS Desktop first and published through ArcGIS Server. Data additions and updates are done through ArcGIS Desktop (ArcMap) editing, and the changes are available to Web clients through a refresh of the ArcGIS Server map service within seconds.

This process gives the public users a quick yet well-symbolized preview of the datasets, allowing them to investigate the contents of each one, as well as relationships among different datasets. An example is the death toll per county. When displayed separately, the absolute number shows the total death count but not the percentage of deaths by population. But the data attribute table includes that information, which indicates more accurately the level of devastation to the local communities. For example, Mianzhu lost 11,098 lives, 2.15 percent of the total population, while Beichuan lost 8,605 lives, 5.36 percent of the total population. This data is available using the Identify function in the ArcGIS Server browser. The ArcGIS Server version allows end users to turn GIS layers off and on, search and zoom by place-name, query epicenters, investigate population and other attributes, and overlay county survey maps for selected counties. With the ArcGIS Server map service, the agency hopes users can obtain a general overview of the quake-affected area by browsing through the maps online and have a good understanding of the datasets before downloading them.

A Window into a Large Seismic Event

Public users can turn on and off various data layers; search and zoom to places by name; and examine population, casualty, quake intensity and impact zoning, local survey maps, and other regional or local data.

CGA and the Fairbank Center for Chinese Studies, also at Harvard, launched the CEGRP project two weeks after the temblor. Officials at the center and at CGA realized that sharing GIS data would assist organizations dealing with everything from disaster relief to reconstruction efforts. CEGRP will also help in scholarly research, as the data from such a large and devastating quake will be useful to urban planners, public health workers, environmental scientists, and others studying the seismic event, according to Berman. Fairbank Center for Chinese Studies officials agreed that the earthquake's significance from so many standpoints—from the sheer human tragedy to the science of the quake and from what the event will mean for China's economy to what role the catastrophe will play in politics in the future—meant it was worthy of a project to collect and share data about it.

"I think most big events in the news capture people's attention for a short time, and then they fade away," Berman says, "but the earthquake is going to have a large-scale impact on China and its economy for many years."

CEGRP, funded by CGA and the Fairbank Center for Chinese Studies, will provide scientists, decision makers, scholars, researchers, students, humanitarian and relief organizations, and the news media with access to downloadable and complimentary GIS data, imagery, and other information related to the quake. That data can then be integrated and analyzed using GIS software, leading to a greater understanding of many issues, including the seismic activity in China, past and present; the type of damage the earthquake and aftershocks have caused (such as massive landslides and the creation of quake lakes); the economic and environmental impacts of the disaster on the country; the health toll on the residents of Sichuan Province; and reconstruction plans in the devastated areas.

Although the Fairbank Center for Chinese Studies proposed the idea for a research project that focused on the Sichuan earthquake, CGA is spearheading it. "The center officials decided the geographic component is the one that ties everything together," Berman says, "so we turned over the project to Wendy Guan," research director at CGA. "Wendy really wanted to push forward quickly on the geospatial research side," he continues, adding that CEGRP will be a smart way to study the Sichuan earthquake and promote data sharing and problem solving, whether it's related to plate tectonics or public health.

"I don't know of any other Web sites that focus on trying to collect data specifically related to the earthquake and deliver it to anybody who is interested," says Berman. "I think it was a good decision to coordinate something that brings together all this information in one place."

Berman and Guan hope the data sharing will include information from academic and government sources within China. Guan observed that the Chinese government has shown a willingness to accept help from governments and organizations outside the country during the aftermath of this disaster, and perhaps the portal will lead to more international cooperation and data sharing, too.

"Our first objective is to promote information sharing," Guan adds, "and the second is to provide access to data that would trigger unique research projects related to the Sichuan quake."

Guan and Berman say those projects might be related to public health, such as studying the water quality after the quake, the psychological impact of the tragedy on the survivors, and building codes in quake-prone areas.

Seeking More Data

Almost daily, updates are posted to the CEGRP Web site with links to GIS layers, tabular datasets, satellite imagery, disaster recovery policies, papers related to the quake (including topics such as landslides), announcements of symposia and calls for papers about the earthquake, and related reports. Registered members are encouraged to send FTP files to the CEGRP server for distribution and archiving on the CEGRP portal.

CEGRP also posts news articles related to the quake from media outlets, such as the Associated Press, the Christian Science Monitor, the New York Times, Reuters, and Xinhua News Agency. "I have several aggregators running that pluck out articles specific to the earthquake,'' Berman says. Examples include an article published in the International Herald Tribune by Boston Globe writer Drake Bennett, "Do Natural Disasters Stimulate Economic Growth?"

More Information

For more information, contact Merrick Lex Berman, CEGRP developer (e-mail: mberman@fas.harvard.edu), or Wendy Guan, Ph.D., director of GIS Research Services, CGA (e-mail: wguan@cga.harvard.edu, tel.: 617-496-6102).

See also "GIS Enhances China Relief Efforts."