However, the federal government's General Accounting Office also recently issued a report on various proposals for geoengineering the Earth — to reduce carbon dioxide, adapt to climate change, and develop strategies for climate intervention — they reviewed current scientific research, and considered such technologies at the present time to be “immature.”

The GAO report cautioned that major uncertainties remain on the possible consequences, stating: “Climate engineering technologies do not now offer a viable response to climate change. Experts advocating research to develop and evaluate the technologies believe research might provide an insurance policy against worst case scenarios — but caution that the misuse could bring new risks.” See this abstract from the GAO report.

I don’t disagree with the GAO’s overall conclusion… No proposed geoengineering endeavor scored higher than three points out of a possible nine. Research must continue, but zealots should not be empowered when potential side effects are huge.

But one experiment that clearly should proceed on an intermediate scale is to create “white cities”… by whitening rooftops in a few warm climate metropolitan areas and see if the effects are positive. The data would be useful, and it’s an inexpensive measure with few conceivable downsides.

And yet, a majority of climate scientists agree that humans already are modifying earth’s climate. Jane Long, director of the Lawrence Livermore National Laboratory, stated that “We are doing it accidentally….Going forward in ignorance is not an option.”

My biggest complaint? There is one proposed geoengineering project that gets short-shrift in every single appraisal I have seen, and this GAO report is no different. It is the only method that would directly imitate a natural process that is already known to remove megatons of carbon from the air, every year. A natural process that has no negative side effects but dozens of positive ones — like helping to feed the world. That process is Ocean Fertilization.

Ocean fertilization involves adding micronutrients to the oceans to stimulate biological productivity, which removes carbon dioxide from the atmosphere, sequestering it as sediment in the deep ocean. This could also reverse a widespread decline in phytoplankton, the basis of oceanic food chains. Preliminary trials were highly localized, but indicated that the potential for iron-induced carbon sequestration may be lower than originally hoped – but this has not been systematically pursued.

And yet — can anyone explain to me why the only ocean fertilization experiments were crude, blunt dumping of powdered iron? How does that emulate nature?

Sure it’s a critical bottleneck nutrient. Still, I’ve seen other proposals, such as wave powered, one-way siphons to raise cool, nutrient rich bottom water above the thermocline. Or using wave power to drive bottom-stirrers, sending mud plumes rising — just like what happens off the great fisheries of Peru. (I described such processes in my novel, Earth, published in 1989). The energy profiles may or may not be efficient… we’ll see… but no one can argue that those two don’t emulate precisely the most healthy, wholesome, and natural way that the Earth already pulls down megatons of CO2.

Of course, we must beware of unintended consequences of such large scale engineering. Ken Caldera, a climate expert at Stanford University, cautions, “The real question is what are the unknown unknowns: Are you creating more risk than you are alleviating?” We need to be collecting the data that will allow us to make informed decisions.