A response to points raised in comments

June 12, 12:45 AMOrlando Science Policy ExaminerSteven Andrew

This site had a banner day yesterday and both the Examiner and I greatly appreciate your interest! A number of readers graciously took the time to raise some salient points in comments below. I’d like to take a moment and address a couple of them, but first a few pointers. Not only do I tolerate dissenting comments, I strongly encourage them. Debate and discussion are the life blood of science and democracy alike. Well written, critical comments to my posts will not only be addressed as time allows, I may elevate them to the body of the post so that other readers can reflect on them.

A reader named Don correctly mentioned that conservative have no qualms with stem cell research, rather, they object to embryonic stem cell research because it requires the destruction of viable human embryos. This may come as some surprise, but the ultimate goal of stem cell research is to not use embryonic material, or adult donor cells for that matter. The Holy Grail of regenerative medicine is to learn how to coax the body’s existing adult stem cell population into repairing or regrowing damaged tissue and maybe, one day, entire organs! But to reach that ideal outcome, stem cells of all kinds, embryonic, infant, umbilical cord, marrow, adult, and even cancer stem cells have much to teach us.

Embryonic Stem Cell Lines are produced from fertilized embryos in an early stage of development consisting of about 60 to 100 cells called a blastocyst. I’m sensitive to those of you who feel this crosses an ethical boundary and would rather researchers worked with material that does not represent a potential, unique, human life. But restricting embryonic stem cell research won’t save a single one of those potential lives for one simple, inescapable reason.

Thousands upon thousands of healthy blastocysts are produced every year in IVF clinics for the benefit of people who can’t conceive children the old fashioned way, but who wish to experience the joy of parenting. Enough children have been brought into the world in this way to fill a city. But the vast majority of those frozen blastocysts are never used. Of those left over, a tiny fraction are adopted by selfless, courageous women willing to carry them to term as snowflake babies.

The thousands remaining have only two ultimate destinations: certain destruction in a medical incinerator, or life in a Petri dish used to find potential cures to virtually every disease and injury known to medicine. Preventing a handful of blastocysts, already marked for destruction, from being diverted for research won’t save a single one of them. In fact it absolutely guarantees they will perish forever. For those who wish to end the wholesale destruction of blastocysts, forget about ESR, you’ll have to ban IVF procedures. And any politician who wants to go up against a bunch of photogenic IVF kids will find themselves in the unemployment line the day after the election. 

Many respondents questioned the scientific consensus on human induced global climate change. Let’s be clear: If Sarah Palin and Al Gore were to duel it out over global warming, it wouldn’t make a wit of difference who won as far as the underlying science – although I’d put my money on the sharp-shooting lady from Alaska in a heartbeat! And there are always outliers who will disagree with any conjecture in science. I can give you the name of a Ph.D. in astronomy who preaches an earth centered solar system. Make the check big enough and I bet I can find a trauma surgeon who’ll swear under oath that decapitation isn’t fatal.

As far as the science, temperature and man-made greenhouses gases are empirical; they’re something we can directly measure. The fact is the NASA Global Temperature Record shows an unmistakable, sustained uptrend in average global temperatures over the last 150 years. Carbon and other heat trapping substances liberated from ancient fossil fuels have a chemical and radio-isotopic signature which allows them to be distinguished from other sources. The increase in those anthropogenic GHGs matches the NASA record like a glove, with one fascinating exception.

Note the downturn and starting around 1940 followed by a slow rise for the next two decades. This is thought to represents in part the cooling effect of sun blocking aerosols that arose during and after the industrial buildup and ensuing carnage of World War 2. Smoke and dust rain out, they have a half life measured in weeks and months, but greenhouse gases like methane, sulfur compounds, and CO2 that were released from factories on a 24/7 war footing and cities burning under the onslaught of bombs and battles linger for decades and centuries. The GHGs soon won out, and global temperatures resumed their upward climb. In addition, paleoclimate researcher Dr. Michael Mann of Penn State explained to me that much of that data was biased towards the northern hemisphere, and that after the war, when more data south of the equator became available, the effect, although still present, diminished.

Yesterday, I took the liberty of phoning Dr. Gavin Schmidt of the Goddard Institute for Space Studies to get some idea of how those complex models were calibrated and tested. He sent me images taken after the eruption of Mt Pinatubo in 1991 showing beautiful layers of dust and gas silhouetted by the setting sun. Models at the time predicted the layers of aerosols would produce short term global cooling for a period of 6 to 12 months, and that eventual GHGs released by the same eruption could incrementally raise temperatures over the next few years. This was a grand experiment for climate models and they passed with flying colors. Models used today are far more sophisticated and have been rigorously tested. Those and other models correctly predicted the record loss of Arctic Ice, more intense hurricanes, and rapid glacier melting, all of which are now well documented. Changes in the Greenland and West Antarctic Ice sheets are also behaving as predicted. There have been no observed changes in solar output, no recent spate of enormous volcanoes, and no newly discovered massive under sea geothermal events to account for the measured increase in greenhouse gases.

To recap: we have empirical data showing a gradual and accelerating increase in the earth’s average surface temperature, we have direct measurements of an increase GHGs, we know that at least a significant portion of those GHG come from human activity, we have models tried, true, and tested that determine cause and effect, and incidentally predict further change in the future, and there is at present no other phenomena that can explain it.

And yet, there's no reason to be alarmist: this isn’t a poor backwater nation, this is America! We kicked the Nazis out of Europe, put a man on the moon, and prevailed over the most dangerous, nuclear armed adversary the world has even known in the Cold War with good old fashioned American ingenuity, capitalism, and national resolve. Even if global warming were the hoax of the century, the other benefits, energy independence and national security, a cleaner environment for our children, an economic boom in new jobs, and best of all, depriving terrorist funding regimes of petro-dollars, are not exactly poor consolation prizes. And, if the science is correct -- and its looking more and more plausible everyday -- we still have some leeway, time to reduce greenhouse emissions, develop cleaner energy sources, and take steps to protect vulnerable, low laying coastal regions from rising sea levels.  But if we're going to ignore these problems, blame it on ideological differences, resort to insults, then our collective intelligence as a species barely surpasses the ancient mats of caramelized bacteria that got us into this dilemma in the first place. We might as well bury our heads in the nearest sandy beach and wait, while the ceaseless, rising waves and supercharged storms do their patient work.