University of Colorado, Boulder
Global Death and Construction: Earthquakes on an Urban Planet
For much of the history of civilization, earthquakes have shaken rural communities – villages and towns, each with dozens to at most several hundred thousand people, amounting to fewer than 100 million people worldwide. Urban populations began to explode only early in the 20th century resulting in super-cities whose populations number in the millions. New construction methods were designed to house these new arrivals. In the next hundred years the population of planet Earth is expected to double, with 60% of Earth's 12 billion people living in supercities and megacities, the latter with populations exceeding 8 million. Tragically many of these new megacities lie on the world's tectonic plate boundaries, and have replaced villages known to have been destroyed repeatedly by violent earthquakes.
Our planet has consistently delivered no surprises: the relentless motion of the world's tectonic plates during the past 3 millennia are identical to those of the past 3 million years. Hence the distribution and frequency of past earthquakes are a fairly reliable indicator of future earthquakes. Studies of historical earthquakes combined with modern seismological estimates of their rupture parameters point to a grim seismic future for our new urban planet. With the exception of rare mid-continent earthquakes, we can forecast where most of the world's future earthquakes will occur, yet history tells us that we will not relocate our cities to avoid seismic damage. Clearly we must make buildings that resist collapse when they are shaken. The last two centuries provide guidance on how to construct buildings guaranteed to collapse under even modest shaking. The culprit is often faulty construction rather than faulty design. We are about to initiate urban society's largest housing project – a global "era of construction". The dwellings for our doubled future population are on the drawing board today. We have the engineering know-how to design buildings that don't kill people: we have the seismological knowledge that future earthquakes are unavoidable, and we have an enormous building program ahead. Prudence suggests that these three concepts be merged, yet more than half of the super-cities most vulnerable to seismic shaking lie in the world's poorest countries.
About Dr. Bilham
Education:
B.S., Cardiff University, Physics, 1966; Geology, 1967
Ph.D., Cambridge University, Geophysics, 1971
Honors:
Doherty Scientist, 1986
Guggenheim Fellowship, 2000-2001
American Geophysical Union Fellow, 2002
IRIS/SSA Distinguished Lecturer, 2002-2003
Positions held:
Professor of Geological Sciences, University of Colorado, 1986-
Associate Director CIRES, University of Colorado, 1996-
Chairman, Geophysics Program, 1996-2000
Director, NSF Absolute Gravity Facility, 1995-
Fellow, Joint Institute for Laboratory Astrophysics, 1985
Fellow, Cooperative Institute for Research in Environmental Sciences,
1986
Fellow, Royal Geographical Society, 1988-
Brief summary of recent research and activities:
My time is equally divided between experimental measurements of deformation of mountain ranges, volcanoes and earthquake regions (GPS, absolute-gravity, creep meters and tiltmeters) in Asia, California, New Zealand, Venezuela and Mexico, and theoretical studies of deformation mechanisms causal to plate-boundary and intraplate earthquakes. Popular magazine articles about my work:
Discover Magazine: The coming Himalayan Catastrophe, July 1995. Earth magazine: The measure of a Mountain, Feb 1996.
Economist: Earthquake's in India Worse to come 1 Feb 2001.
Movies:
ABC - The Terrible Truth about Earthquakes.
NOVA - Taller than Everest.
IMAX – Everest.
IMAX - Kilimanjaro: Roof of Africa.
Books:
I am currently writing two books: a book on urban earthquakes, and a book on Mt. Everest. The Everest book is linked to my work in deriving a new height for the mountain and discusses the geology, geodesy and geophysics of the Himalaya.
Societies:
Seismological Society of America
American Geophysical Union
Geological Society of America
Royal Geographical Society
Some recent publications:
Bilham, R., K. Larson, J. Freymueller and Project Idylhim members, GPS measurements of present-day convergence across the Nepal Himalaya, Nature., 386, 61-64 1997.
Bilham, R., and V. K Gaur, Geodetic contributions to the study of seismotectonics in India, Current Science 79(9), 1259-1269, 2000.
Bilham, R., Millions at risk as big cities grow apace in earthquake zones, Nature, 401, 738, 1999
Bilham, R. and P. England, Plateau pop-up during the great 1897 Assam earthquake. Nature, 410, 806 - 809 (2001)
Bilham, R., V. K. Gaur and P. Molnar, Himalayan Seismic Hazard, Science, 293, 1442-4, 2001.
