A current heat wave in western Asia can be compared with the one that just happened in the Pacific Northwest. The territory I have in mind appears on this map as a distinct feature just east of the Caspian Sea, where maximum temperatures up to 48C (115 F) are being indicated at a latitude on line with that of Oregon plus northern California. Similar heating farther south is mostly attributed to more desert-like conditions where temperatures at this level are closer to normal:
The next map has the actual anomalies for this entire region, in this case reported as daily averages, not maximums. The selected area is mostly showing +5-8C, which is very similar to those we saw in the Pacific Northwest at a high point on June 28 (see CL#1967). This gives us an opportunity to check out some of the details comparing how these high temperatures were created under the concepts stated in Carl’s theory. This latest one is especially interesting because there is a large area immediately north of the high anomaly area that has a cool type of anomaly along with extensive cloud cover and a patch of rain, which will be good for a followup review:
Let’s go directly to the cloud and rain map to gain a perspective of the full setup. The clear sky to the south is similar to conditions that prevailed in the Pac NW over the bulk of its heat wave. Referring to the previous map, note how abruptly the anomaly changed from warm to cool, with net differences ranging from about 7C up to a total of maybe 15C including the rainy area, as soon as cloud cover took effect:
This is a great piece of information, because it gives us an exceptionally clear marker that can be applied to calculations aimed at estimating the strength of cloud top albedo reflection under current seasonal conditions. To make this work properly we need to know what current precipitable water (PW) values look like across the region, so that map comes next:
Given that we don’t know what the PW historical average for the region is for this day, in this case we can simply set any estimate of that number aside. What we do know is that current PW readings around 30kg are undoubtedly on the relatively high side, as expected, and show a relatively consistent mixture across the entire area that includes clouds, no clouds, and clouds with rain. I interpret this to mean that the observed shift in temperature anomalies is practically all being caused by differences in cloud albedo and relatively little by variations in PW numbers. Will the great strength of these albedo numbers be maintained when solar factors in the NH are reduced in months to come? I have doubts, but plan to keep finding good examples of quality evidence like this one.
This same heat wave also provides climate scientists with an opportunity to test the “heat dome” theory of explanation for high temperature extremes that has been gaining popularity (see CL# 1972 on July 5). High air pressure is said to have a role in shaping the structure of the dome, in compressing the dome’s contents, and in bringing trapped heat down to the surface. I have been looking for a source of diagrams or instrumental imagery that would give us a clear visual demonstration of how this works. The air pressure readings in Today’s Weather Maps include an area of high pressure in far western Asia that does not line up well enough to be helpful for this purpose, but will keep looking for other things:
Carl