By Dr. Sebastian Lüning and Prof. Fritz Vahrenholt
(German text translated/edited by P. Gosselin)
On June 29, 2016 the University of Delaware (UD) unleashed a climate penguin panic with its press release:
Penguins and climate change:
UD scientists report projected response of Adélie penguins to Antarctic climate change
It’s a big question: how is climate change in Antarctica affecting Adélie penguins? Climate has influenced the distribution patterns of Adélie penguins across Antarctica for millions of years. The geologic record tells us that as glaciers expanded and covered Adélie breeding habitats with ice, penguin colonies were abandoned. When the glaciers melted during warming periods, this warming positively affected the Adélie penguins, allowing them to return to their rocky breeding grounds. But now, University of Delaware scientists and colleagues report that this beneficial warming may have reached its tipping point. In a paper published today in Scientific Reports, the researchers project that approximately 30 percent of current Adélie colonies may be in decline by 2060 and approximately 60 percent may be in decline by 2099.”
That’s absolutely bitter. More than half of the penguins will be dead by 2099. In earlier times they benefitted from climate warming, but today heat is threatening to wipe them out. How has this come to be? The press release continues:
It is only in recent decades that we know Adélie penguins population declines are associated with warming, which suggests that many regions of Antarctica have warmed too much and that further warming is no longer positive for the species,” said the paper’s lead author Megan Cimino, who earned her doctoral degree at UD in May.”
Antarctica has warmed unusually over the past decades?
Assessing recent trends in high-latitude Southern Hemisphere surface climate
Understanding the causes of recent climatic trends and variability in the high-latitude Southern Hemisphere is hampered by a short instrumental record. Here, we analyse recent atmosphere, surface ocean and sea-ice observations in this region and assess their trends in the context of palaeoclimate records and climate model simulations. Over the 36-year satellite era, significant linear trends in annual mean sea-ice extent, surface temperature and sea-level pressure are superimposed on large interannual to decadal variability. However, most observed trends are not unusual when compared with Antarctic paleoclimate records of the past two centuries. With the exception of the positive trend in the Southern Annular Mode, climate model simulations that include anthropogenic forcing are not compatible with the observed trends. This suggests that natural variability likely overwhelms the forced response in the observations, but the models may not fully represent this natural variability or may overestimate the magnitude of the forced response.“
Perhaps the penguin researchers should first take a better look at this paper as soon as it gets published officially. It becomes necessary to explain why the Adélie-penguins are even alive today because the Antarctic Peninsula was warmer than today many times over the past thousands of years. By the way, the last warm phase in Antarctica occurred as an effect of the Medieval Warm Period.
When one looks more closely at the University of Delaware paper, the tricks the penguin researches are using quickly becomes clear. For assessing the danger, a middle of the pack climate model scenario was not used. No, instead the absolute most grim model by the name of RCP 8.5 was used. It just could not be worse. It’s like being sure you’ll have a car accident on the way to work today.