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INTERVIEW WITH DENNIS M. BUSHNELL

Marketplace sustainability reporter Sam Eaton invited Dennis M. Bushnell, chief scientist at NASA's Langley Research Center, to respond to Carl Hodges' vision for a Plan B, as Sam reported in "Seeing opportunity in rising oceans." [See Related link.] Here are excerpts from their interview.

SAM EATON: Carl Hodges lays out a plan to stop sea-level rise by expanding seawater agriculture on a massive scale and using drained coastal aquifers as giant storage tanks to counter rising seas. Will it work?

DENNIS M. BUSHNELL: Carl's Approach will "work." I know of no reason it would not. My only reservation is that if we seriously utilize Seawater Agriculture via salt plants [otherwise known as halophytes] on desert areas and aquaculture using saline/salt water to grow algae, we could greatly reduce the anthropogenic CO2 emissions by replacing petroleum, which would result in slowing the ocean rise. Other technologies such as drilled geothermal, direct solar such as solar thermal and PV and Biomass could be used to replace coal -- mitigating greatly ocean rise from electricity generation. That is, there would be little need to divert the ocean rise into coastal aquifers because there would be far less of a rise. Therefore, I would advocate using part of Carl's approach, seawater AG, initially to try and head off ocean rise. If that is not successful then the rest of Carl's approach could be utilized.

EATON: Does seawater agriculture have a place at the table when it comes to adaptation strategies for living in a warmer world?

Bushnell: Seawater AG and Saline/seawater agriculture/algae are an important part of an approach to try and head off warming as opposed to "living in a warmer world." Peak Oil was evidently in '06. With the tremendous Asian demand oil prices are expected to rise rapidly. Therefore, both from an economic AND a climate perspective we need to, SOON, replace Petroleum for transportation. The only viable candidates are hydrogen and biofuels. Hydrogen has major storage and infrastructure issues. Therefore biofuels appear to be the approach of choice going forward. Replacing oil will require tremendous capacity, which is only available for Biomass if we utilize seawater AG and Aquaculture/Algae.

EATON: What strategies would you propose for both preventing and adapting to global warming?

Bushnell: In my opinion, there are three levels of "solutions" for climate/warming. The first is green energy such as we have been discussing, along with conservation. If this is not successful, we will be forced to go to plan "B," which involves "mega-Engineering" such as sunshades in space, triggering volcanoes, altering the albedo via nano-particulates etc. There are many proffered solution approaches of this genre. All of these could involve major potential "unintended consequences" and would only be undertaken after serious computational modeling, much thought/consideration and a lot of finger-crossing. Plan C, if the first two do not work, is to re-engineer the Biota. The ongoing Bio revolution, including Genomics and Synthetic Biology, proffers the possibility of altering the flora, fauna and the humanoids to "take the heart," or to thrive in whatever conditions may occur/develop. We are currently studying the biology of what are termed "Extremeophiles," life forms that thrive in the most extreme conditions on the planet. These studies should inform and perhaps enable this "Plan C."

Eaton: Is "Plan B" enough?

Bushnell: As indicated in the last response, it may not be enough, or, more likely, it would go awry and make a bad situation much worse. Just to be clear about what climate changes we are faced with, the current projections are proving to be very conservative. The ice is melting much faster than predicted as an example. If the many positive "feedback loops" are included, then things change much faster and conditions become far worse. I suggest the audience might be interested in a recent book entitled "Under a Green Sky," published by Smithsonian books. It relates the current situation to the several previous warming events in geological history and indicates what is probably in store. It is not at all pretty. The author makes the point that the current anthropogenic CO2 changes are some 100 times faster than during even the most rapid of the previous extinctions, several of which were triggered by emissions from volcanic activity. The current anthropogenic utilization of fossil carbon fuels is substituting for the volcanic activity in terms of triggering the many positive feedback mechanisms. The result is global warming that gets pushed into hyper drive.