German Scientists: “Nothing unusual” about late 20th Century warming

Anyone paying attention to the news knows that there is ongoing debate in the scientific community about the cause of global warming and climate skeptics seem to be winning. Two persuasive studies by German physicists Horst-Joachim Lüdecke, Alexander Hempelmann and Carl Otto Weiss were published recently in the journal European Geophysical Union. The first manuscript, published two years ago, investigated climate history of the past 250 years. The second, published this year, outlined the protracted analysis for the last 25 centuries or 2500 years.

As opposed to the politicized aspects of climate science stating humans influence climate change, the German scientist’s conclusion is consistent with the present day main body of research.

The analysis of the past 2500 years involved data from tree rings, sediment cores, stalagmites, etc. A plot of the data yields a climate operating with cyclic behavior.


Compared to the maxima and minima of the past, the current minima and maxima show that there is nothing unusual happening today. The scientists say today’s temperature changes are within the normal range. The German authors write: “Especially the 20th century shows nothing out of the ordinary.”

Lüdecke, Hempelmann, and Weiss assert that over the next 60 years there is a probable likelihood of global cooling:

The German scientists write that one result of the well established cyclic behavior over the past 2500 years is that it is justified to assume that the De Vries / Suess solar cycle will continue in the future.

They write that this means that “global cooling is to be expected over the next 60 years (Figure 3)”.


All three physicists checked the oldest, consistent thermostat datasets over the previous 250 years, including ice cores and stalagmites. The only thing found was cyclic or periodic shifts:

Lüdecke, Hempelmann and Weiss also examined the oldest existing thermometer datasets going back some 250 years taken at the locations of Kremsmünster, Vienna, Prague, Hohenpeißenberg, Munich and Paris. Their study also included ice cores and stalagmite datasets, which the scientists say “show exclusively periodic climate changes in fine detail. There is no trace of aperiodic effects, such as from the continuously rising CO2 concentration in the atmosphere (Figure 4).”


Despite our living in a period of very low temperatures, Lüdecke, Hempelmann and Weiss state since the end of the Little Ice Age, there has been a period of slight warming. The authors state regarding this:

The German trio of scientists says the 0.7°C of warming occurring since the late 19th century is the result of the increase in the De Vries / Suess solar cycle and that the well-known oceanic AMO/PDO oscillations can also be seen. “These two cycles practically determine by themselves the earth’s temperature.”

The scientists add that the “pause“ in global warming is caused by the AMO/PDO, which has been on the decline since 2000. The De Vries / Suess solar cycle allows a general cooling up to the year 2080 to be predicted and that the global temperature will reach a level last seen in 1870.

The three authors, however, could not close their manuscript out with take a pot shot at climate alarmists either. They reveal that 50% of the temperature increase expected to happen by 2100 should have taken place by now – if such a CO2 warming were true. The scientists say that the way things stand now, if the CO2 effect were real, the future warming up to the year 2100 could be at most 0.7 °C.

The controversy caused by the Old Farmer’s Almanac this month prompted me to look at The Farmer’s Almanac forecast for this year. As it turns out, the journal correctly predicted 2014’s cold, frigid weather and recently forecasted a repeat of last year’s weather with the northeastern United States getting unusually snowy and cold. If last year’s frigid cold temperatures in the regions the Almanac predicts a cold winter this year is any indication, increased atmospheric CO2 raising Earth’s temperature by less than a degree won’t make any difference.