On Sunday I wrote here how any warmth that gets found anywhere on the globe almost always gets blamed on heat supposedly getting trapped by rising atmospheric CO2 concentrations (due to man). Of course here all other powerful, real factors such as solar and oceanic cycles get ignored.
Yet in the case of Japan, we see that it's recent temperature increase happens to coincide with more solar radiation reaching the surface.
All of Germany's temperature rise came in just 2 years
And not surprisingly, the same turns out to be true for Central Europe – particularly Germany.
Germany's DWD national weather office has been keeping records since 1881, and what follows is a chart of Germany's mean annual temperature anomaly for the period:
Germany mean annual temperature anomaly since 1881. Data source: DWD here.
The question is: Why have temperatures gone up? Has this temperature rise, particularly since 1990, been due to CO2 trapping heat?
One interesting aspect from the above chart is that we see Germany temperature saw no increase from about 1900 to 1990, but then suddenly it shot up almost instantly by a full degree. In terms of warming, that's not how CO2 is supposed to work. CO2 doesn't sleep on the job for almost a century, then go to town in a single year or two.
Hot electronic thermometers?
For this sudden 1990 warming, one scientist blamed the temperature leap on the DWD changing their measurement stations over from mercury thermometers to electronic thermometers right about that time. A side-by-side comparison of the old mercury and new electronic system showed that the electronic instrumentation yielded results that were a whole 0.9°C higher!
That alone could already explain the entire difference happening at about 1990.
More sunshine across Germany
But perhaps there are other factors at play. For example maybe clouds are having an impact on Germany's mean annual temperatures. Let's look at the available data on sunshine from the DWD:
Germany mean annual sunshine anomaly in hours of sunshine. Data source: DWD here.
The sunshine anomaly chart above shows well above average amounts of sunshine over the past 28 years, and so it should be no surprise that the recent years in Germany have been averaging about 1°C warmer than normal.
Naturally a number of factors can have strong impacts on Europe's temperature, especially the direction of the prevailing winds and weather patterns.
Westerly winds from the Atlantic act to keep the continent mild during the winter, and cooler during the summer, but vice versa during the summer. It would be interesting to have data on wind direction – a topic for a future post.
Steep precipitation drop over the past 20 years
Another factor is precipitation, which would indicate more cloud cover and so could together result in cooling. What follows is the chart for the annual mean precipitation anomaly for Germany:
Germany mean annual precipitation anomaly in hours of sunshine. Data source: DWD here.
Last year, 2018, was one of the driest on and sunniest on record, so it's little wonder that this was a major contributor for a new record annual mean temperature being set.
Over the past 20 years, precipitation over Germany has fallen markedly, which would enhance warming. The last decade has been almost as dry as the decades of the late 19th and early 20th centuries.
Ocean cycles leading to weather pattern changes
We summarize with a chart that superimposes the three charts presented above to ease comparison:
CO2 not the driver
The mechanism for warming over Germany obviously has little to do with heat being trapped by CO2, and much more to do with changing weather patterns that bring changes in sunshine, precipitation and wind direction. Blaming it all on CO2 is wildly adventurous and naive.
Some will argue that CO2 is changing the weather patterns, but this is impossible to confirm and speculative because weather patterns have always been changing.
from Climate Change Skeptic Blogs via hj on Inoreader https://ift.tt/2twopSV
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