Written by Wolf Berger
I have, for several years, lectured to Rotary Clubs and to interested colleagues in the Earth sciences on the ongoing global warming and how one might extract, from the geologic record of the deep sea, insights to deal with this problem.
There is much lively discussion about global warming, both in scientific circles and in public forums. Among scientists, questions are being discussed regarding technical issues, such as the importance of clouds in affecting climate change, and the likely rate at which sea level will rise in the next several decades, for example. To some of these discussions geologic experience and insight can contribute valuable information.
In the public forum, rather more basic questions are debated, such as whether there is indeed good evidence for global warming, and if so, whether it is caused by human activities, and how it is likely to develop in the future and with what consequences, and whether or not we should do something about it, and if so, what. And how much (economic) pain such “what” might cause, and whether it will be sufficiently effective to warrant the effort.
Regarding this second set of questions, and especially the ones that surround policy, geologists have no more (and no less) to contribute than other people trained in rational thinking.
Geologists are predisposed to think about resources and their relevance to the standard of living – they are trained to find Earth resources. There is, in this predisposition, basically a positive attitude toward the use of resources. However, it seems unavoidable that the excessive use of resources has unintended troublesome consequences. For once, such use might help establish patterns of consumption that force the users into undesirable situations (such as becoming dependent on resources controlled by others). For another, such use might impact the environment in untoward ways.
Regarding the second issue, It now seems abundantly clear that the wholesale release of carbon dioxide and other trace gases is overwhelming the natural machinery of recycling, resulting in a pile-up of man-made gases that change the heat balance of the planet. The machinery of recycling, of course, is but a part of the entire climate system, which includes ice and ocean and atmosphere, and the carbon cycle, and the nutrient cycles.
There is no longer any doubt among those studying the matter (as opposed to some highly vocal folks who have heard about it on TV or read about it in trade books) that global warming is real and can be measured, and that it is unprecedented for the last million years in the rate of change it represents. As it is still modest relative to natural fluctuations, our insights into the working climate machinery are still sufficient to make correct assessments through calculation, such as the observation that maximum warming takes place in high northern latitudes, for example.
There is still much ice in such latitudes 
(enough ice on Greenland, for example, to raise sea level by 6 m after melting). Ice melts during warm summers – this is the fundamental mechanism invoked for explaining ice age fluctuations. Sea level will continue to rise, and the geologic record suggests that the rise could much exceed what is currently assumed in published authoritative assessments. When ice melts and raises sea level, additional ice becomes unstable when grounded below sea level (ice floats). Thus, there is an inbuilt positive feedback mechanism (a runaway effect) within the ice-melting business. At the last major melting period (between 10,000 and 15,000 years ago), ice masses collapsed for centuries and millennia, forced by relatively modest summer warming. Pulsed rises of around 1 inch per year (and perhaps more) were not uncommon during certain of these centuries.
When ice melts, it delivers freshwater on top of the saltwater of the sea. This establishes a tendency for greatly increased stratification: freshwater is lighter than saltwater. In other words, there is the possibility of building a lid on top of the sea. The implication is a great decrease in exchange of the atmosphere with the bulk of the deep ocean, which would mean reduction of carbon dioxide uptake by the ocean. In addition, a lid (already favored by strong warming) cuts down on the supply of nutrients from deep waters to the sunlit surface waters – the algae there starve, to the detriment of the entire food chain (which depends on the algae living in surface waters).
Regarding the present stance among governments to talk about the issue but do as little as possible, it is well to remember that once global warming has serious effects on the economies of the nations, it will be difficult to do anything but adapt to the changes. Besides, once the machinery of change is locked into positive feedback, the ensuing runaway will likely make efforts to cope with the basics rather ineffective. It is not clear that much time is left to deal with the issue.
To view a presentation on the subject click here:
…. for a general presentation at the Rotary Club level (compiled from a great number of talks over a time span of about four years)
…..for a more technical presentation to colleagues (given in Vienna, 2011, at the annual meeting of the European Geophysical Union).
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1944: Camano Class Light Cargo Ship was laid down for the US Army as FS-289 at Wheeler Shipbuilding in Whitestone, NY.
1945: Delivered to US Army.
1950: Acquired by the US Navy on July 1, 1950 and placed in service as USNS New Bedford (T-AKL-17).
1954: The movie, Mister Roberts, was made on the USNS New Bedford (T-AKL-17).
1955 - 1963: Used as a cargo supply ship for the Texas Towers, a network of advanced radar stations located off the Eastern Seaboard. In 1957, Capt. Sixto Mangual was commander of the AKL-17 and in 1961 it was rechristened the USNS New Bedford. The New Bedford, sailing out of State Pier, was keeping vigil when Texas Tower No. 4 callapsed off the New Jersey coast during a January 1961 nor'easter.
1963: Reclassified as Miscellaneous Unclassified (IX-308).
1971: The New Bedford (IX-308) served as a Torpedo Test Firing Vessel in the Puget Sound area.
1994: Ceremony in New Bedford.
1995: The ship was struck from the Naval Register on April 4.
2004: The Sea Bird's current disposition is a tuna long liner (fishing boat) out of San Diego, CA.
2006: Design of the Tesla Turbine began on June 11, 2006. The Sea Bird was sold by Defense Reutilization and Marketing Service for commercial service.
2007: The Sea Bird was drydocked for renovations.
2008: The Sea Bird setting sail to Sea-Tac in Seattle, WA.
2009 - 2010: The Sea Bird is currently docked at Seattle Sea-Tac.
