–by Mark Shields
I think we may need more choices than cause = CO2, cause = natural variability, and cause = unclear, for those who think there is warming; I don’t feel these options exhaust the interesting set of “causes”. I personally think, whether at any given moment the temperature trend is up or down, that the absolute level is higher than it would have been without mankind liberating large amounts of stored (chemical and nuclear) energy via Fossil Fuel, Fission and Fusion (FFFF). This concern is completely different than the concern about CO2 levels, and I think is an easier way to frame the pertinent question about what we should be doing about our use of energy.
These “FFFF” energy sources borrow from ancient reserves of potential energy and release this energy in the present timeframe at much higher rates than would have been the case otherwise (without human participation in the cycle). In contrast, rapidly cycled solar energy flux captured in the form of wind, solar, hydro-electric power (and even wood heating), is solar energy temporarily forced to do human directed work before being largely transformed back into heat within timeframes comparable to those in which mother nature would have done the same.
While I don’t pretend to understand the geological trends in earth temp cycles well enough to know if we are in a substantial warming cycle or not (relative to what?), I can see MANY glaciers are retreating and polar ice is receding in absolute measures in human life scale terms.
I can’t say this very visible level of warming momentum doesn’t happen every so often, and can’t even say for certain whether there is net warming or cooling going on in 2008, but I am very willing to wager that the increased FFFF energy being liberated in the past 300 years and past 30 years and next 10 years is:
· nearly all attributable to man,
· can be quantified/estimated,
· makes the earth warmer than it would have been without it,
· is increasing, and
· the rate of increase is non-sustainable.
Regardless of whether there is a tipping point in the stored carbon cycle, or atmospheric CO2, or the cloud cover, or solar cycles, or orbital mechanics cycles that singly or in combination can lead to large changes in climate in short time frames, there are things we know we are doing wrong that we need to slow and finally nearly stop.
Jared Diamond recounts numerous instances of substantial ecologic and climatic change in recorded history, and I think that current ecological changes in the biosphere are WAY out of control (i.e., non-sustainable).
It seems there are a number of things that could cause humankind to involute prior to us all cooking or freezing (“Some say the world will end in fire, some say in ice…” R. Frost poem I liked many years ago). Fighting over available energy in the face of uncontrolled demand for energy seems like an outstanding candidate for “ending in fire”. Militaries worldwide are definitely warming up.
So I would like us to learn to live within our means (i.e. within the solar flux energy budget), because I want Shune and Jimmy to have the opportunities I have had to live a full life, to learn neat things and to love good people. I think we need to curb our FFFF use not because the source of this energy is particularly finite (fusion may not be), nor because using it causes deadly carbon or radioactive by product changes in viability of the planet (fusion might not, depending), but because nearly all the excess energy tapped from ANY FFFF source is added to the reradiation burden of the planet, thus warming it.
Earth ‘floats’ suspended in a very high efficiency transparent thermos bottle, with a very bright light shining in one side, heating it up, and prior to man, there was an equal amount of reflected and re-radiated infrared energy leaving earth and these two were in a cyclic balance. Once mankind started liberating FFFF energies, over and above the Sun’s earthward energy flux (and steady tidal and geothermal fluxes), the earth mean temp went up sufficiently to result in a higher rate of infrared radiation so that the balance was maintained. I think there are people who can calculate how much warmer earth’s surface needs to be to radiate the total annual FFFF world expenditure. I’d be very interested in that estimate.
In the absence of some fortuitous natural heat dumping mechanisms (not yet proposed to my knowledge), what happens when one uses more FFFF energy is immediate: the earth gets warmer than it would have been and this excess warmth results in higher radiation of this heat into space until a new equilibrium is reached. When this delta in temperature happens to be at a point in a temperature cycle where marginal heating results in further loss of polar ice (which has a 90% reflectance as I recall from our days of building solar houses in Michigan), one might readily postulate that the human attributable temperature change of earth’s surface will exceed the calculated amount from FFFF use.
I’d like to check a button labeled: There is some global warming but the extent is unclear, and some of its causes are unclear, but one of the important non-sustainable causes is the ever increasing use of energy from FFFF sources.
Mark Shields, MD, MPH, MS, is a medical epidemiologist working for CDC as Chief of Strategic Information in Lusaka, Zambia (Africa) where he has lived with his family since 2000.