If a relatively small amount of precipitable water (PW) traverses over the Arctic Ocean at this time of year, what damage can it do? That’s my subject for today. By using the Weather Maps we can come up with some numbers that are useful. The damage, if any, will be caused only by an increase in surface air temperatures. It won’t be enough to cause any of the sea ice to melt at this time, but the air and the ice will still be engaged in a heat exchange, resulting in a considerable cooling of the air and a modest warming of the ice. That little bit of extra warming, on top of what the sun is producing at an increasing rate, if repeated over a number of days, will ultimately cause an amount of ice to melt completely away at an earlier than usual date. The “regular” mix of greenhouse gases, when their concentrations are increasing, with some PW included, do this same thing, but at only a slow pace and over a long time. When an extra amount of PW gets involved, making a sort of surprise appearance at a high altitude, the process can be quickly amplified. The full amount of amplification won’t be known until later in the summer, but we can still check out the early stages of its startup period.
We’ll start with the PW map. The principle we are going to apply, a basic component of my complete hypothesis, is that any doubling of the total amount (by weight) of PW in the atmosphere over head has the immediate effect of adding about 10C to surface air temperatures, entirely attributed to temporal greenhouse energy inputs. We have access to practically all of the numbers we need to validate the computation on any given day except for one, which is the historical average of PW value for the day. That has to be estimated, which we can do with reasonable confidence of getting a good answer. When studying most of these maps, be ready to magnify the images on your computer by around 300% in order to take away the best numbers from the tight scaling.
The focus today in on the light gray stream seen heading north in the upper center of image. The stream makes a curl to the right jut before it reaches the North Pole cross-hairs on the map. I get a reading of 6 to 7kg for the weight values of most of the “head part” of this stream. Nearby, at about the same short distance from the pole, values have fallen all the way down to as low as 1kg or an unresolved fraction thereof. The relative difference of about 7x thus represents nearly three consecutive doubles from one area to the other. Assuming that much of this entire central polar region will have about the same historical average PW value at this time of year, which I believe is a fair supposition, we can be looking for close-by temperature differences of around 25C or more across this region today and also anomaly differences in the same range. First, the temperature map:
One spot within the observed warm outline of where the head of the PW stream curls over shows a temperature of only about -5C. The pole itself sits at -30C, and places all around it are either warmer or colder by a pretty wide range of degrees. (You’ll need to magnify.) I think It all checks out quite well by spot locations, so let’s move on to the anomaly map:
The small area of bright red represents an anomaly of +18 to 21C. The blue area surrounding the pole is mostly made up of anomalies between -3 and -6C. It’s all in proper correspondence with temperatures. There is one more map to show today, because it holds a clear image of the very light jetstream wind that must be responsible for carrying the PW stream toward the pole as depicted on the first map:
Note how this jet started bending toward the right before reaching the pole, then widened and basically disintegrated, with pieces continuing over an array of different directions. This is how such a wide total expanse of warm anomaly can be created. Its relative high temperatures, caused by such a small modicum of PW material, attests to the power of leverage when the density of effective H2O molecules is at such a minimal level. This little PW concentration, given the opportunity to make deep penetration, was able to produce results that are indeed spectacular. From this day forward the frequency of repetition will be a matter of real importance, based in large part on rapidly evolving changes within the sequence of preceding events as described in other recent letters.
Carl