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More than a few people in my meager sphere of coworkers, family, and acquaintances are of a decidedly conservative bent and apparently bathe in the fetid wellspring of the Fox network for their daily ablutions. I recognize this because more than a few use substantially the same phraseology as they express the similar contentions on politics or of some duplicitous liberal miscreant. Most are admitted non-sciency folk and have heard that the current dust-up about AGW, Anthropogenic Global Warming, derives from assertions of a self-serving conspiracy by unscrupulous scientists angling for grants or in service of some deeper, darker purpose.

Like many people I’m trying to follow and comprehend the topic of climate change and AGW. Having taken no more than an undergraduate semester of meteorology and oceanography as well as flight training, I can grasp basic concepts and use some of the vocabulary in a sentence. So, when I’m asked for my opinion I usually just shrug my shoulders and offer a scenario for consideration.

Forget CO2 for a minute. What happens to surface water if the atmosphere and oceans get a bit warmer? It’s safe to say that, generally, there will be more moisture entering the air. It’s a fact that water vapor is a greenhouse gas. Water vapor absorbs infrared energy from the sun. Any influence that manages to cause the atmosphere to hold more water is an influence that will cause the atmosphere to capture more thermal energy and result in warming. Being more buoyant that dry air, moist air can convect to produce clouds.

The change from liquid water to gas is an endothermic process. Energy is absorbed to produce water vapor from surface water. During cloud formation, upwelling air naturally cools and condenses to aerosols and droplets. These may freeze to ice and liberate the latent heat of fusion. This is an exothermic process, liberating latent heat which warms the air causing further convection. So, a parcel of moist air convecting upwards will result in an inrushing of surface air which is drawn upwards to sustain a column of rising moist air. The early cloud building phase of a thunderstorm (cumulonimbus) is characterized by strong updrafts from convection.

So, one might expect storm behavior to change as the relative humidity increases. As the average air temperature rises, the higher latitudes (north and south) might be expected to see some change as well.

In the northern hemisphere one of those changes could be the melting of higher latitude snowpack and glacial ice. Ice and snow pack consists of fresh water. Fresh water is less dense than salty ocean water. As fresh surface water runs onto briny oceanic water, it will tend to stratify according to density with lower density, less briny water tending towards the surface.

The thermohaline circulation, also referred to the Atlantic conveyor, is responsible for the gulf stream current that flows in a northeasterly direction along the Atlantic coast of North America and into the north Atlantic. This current is responsible for delivery of relatively warm water to the north Atlantic. These warm waters are partially responsible for the temperate climate of the UK and northern Europe. One of the most important concepts of climate science is that one cannot separate the oceans from climate. Due to the considerable heat capacity and latent heats of water (relative to air), the oceans are a substantial reservoir of energy capacity in direct thermal contact with the atmosphere.

The gulf stream’s arrival to the cooler north Atlantic where the water increases its salinity and density due to low temperature and evaporation to form a region of sinking water that forms a subsurface current. This current circulates to the Pacific and Indian oceans and eventually back to the north Atlantic in a loop of circulating water. For the north Atlantic, this loop is at the surface and transfers heat back to the north Atlantic in the form of warm surface gulf current water.

The gulf stream submerges between the coast of Norway and Greenland. In doing so, warm water is transferred to the north Atlantic. Should Greenland undergo a sudden warming with subsequent release of melted fresh water, it would be expected that the process of sinking of briny surface water would be suppressed due to the presence of less dense surface melt water from Greenland. The effect would be to suppress the potential energy of descending cold briny water feeding the Atlantic conveyor as well as oxygen transport to the ocean depths. Upwelling water from the deep transports vital minerals to support the food chain. The loss of this upwelling will have a distinct affect on the fisheries.

If it transpires that the loss of heat transport to the north Atlantic results in a general cooling of that body of water to form ice, how is the overall heat balance of the earth affected? Could it trigger another ice age?

The point of this is to offer that a rise in air temperature can lead to consequences that are not intuitively obvious. Talking about global warming should not end with just “warming”. The ramp up to global warming is a disturbance that may have surprising results.

Our local ACS section meeting tonight featured two speakers with opposite views on anthropogenic global warming (AGW).  One was a senior scientist from CIRES and the other was a retired physics prof from UCONN. 

The physicist did what physics profs like to do which is to say, reduce the problem to constituent elements. To make a long story short, the physicist tried to demonstrate that CO2 levels are the result of warming, not the cause.  He applied Henry’s law and did a lot of handwaving and criticism of climate science and modeling as well as some old fashioned back of the envelope calculations. It was a rather good demonstration of the climate deniers art.

The CIRES guy’s talk was really quite comprehensive and tied in observations from a wide variety of types of experiments to support the notion that CO2 has rapidly ramped up coincident with the industrial revolution- say the last 200 years or so. What was most persuasive to me were the isotopic data showing the deficit of C13 in the recent CO2 buildup. This data suggests that the accumulated atmospheric CO2 levels are measurably tipped towards biomass or fossil fuel origin rather than of inorganic origin.

As near as I can tell, much of the audience of chemists seemed to incline towards the climate denier. A vocal few were certainly skeptical of the data in the sense that the limits of the instrumentation had to be accounted for. But this was the normal skepticism one sees chemists display everywhere. I’ve done it myself.

