The Rational Environmentalist    
[ February 5, 2007 by Jimmy Hogan ]

Does Particulate Reduction Help Explain Progressive Global Warming Trends?

Jimmy Hogan
February 5, 2007

Recently a friend of mine, concerned about my well being (and the survival of the planet), asked me to take a serious look at global warming. I’m generally a skeptic of these Malthusian prophecies but since this one is gaining so much steam in the media and in the public consensus I thought I would check it out.

What I found were some very interesting points and a very unexpected conclusion.

First of all, everyone seems to generally agree that:

  • It’s getting hotter and the increase in temperature is progressive; with the majority of the increase over the last century occurring in the last 30 years.
  • If this warming continues at the projected progressive rate or even linearly we’re in trouble (how much trouble is debated but trouble none the less).
  • CO2 concentrations in the atmosphere are going up.
  • The Greenhouse Effect of CO2 and other lesser Greenhouse gasses alone does not account for the temperature increases. Most greenhouse models suggest a chain reaction where a smaller warming due to the CO2 increase has pushed us over the tipping point causing increased concentration of water vapor in the atmosphere that results in the observed total greenhouse warming effect.
  • Though there is a large consensus on the matter there is still no proof of a cause and effect relationship between CO2 and the observed levels of heat gain attributed to the greenhouse effect.
  • The skeptics, though they have offered a great deal of science to contradict CO2 as a primary cause, have offered their own hypotheses but have yet to offer a better and proven explanation for the unprecedented progressive global temperature gains.

After cutting through mounds of hype and hysteria on both sides of the global warming argument these 6 are points that neither side can dispute. I’m sure there are zealots on both sides of the issue who will wish to debate nuances but for all practical purposes the list stands.

Now, given the above, where do we go from here? Well, I believe there is an area of the science that deserves a lot more attention than it is currently given. Global warming proponents say ‘Global Dimming’ has masked some of the heat gain we otherwise would have already experienced due to the greenhouse effect. The more I research this, however, the more I become convinced that this idea is not secondary but fundamental to observed warming trends.

Global Dimming generally says that airborne particulates cause droplets to form into clouds that reflect sunlight and radiant energy back into space. Environmental scientists suggest that man made particulates, as a result of industrialization, car exhaust, etc, have increased this effect and have shielded us from additional world warming from the greenhouse effect.

But what if the observed warming attributed to the greenhouse effect, instead of being masked by dimming, is actually a result of the reduction in particulates over the last century – primarily over the last 30 years?

This seems like a simple idea; but the more I research it the more evidence I find to support it. I first publicly posed the idea in the comments forum on on 01/22/2007 and in defending the idea I’ve found that the effect of particulate reduction on weather is well known. One such effect is measured in predictable cyclic weekly weather patterns called the Weekend Effect.

The weekend effect is when traffic and industrial output decline over the weekend a noticeable change in local weather can be observed. Scientist attribute this effect to airborne particulate reduction. If traffic and industrial particulate fluctuations over a weekend can make observable and predictable differences in the weather, could systematic reductions in particulates over the last century (primarily in the last 30 years) better explain warming attributed to the greenhouse effect?

Another interesting thing I discovered in this research was the China Paradox. China has increased their CO2 production substantially more than we’ve increased ours in the US over the past 2 decades but their temperature is declining. The difference is in our air quality standards; where China is about 50 years behind the modern industrial world.

Could it be that instead of CO2 this all comes down to 7th grade science? Humidity has increased and suspended water vapor in the atmosphere is the primary greenhouse gas. Without particulates to assist the water vapor formation into clouds/fog/smog, more primary radiant energy reaches the earth. Since more water vapor is suspended in the atmosphere more secondary reflected radiant energy is absorbed (greenhouse effect).

The implications are tremendous. If progressive particulate reduction helps explain the observed progressive global warming then what does that do to the trend lines? Certainly we are reaching a point of diminishing returns in fighting particulate pollution if currently our biggest problem with car and power plant exhaust in America is CO2… a natural by product of breathing that helps plant life.

If particulate reduction is a primary cause of the observed greenhouse effect then what we are seeing is an adjustment not a trend. The dire future predictions of man-made global climate warming are, at least partially, unfounded and our substantial investments to counteract these trends; made at great cost to other possibly more worthy causes; is folly.

I personally am just a layman in all of this and although I consider myself a pretty smart fellow I realize I am way out of my league when it comes to details of worldwide climate science. My solution does seem at least as plausible as the other Rube Goldburgesque CO2 progressive models though.

So I put the question to the ultimate arbiter… the world wide web community of pundits and prophets… the proverbial ‘Army of Davids’ as Glenn Reynolds puts it. Please tell me… does a little common sense and a paradigm shift in perspective have a place in the global warming debate?

Please let me know your thoughts.

copyright 2007 - Jimmy Hogan - all rights reserved