New studies confirm: Glaciers in the Alps already had “fevers” during the Roman and Medieval warm periods
By Sebastian Lüning and Fritz Vahrenholt
(Translated, edited, condensed by P Gosselin)
Everywhere activists and climate alarmists are claiming climate change is happening faster than ever and that the earth is dangerously approaching a tipping point. For example Greenpeace likes to say that the glaciers are actually the “fever thermometers” measuring the health of the planet and that their melting tells the story of inevitable total meltdown. For example in the Alps glaciers have receded by almost a half since the year 1850. Greenpeace writes:
Foremost since the 1990s the rate of melt has increased and is expected to rise over the coming years: Today’s melting is being caused by greenhouse gas emissions from 30 years ago.”
But is glacier melt really something new and unexpected?
Greenpeace uses the Alps as a telltale example. It is precisely there that we want to carry out a fact-check. Firstly one has to wonder why the glacier melt in the Alps began already way back in 1850 – when anthropogenic CO2 couldn’t have played any significant role. This was already determined by geologist Albert Schreiner in 1997 in his textbook “Introduction to Quatenary Geology“ (p. 188, Fig. 91).
One finds even greater factual headaches when going back through the history of the climate for the last several thousand years. Already in earlier articles we wrote that the Alps glacier melted considerably during earlier warm periods.
The melt phases during the Medieval Warm Period 1000 years ago and during the Roman Warm Period 2000 years ago have been well documented (see our blog articles here and here. In April 2014 two more additional papers were published, which impressively confirmed the natural glacier dynamics.
In the Quaternary Science Reviews appeared a paper authored by a team led by Anaëlle Simonneau of the French University Orléans, which reconstructed the glacier movements in the French Alps over the last thousands of years. Here the scientists documented several glacier melt phases, which unsurprisingly included the Roman and Medieval warm periods (Figure1). What follows is an excerpt from the abstract:
Holocene palaeoenvironmental evolution and glacial fluctuations at high-altitude in the western French Alps are reconstructed based on a multiproxy approach within Lake Blanc Huez (2550 m a.s.l.) drainage basin. […] periods of reduced glacial activities dated from the Early Bronze Age (ca 3870–3770 cal BP), the Iron Age (ca 2220–2150 cal BP), the Roman period (ca AD115–330) and the Medieval Warm Period (ca AD760–1160).”
Figure 1: Reconstruction of glacier activity in the French Alps. The glacier advances are shown in blue and melt periods in red. The scale is in 1000s of years before today. The Medieval Warm Period is at 1 (=1000 years before today), the Roman Warm Period is at 2 (=2000 years before today). Moreover: In the time from 6000 to 9000 years before today there was massive glacier melting. Source: Simonneau et al. 2014.
A second paper comes from Martin Lüthi of the University of Zurich, appearing in The Cryosphere. It contains a reconstruction of the Alps glacier history for the last 1600 years. Interestingly the seven examined glaciers show conditions during the Medieval Warm Period that were similar in length as today (Figure 2).
Figure 2: Length changes in Alps glaciers over the past 1600 years. The blue negative vertical bars depict advancing glaciers while the red bars represent retreating glaciers. From Lüthi 2014.
Despite these proven natural glacier cycles, Greenpeace Greenpeace predicts an early death and terrible consequences for the Alps:
Glacier scientists anticipate an almost complete melting in this century. There are 5000 glaciers in the Alps. When many of them are permanently melted, there could be a sensitive collapse in the water supply. Glaciers store drinking water.
A scary theory. However the glaciers are ignoring all the catastrophe predictions and even started to grow once again in 2013, see here. And in the Swiss Alps snow amounts since 2000 have unexpectedly been on the rise.
A look back at the climate history reveals that the alarmist stories for the Alps are nothing but a tempest in a teapot. It’s all happened before. Obviously the fear-mongers have failed to look beyond 150 years ago. How much longer can they keep this up without serious science pushing back?