Obviously, I’m not a climate scientist and would never be confused with one. I’ve been on the fence about AGW until tonight. I think I’m tipping slightly towards AGW now based on the isotopic findings. 

What I saw tonight was more like the parable of the three blind men and the elephant. The AGW denying physicist and more than a few in the audience understood at least part of the data and concepts. And from the area of expertise they held, felt they had a unique perspective on the problem. I gathered this from the nature of the questions asked.  

This is emblematic of the situation and in a similar vein to creationist “science”.  Creationism has all kinds of problems as a model of reality.  But what I often observe in its adherents is a limited knowledge of the theory they are trying to defeat.  In fact, I would offer that creationists comprise a kind of scholarly archtype. Creationists have the answer already and spend their time collecting data in support of it. This is characteristic of people who read devotionally rather than analytically.

I think learned people can fall into a kind of intellectual cul-de-sac from which many never escape. A lot of AGW deniers spend their time trying to debunk the IPCC data rather than performing experiments to achieve greater clarity.  AGW deniers are certainly well represented with conservative affiliation.

I was accosted by a coworker the other day who was so disgusted by my liberal ways and neutral attitude towards AGW that he couldn’t be bothered to expend the energy to fully dress me down for it. It just wasn’t worth the effort, apparently. Thanks friend. Where are all of these liberals the conservatives keep bitching about? I’m not seeing them.

Snow already. The mountains got snow well down below timberline yesterday. More to come tomorrow. Happy day.

An excellent entry into interesting and high quality articles on the net can be found at Arts & Letters Daily. I found an interview of physicist Freeman Dyson. In the interview, the writer is trying to understand how someone of Dyson’s stature could be skeptical of anthropogenic global warming. Basically, Dyson is skeptical of the models used and is skeptical of the assumption that the pre-industrial climate is automatically a valid baseline climate. Dyson accepts that there may be more desirable climate scenarios and that climate change is not automatically bad.

What is lost in most of the public discussion is the history of climate over the past million or so years. The fossil and geological record does not support the assumption that the global climate is static. We’re presently 10 or 12 thousand years past the latest glaciation episode in a series of glaciation episodes. As I recall, the interglacial periods in North America have averaged something like 10-15 thousand years.

What happens to atmospheric CO2 levels as the temperature rises or falls? Does rising atmospheric CO2 lead to a temperature rise or is it a result of a temperature rise? I have not encountered an adequate explanation taking into account the temperature sensitivity of carbonate equilibrium.

CO2 is not an inert substance. It reacts strongly with water to form carbonate.  Obviously CO2 will get absorbed by the biosphere. Do the atmospheric models take the various carbon sinks into account? Perhaps a reader knows.

Water vapour is a potent greenhouse gas and is certainly more abundant than CO2. It must account for some aspect of atmospheric temperature change. Do cloud aerosols and sea spray absorb significant CO2? It’s kinda complex.

Sometimes it is best to simply shut up and link to a superior post. This is such a time. In a recent posting, one writer, Harold Ambler, comes out against Al Gore in the global warming debate. While I am skeptical about his assertions on the effect of the solar flux on the earths geomagnetic dynamo, I think Ambler otherwise brings together quite a few good points I have seen elsewhere.

The ticket to my seat on the carbon bandwagon will soon post on Ebay.

WAWAwawa ..wawa..wawawa..waawaa..waaawaaa..wa..wa……wa……….wa.

The thermometer read -20 F this morning. It hasn’t been that cold for a few years.  As I sat in the Jeep listening to my battery die hard, my mind wandered fondly to the green meadows of P-Chem and the Nernst equation. This equation sets forth the relationship between temperature and cell potential.  The University of Arizona has this fantastic Nernst simulator (web version) that lets you dial in temperature and immediately see the effect on the voltage of the electrochemical cell.  It is plain to see that as the temperature drops, the EMF drops as well.

Knowing that nature wouldn’t let me summon sufficient wattage from my battery, I went back inside and switched on CNN.  After seeing multiple replays of an indignant journalist hurling a pair of shoes at our president, I was treated to an ad by the Central Intelligence Agency- the CIA. Yeah, the CIA is advertising on CNN!  Take a minute to get your arms around that.

Strangely, uncharacteristically perhaps, I experienced a synergistic swelling of sympathy after seeing the shots of Bush II being assaulted by Iraqi footwear followed by the patriotic CIA ad. For a moment- just a sparkle in time- a quorum of voices in my head agreed that somebody should kick that journalist’s ass. Bush II may be a buffoon, but he is OUR buffoon and nobody should treat him like that. There- I said it.

There is an interesting debate happening in the weather and climate modeling wing of the blogosphere. Seems that over at Wattsupwiththat someone has pointed out the significant part water vapor may play as an absorber of solar energy. All you have to do is look at the absorbance spectrum of water vs CO2 and you’ll see that the game is suddenly more complex than the incessant drum beating about CO2 would suggest.

There are a number of good websites on weather and climate out there. Rabett Run seems well centered in terms of the science.  If you are interested in the level of play happening in the real, behind the scenes debate, check out the references to Kirchoff’s law.  Physical meteorology is at the center of the whole debate. Assumptions about the applicability of certain laws, assumptions about the value of key variables, and other details of equation building can drive the nature of the conclusions. Planetary atmospheres are really quite complex!

I think it will be several more solar cycles before the right modeling assumptions shake out.


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