Subsidence Survey Would Aid in Climate Controversy
Having won control of the U.S. House of Representatives on November 6, House Minority Leader Rep. Nancy Pelosi (D-CA), as this column is being written, the presumed Speaker of the House, will ask the Democrat caucus to create a select committee on climate change similar to a former panel behind the failed effort to pass cap-and-trade legislation when her party last held a Congressional majority in 2009-2010.
Pelosi told The New York Times the committee would “prepare the way with evidence” for energy conservation and other climate change mitigation legislation.
So, what does this mean for surveyors?
As I wrote in POB in November 2007, Massachusetts v. Environmental Protection Agency, 549 U.S. 497 (2007), the case cited as justification for cap and trade and other climate change proposals, provides a peek into geospatial issues related to the environmental debate.
Writing the dissenting opinion for Justices on the losing 5-4 vote in the Supreme Court, Chief Justice Roberts wrote, “One declaration states that ‘a rise in sea level due to climate change is occurring on the coast of Massachusetts, in the metropolitan Boston area,’ but there is no elaboration. And the declarant goes on to identify a ‘significan[t]’ non-global-warming cause of Boston’s rising sea level: land subsidence [i.e., the sea is not rising; the land is sinking]. Thus, aside from a single conclusory statement, there is nothing in petitioners’ standing declarations and accompanying exhibits to support an inference of actual loss of Massachusetts coastal land from 20th century global sea level increases. It is pure conjecture.”
He went on to write, “The Court’s attempts to identify ‘imminent’ or ‘certainly impending’ loss of Massachusetts coastal land fares no better. One of petitioners’ declarants predicts global warming will cause sea level to rise by 20 to 70 centimeters by the year 2100. Another uses a computer modeling program to map the Commonwealth’s coastal land and its current elevation, and calculates that the high-end estimate of sea level rise would result in the loss of significant state-owned coastal land. But the computer modeling program has a conceded average error of about 30 centimeters and a maximum observed error of 70 centimeters. As an initial matter, if it is possible that the model underrepresents the elevation of coastal land to an extent equal to or in excess of the projected sea level rise, it is difficult to put much stock in the predicted loss of land. But even placing that problem to the side, accepting a century-long time horizon and a series of compounded estimates renders requirements of imminence and immediacy utterly toothless.”
The Chief Justice questioned what caused the alleged loss of land and pointed to a lack of evidence of sea level rise. In other words, the United States lacks geospatial data to measure, monitor, verify and validate the alleged consequences of changes in the climate.
Rise or Fall?
While considerable attention is paid to “sea level rise,” there is little discussion of coastal and inland subsidence. If the former is addressed without taking into account the latter, the problem will not be solved. USGS did a special local study in the Hampton Roads/Tidewater region of Virginia and concluded 50 percent of the change was subsidence. “Data indicate that land subsidence has been responsible for more than half the relative sea-level rise measured in the region.” (Land Subsidence and Relative Sea-Level Rise in the Southern Chesapeake Bay Region (2013)) and nationally, “an area of more than 15,000 square miles in 45 States experience land subsidence.” (Land Subsidence in the United States, (1999)).
Donn Dears, a retired General Electric executive and the author of several books on energy and the environment, including “Carbon Folly” and “Nothing to Fear: A Bright Future for Fossil Fuels” notes, “Subsidence is a major contributor to the apparent rise of sea levels along the East Coast, and has been ignored by the media when it has published articles about coastal flooding, including flooding in Miami.”
Dears cited data showing sea levels will continue to rise, as they have for the last several thousand years, at a rate of 8 to 10 inches per hundred years in Miami. But portions of Miami have subsided at the rate of 12 inches per hundred years, but since subsidence from the aquifer covered less time, it’s been estimated that subsidence has amounted to around 7 inches over the past 80 years.
He adds, “Sea levels will continue to rise at around 10 inches per century, while subsidence will continue as long as we draw water from the aquifers and the Earth continues to rebound from the last Ice Age.”
“Subsidence and its impact on leveled bench mark heights has long been a concern of the National Geodetic Survey,” says Rodger Phelps, PLS, PSM, former president and CEO of Vernon F. Meyer and Associates (later known as 3001). “We ran levels in Louisiana as a contractor for the Department of Energy in the 1970s and the National Geodetic Survey added our benchmarks to their national network. We did GIS or ‘multipurpose cadastre’ projects for NOAA in the 1980s and found significant evidence of coastal subsidence.”
The principal causes of subsidence, according to the USGS, “are aquifer-system compaction, drainage of organic soils, underground mining, hydrocompaction, natural compaction, sinkholes and thawing permafrost.” Another cause is tectonic subsidence, the sinking of the Earth’s crust on a large scale, relative to crustal-scale features or the geoid, prevalent in areas such as Texas, Louisiana, Mississippi and Alabama, along the coast of the Gulf of Mexico.
In recognition of the need for a national subsidence data acquisition program, the Joint Government Affairs Committee of the National Society of Professional Surveyors (NSPS) is establishing a subcommittee to explore the feasibility and desirability of legislation in Congress to authorize and fund such a program.
“As surveyors, we have a professional responsibility to educate Congress on this challenge and recommend a solution to serve the interests of our Nation,” says Patrick A. Smith, RPLS, vice president of Surveying And Mapping, LLC (SAM) in Austin, Texas, and chair of the NSPS committee. “Subsidence has a significant impact on economic growth and the environment in many parts of the United States. Bringing this to the attention of Congress will benefit the citizens by assuring a wise investment to identify and monitor the problem now, rather than waiting and wasting money to play catch-up later.”
Such a national or coastal program would require leadership and collaboration from several federal agencies, such as NOAA/NGS, USGS, the U.S. Army Corps of Engineers and FEMA. Additionally, it would also require close partnerships with state and local government, and contracts with numerous qualified surveying firms. The NSPS study will focus on the acquisition of high accuracy positioning data, including partnerships, roles and responsibilities, data standards and a funding strategy.