(Los Angeles Times Op-Ed Commentary, 11/14/1999)
If there has been a certain apocalyptic feeling to the spate of recent earthquake activity worldwide, rest assured--it sometimes feels that way to the earth sciences community as well. That is, while earth scientists don't see recent worldwide activity as any sort of biblical harbinger, it has left the community reeling, having had to deal with the scientific and media response to four significant earthquakes in such close succession.
However, the world is not coming to an end. The earth has been around for a few billion years and doesn't care that, according to a modern calendar, we're about to click over to a nice, round number. In fact, globally speaking, 1999 is shaping up to be a slow year for earthquakes. While the planet experiences 15-20 events of magnitude 7.0 or greater in an average year, we have seen only seven so far in 1999. This number includes the recent events in Turkey, Taiwan, Mexico, and California, as well as three events in remote regions of the South Pacific.
Recent activity is somewhat unusual in that so many of the M7+ earthquakes have struck near populated areas, but we know this is only a matter of statistics. And as we head into a new millennium with the global population at six billion and counting, the odds can only continue to worsen against us. Along the Pacific Rim--the so-called "Ring of Fire"--virtually all major cities are vulnerable to earthquakes of magnitude 7 and larger.
In southern California, the southern San Andreas fault has been considered "10 months pregnant" for a long time, and earth scientists have been carefully monitoring a series of small earthquakes near the southern end of the San Andreas that seem to have been triggered by the recent Hector Mine earthquake. The chance of a subsequent large earthquake is still considered low, but, at the same time, you don't have to be a seismologist to know that one can't stay 10 months pregnant forever.
Fortunately, where earthquakes and earthquake hazard are concerned, the new millennium is heralding tremendous opportunities as well as tremendous challenges. The recent M7.1 Hector Mine earthquake has been dubbed the first "cyberquake" because it is the first substantial earthquake to have struck southern California since the installation of the new, state-of-the-art Trinet seismic network. A collaborative effort between the U.S. Geological Survey, Caltech, and the California Divisions of Mines and Geology, the Trinet array provides more, better, and faster seismic data than has ever been available before. We are now able to provide "real time" determinations of not only earthquake magnitude and location, but also the ground shaking across all of southern California. We are also able to monitor the aftershock sequence with far more precision and speed than ever before.
A second important new instrumental initiative in southern California (by the Southern California Earthquake Center, NASA, and the USGS) involves installation of stations to record data from Global Positioning Satellites. Data from "GPS" stations provide an ongoing view of the slow processes of crustal deformation. With GPS instruments, scientists can literally track the slow, steady motion of the earth's tectonic plates. GPS data may also ultimately shed new light on earthquake processes because it will provide a more long-term, complete view of crustal and fault motions than can be derived from earthquakes, which are essentially simple snapshots in time.
These recent instrumental initiatives within the earth sciences have come of age at a fortuitous point in time, in parallel with the dawning of the Information Age. Both Trinet and the new GPS network are very much integrated with, and dependent on, the Internet. We are therefore not only collecting more and better data than ever before, but also able to disseminate it--to scientists, policy makers, and the public--much faster than ever before.
Compared to the situation just seven years ago (the time of the M7.3 Landers earthquake of 6/28/1992), the quantity and quality of information making its way to the public is vastly improved. This is--it bears mention--tax dollars at work. Major instrumental earth science programs do not come cheap, and recent efforts have been supported by a diverse collection of federal and state government sources, sometimes in partnership with private industry. The initiatives in southern California are also, one should note, pilot projects that were made possible because the 1992 Landers and 1994 Northridge earthquakes so effectly highlighted seismic hazard as a real and present danger in this region. Yet earthquake hazard is, of course, by no means restricted to the southern California. If the next big earthquake strikes too soon in northern California or elsewhere, scientists there will have far fewer integrated scientific/cyber-tools at their disposal.
These are exciting times to be an earth scientist; the community is beginning to see scientific data the likes of which we couldn't have previously dreamt of. We are also genuinely excited about our ever-developing role in making data and information available to people outside the scientific community. And it seems we are developing our new tools just in time. Earthquakes aren't happening because a new millennium is nigh, but, much as we might wish otherwise, they won't stop happening, either.