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Monday, May 28, 2018

Climate change numbers


I try to explain climate arguments leaving out numbers.  But they are the lifeblood of any science so here are a few very interesting measures.  The #1 greenhouse gas isn’t CO2 but H2O vapor.  There is 540 times as much water vapor as CO2 (only .00039 of the atmosphere) in the atmosphere and it is 10 times as effective in greenhouse entrapment.  So why aren’t manmade global warming advocates screaming about irrigation and over-forestation? Methane is an even smaller trace element and accounts for less than 1% of greenhouse warming (water =90%, CO2= 3.5%).  Atmospheric composition is roughly 390 parts per million of CO2 up from 270ppm  in 1600AD before the industrial revolution.  Sometime around the year 2100 CO2 will reach double the pre-industrial revolution output.  (These are all numbers from the andogenitive global warming advocates.)  The global warming models are very complex concerning how air of various temperatures and pressures variously absorbs radiation of varying wavelengths.  So if we double CO2 the average computer model says the rate of reduction of Earth’s cooling will be about 3.7 watts per square meter. This compares to satellite measurements of  total lost to space power of 235-245 watts/ sq. m (inexact).  3.7 watts/sq. m. works out to global warming of about a degree Celsius. But atmospheric convection at high altitudes lowers this to about 0.5 degrees.  James Hansen of NASA, a manmade warming advocate also estimates that there are other factors lowering the 3.7W/m2 to about 0.8 W/m2.  That’s just a fraction of a degree, not nearly enough to create the 2 to 4.5 degree estimates of warming they are predicting.

            So how do the modelers get 2 to 4.5 degree temp increases? They propose that the warming amplifies itself. Some propose an almost runaway warming with even larger than 4.5 degree increases.  But no one knows for sure if a little warming leads to a lot.  It’s a problem of estimating the feedback. 

            One of these feedback effects involves glaciation.  If warming melts glaciers, but increases snowfall atop them, they actually will grow during a warm era. Negative feedback. (There has been a huge discussion of this and conclusion is that the expansion or contraction of glaciers, both occurring around the world, is unknown and probably not related to CO2.) Another folly was the hockey stick graph, which showed flat temps for the last 2000 years but then suddenly rising since 1900.  This counters all the old anecdotal evidence of Europe’s Little Ice Age and the Medieval Warming.  The hockey stick temperature graph was derived from tree ring data that tried to link tree growth with temperature in arid western N. America.  But we know that desert trees care far less about temp than water.  So it was a bad non-causal correlation.  The hockey stick graph is history. 

            Think of clouds.  If we get less clouds, it is reasoned, the sun beats down the earth warms.  But counter-intuitively this isn’t so.  Think of a cooling of the oceans.  The wind blows and cools the oceans like wind blowing across your wet skin.  But this increases the moisture in the atmosphere which makes clouds and rain, which in turn releases the heat into the atmosphere.  So the earth might seem to have a temp regulator in water vapor—cool the ocean and you get warmer atmosphere.  Warm the ocean and you get a cooler atmosphere.  There are other natural effects.  Some may produce positive feedback while oceans and clouds may produce negative feedback. 

            We know a bit about some big ones.  There is a prominent oscillation of current and wind patterns in the northern Pacific called the Pacific Decadal Oscillation, PDO.  The negative cycle produces much more cloud cover worldwide.  Sometimes warm air from the south invades Alaska, sometimes polar air.  And the PDO goes back and forth about every 30 years.  [other oscillations in the Atlantic with hundred year cycles]  The PDO brings different cloud cover and factoring this into a model, it almost perfectly fits the temperature data that suggest 0.7 degree increase since about 1900.  This is especially interesting since there was a big temperature run-up before 1940, then an abatement until the mid seventies.  If you accept standard global warming via CO2, you are forced to ask why was there so much temperature increase prior to 1940 when CO2 emissions were slight but just as they really kicked in about 1945, we got cooling for 30 years?  Recently, there has also been research that proves that increasing CO2 increases upper atmosphere clouds that deflect sunlight in the tropic regions.  This is a huge negative feedback that has the research camps now divided into the CO2 only models versus the scientists who argue that we can’t neglect natural forcings and feedbacks.

            Complicating all this is money.  The Intergovernmental Panel on Climate Change. IPCC, is a big benefactor of research money that has kept the CO2 modelers in vogue, while shutting out the natural effects folks.  This is a rare situation in science, akin to the scholastic school of medieval scholars who shut out Kepler and Galileo.  But ultimately science is about truth and not where government money goes.  We’ll just have to see where truth leads.