Oyster Fest 
Gary Cartwright
That Sinking Feeling
While government geologists argue over subsidence and sediment loading, the rest of us are wondering: Is the Gulf Coast toast?
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The quarrel between Dokka and Morton has been roiling for some time, and the NOAA’s National Geodetic Survey, which sets the standards for benchmarks and is the final authority on geodetic measurements in the country, appears caught in the crossfire. “A lot of geologists don’t understand what we do,” said Dave Zilkoski, the NGS’s deputy director. “The report is the best available information on subsidence rates we have. How they are interpreted is something else. Let the geologists work it out.” In a paper released after our conversation, Morton wrote that the rapid subsidence in Louisiana was largely the result of oil and gas production and that there was no evidence that the subsidence that had occurred in the past few thousand years was a result of natural processes like sediment loading and gravity gliding. “The historical rates of subsidence reported by the NGS do not apply to the recent geological past. Therefore, projecting them a century or more into the future without qualification is simply bad science,” Morton concluded. A Dokka colleague replied to Morton’s paper by noting: “The Gulf Basin has been subsiding for one hundred sixty million years. Why would it stop now?” Another Dokka defender said simply, “Morton is pissed because the numbers don’t fit with his preconceived notion. His expertise is in coastal and watershed studies, not in subsurface geology. He’s way out of his league.”
All sides agree on at least one thing: The benchmarks in both states are flawed and outdated. U.S. senator Kay Bailey Hutchison recently pushed for a $665,000 federal grant so that geologists at Texas A&M—Corpus Christi can update the height of Texas benchmarks. This process will require land surveyors to take elevations from somewhere outside the subsidence zone—probably in La Grange or Smithville—and work their way to the coast, at a cost of about $1,000 a mile. Until this happens, debates about sea levels and subsidence rates are strictly hypothetical. The NGS believes that the network it helped build for Harris-Galveston is working well and plans to develop a similar one for Louisiana, which, as the current hurricane season has demonstrated, needs it desperately. When I called Dokka in early July, Hurricane Dennis was roaring toward the Gulf Coast. He had just come from a four-hour meeting with evacuation officials in which he’d tried to convince them that the elevations on some of the evacuation routes were a foot lower than their maps showed. “Our rates are correct, and people need to heed them,” he told me. “People could be killed in a hurricane if they don’t believe elevations have changed.”
Scientific talk makes my head spin, but I saw with my own eyes a glaring example of subsidence in a part of Houston where no groundwater, oil, or gas had been extracted. Art Berman drove me to an area just north of Houston’s Katy Freeway between Gessner and Bingle, where Long Point Fault snakes under the subsurface and occasionally bulges up under the pavement. The fault, which is millions of years old, runs about twenty miles, east to west, and plunges to a depth of perhaps 20,000 feet, yet most residents of this area had no idea it was there until it began to wreck their streets, driveways, and foundations some years ago. In the 1300 block of Moorhead Street, we stopped to inspect a two- to three-foot-high ridge that had broken apart the sidewalk on the east side of the street and plowed up the driveway of a one-story ranch-style home on the west side. “This is what we call a growth fault,” Berman explained. “It will continue to grow as the weight of the sediment loads pulls down on its active side.” Though the Texas coastal plain is one of the flattest places on earth, we spotted “bump” and “dip” signs on most north-south streets from Hedwig Village to Spring Branch, along with cracking driveways, broken sidewalks, and curbs that seemed to be melting into the asphalt. “This is a unique, dynamic basin,” Berman told me. “We have to drill twenty thousand feet to reach a reservoir that everyone agrees was deposited at sea level. So how did it drop twenty thousand feet in a few million years?”
Combating forces of nature is a futile exercise, as is predicting what will happen a century from now, but that doesn’t mean we shouldn’t get real about what’s happening today. Everyone except the fossil-fuel industry and some elements of the Republican party knows that global warming is fact, not theory. In the twentieth century, the earth warmed faster than it has in any period in the past 10,000 years. Nearly every year since 1990 has been hotter than the year before. The Environmental Protection Agency estimates that the earth’s temperature will jump 3 to 9 degrees by 2100 (if that sounds insignificant, consider that during the last ice age, the earth’s average temperature was only 5 degrees cooler than today). Glaciers all over the world are melting. By some estimates, sea level will rise three feet by 2100, threatening not just barrier islands like Galveston but entire nations.
Like subsidence, climate change is a natural process, and scientists are divided over how much of it is influenced by human activity. But nearly everyone agrees that the buildup of carbon dioxide and other greenhouse gases traps heat close to the earth’s surface. It’s been more than 400,000 years since this much carbon dioxide was in the atmosphere. The United States is the only major country that thumbs its nose at the Kyoto accords, which attempt to control carbon emissions. The president insisted as recently as early July that Kyoto would “wreck the U.S. economy,” but his administration hasn’t offered a substitute or even acknowledged that there’s a problem. Quite the contrary: According to the New York Times, the chief of staff for the White House Council on Environmental Quality edited government climate reports to play down links between emissions and global warming.
Misdirection plays might win elections, but refusing to admit that the climate is changing doesn’t mean it’s not changing. Cynicism won’t carry the day in geological time, and it won’t keep Galveston from a watery grave or even give residents of Houston much comfort when they can see the Gulf from their kitchen windows.
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