My post about sea level rise in the Adjustocene reminded me of an article from 4 years ago…
Five Ways Climate Change Threatens Energy in Texas
JULY 18, 2013 | 9:05 AM
BY MICHAEL MARKS
The Department of Energy released a report recently looking at how climate change and extreme weather could make our power supplies more vulnerable. Given that it’s the nation’s leader in energy production, Texas was prominently featured.
The report looks at both current and future threats to the energy sector from climate change. There are three major trends, it says:
- Air and water temperatures are increasing
- Water availability is decreasing in certain regions
- Storms, instances of flooding, and sea levels are increasing in frequency and intensity
I meant to write a post ridiculing this back then, but got distracted with other things in need of ridicule and never got back to it until now.
First: The low-hanging fruit appetizer
“Storms, instances of flooding, and sea levels are increasing in frequency and intensity.”
While one could debate whether or not storms and instances of flooding are increasing in frequency and intensity…
Sea levels are definitely not increasing in frequency and intensity.
Note: I said that the notion of increased frequency and intensity of storms and instances flooding could be debated. I didn’t say I agreed that they were.
Next: The main course
4. Goodbye to Galveston?
In 1969, Glen Campbell wrote the song “Galveston,” which trumpeted the Gulf Coast city as an idyllic seaside escape. While that may still be the case, one of the report’s projections says it may not be for long.
The report says that sea levels in Galveston could rise by as much as 3.5 feet by the end of the century. According to Climate Central, nearly 25% of Galveston’s population currently lives just four feet above sea level. Such a rise could also alter coastal ecosystems and damage infrastructure for energy and trade.
NOAA tracks two tide gauges on Galveston Island: Pier 21 and the Pleasure Pier (no, it’s not a house of ill repute – that’s in La Grange).
6.5 mm/yr times 87 years (2013-2100) equals 565.5 mm… about 1.855 ft… 1 foot and 10 and 1/4 inches… About half of the DOE’s Goretastic claim of 3.5 ft.
But… That’s just half-the-fun! Knowing just a little bit about the area, I went to the Harris-Galveston Subsidence District to see what effect groundwater withdrawal may be playing in the rate of sea level rise on Galveston Island. Much to my pleasure, I found a contour map!
Approximately three quarters (74%) of the sea level rise on Galveston Island is due to subsidence from groundwater withdrawal. Here’s the subsidence map as an overlay on the NOAA tide gauge map:
Finally: Le pièce de résistance (AKA dessert)
5. $1 Trillion Worth of Risk for Gulf Drillers
As climate change progresses, so too will the risk for oil and gas companies who drill in the Gulf. The report cites a study by Entergy Corporation and America’s Wetland Foundation that says that by 2030, over $1 trillion in energy assets in the Gulf of Mexico will be at risk from hurricanes and rising sea levels.
Well… That $1 trillion worth of assets have been at risk from hurricanes ever since we started putting assets in the Gulf of Mexico. Rigs, platforms and pipelines do get damaged and sometimes even destroyed by hurricanes. That’s the nature of hurricanes. (Hopefully, the operators of offshore wind farms realize this.)
Hurricane losses can also create opportunities and lead to innovation.
HELIX PRODUCER I
THE GULF OF MEXICO’S FIRST FLOATING PRODUCTION UNIT
The Helix Producer I DP2 monohull floating production unit is designed to produce hydrocarbons and export to shore via pipeline or tanker. The vessel is equipped with a disconnectable transfer system (DTS) which allows the ship to weathervane during production. This setup also allows disconnection from flowlines, pipelines and umbilicals, enabling the vessel to seek shelter from severe weather and during conditions where position onsite cannot safely be maintained.
Upon return to the production site, the DTS buoy can be retrieved and reconnected so that processing operations can resume.
The Helix Producer I is designed to serve smaller oil fields in deepwater over the life of the facility, and can also be used as an early production test vessel.
Process facility capacities are as follows:
Nominal Oil Production: 30,000 BOPD
Maximum Oil Production: 45,000 BOPD
Maximum Water Production: 50,000 BWPD
Maximum Total Liquids Production: 60,000 BFPD
Maximum Associated Gas Production: 72 MMSCFD
The HP-1 enabled the resurrection of a deepwater field after Hurricane Rita destroyed its production platform. Oddly enough, the field was named Typhoon. It’s now named Phoenix.
Even old fixed platforms can and have been modified to better handle hurricanes. This was done six years before the DOE and NPR warned us about hurricanes:
Existing platforms raised to increase storm clearance
A Devon Energy-operated platform with 44 people on board in the Eugene Island 330 field in the Gulf of Mexico was raised 4.25 m (14 ft) by 32 synchronously controlled hydraulic cylinders. The eight-leg platform, Eugene Island 330C, in 76 m (250 ft) of water originally was installed in the early 1970s. In 2005, Hurricane Rita passed through the field causing significant damage to EI 330C and claimed connecting platform EI 330S. In order to prevent repeated damage from future storms, EI 330C and neighboring platform EI 330B, which had also suffered significant damage from the hurricane, Devon teamed with Versabar to raise both platforms.
Due to the size of the hurricanes during the 2005 season and resulting uncertainty in future requalification metocean criteria, Devon Energy decided to have the platforms qualified to meet API RP 2A, Section 17, A-I criteria, even though the platforms were classified as A-2. Analysis showed that by raising the decks 4.25 m (14 ft), the effects of wave-in-deck loading would be removed and a comfortable air gap established. Analysis also showed that the additional leg movements attributable to increased platform leg length would not affect the structural integrity of the platform. The deck-raising was sanctioned by Devon and partners in May 2006, with raising operations for the two decks completed by November.
Regarding the nonsense about sea level rise. The EI 330 air gap restoration was due to seafloor subsidence, not sea level rise.
Offshore production platforms and drilling rigs are designed to operate in the oceans. Oceans have these things called “waves.” Waves are a lot bigger than sea level rise. And the industry has steadily improved the survivability of platforms over the past 50 years.
Fixed platforms are designed to have a minimum air gap above the crest of 100-yr waves. The estimated 100-yr waves and air gaps are very large relative to sea level rise.
Simply put… 1-2 ft. of sea level rise per century is irrelevant to a platform designed to last less than 50 years, deal with 10 ft. of seafloor subsidence and handle 75 ft. waves…
Deck height is the vertical distance from the still water surface to the underside of the lowest deck structural element on the platform. It is important to construct oil platform decks high enough above the water’s surface to avoid waves washing over the top, which could overload the platform and destroy it. While deck heights can be too low for several reasons, the two most common are:
Age — Older platform decks were set low because of available construction equipment at the time and because of a lack of knowledge of wave heights in the Gulf of Mexico and;
Subsidence — Some areas of the Gulf of Mexico floor have experience several feet of subsidence, or settling, related to production.
Usually, significant settling is found in older platforms because it can take 20 years to obtain 8 to 12 feet of subsidence. For example a platform installed in 250 feet of water 35 years ago may have been installed with a deck height of 45 feet. But after 20 years of production from multiple wells, there may be 10 feet of subsidence that reduces deck height to, say, 35 feet — leaving the platform more vulnerable to wave-in-deck loads never considered in the original design.
Whereas it would take a 75-foot wave height to reach the original deck when it was 45 feet above the still water surface, it would only require a 58-foot wave to reach the same point on the deck with 10 feet of subsidence. The chance of a 75-foot wave occurring at a platform site in the Gulf of Mexico in any given year is about 1 percent while the chance of a 58-foot wave is about 6 percent — placing the subsided platform at a significantly higher risk.
- Galveston Island is not likely to experience another 3.5 feet of sea level rise this century, it is not about to vanish under the Adjustocene Sea and three-quarters of its recent sea level rise is due to subsidence.
- $1 trillion worth of oil industry assets in the Gulf of Mexico are at risk to hurricanes and storms. Always have been, always will be. We knew that beforehand and continuously try to improve the survivability of things we build in the oceans.
- Rising sea levels are irrelevant… even in the Adjustocene.