A recent article in the journal Science has provided a new, detailed climate record for the Medieval Climate Anomaly (MCA), also know as the Medieval Warm Period. It was the most recent pre-industrial warm period, noted in Europe and elsewhere around the globe. The researchers present a 947-year-long multi-decadal North Atlantic Oscillation (NAO) reconstruction and find a persistent positive NAO during the MCA. The interesting thing is that the MCA had basically been removed from the climate record by Michael Mann's infamous “hockey stick” history graph that was adopted by the IPCC a decade ago.
The current hot phrase bandied about by talking heads and parotted by news pundits is “tipping point.” We are told that the climate may be near a tipping point, if it has not crossed one already, and that can't be good. But what is a tipping point, where do they come from and how can we identify one when we see it?
Historical records for the western Antarctic Peninsula (WAP) show that it is particularly prone to rapid climate change—change that occurs in cycles of ~200 years and ~2500 years. By studying major transitions in plankton productivity in the western Antarctic, scientists have shown that “spectacular” ice-cover losses have happened many times in the past. In other words, the “unprecedented rapid loss of ice” from parts of Antarctica that global warming alarmists make so much of are a normal part of nature's cycles.
One of the catastrophic results of global warming always cited by climate change alarmists is the melting of the ice sheets covering Greenland. Some even speculated that global warming had pushed Greenland past a “tipping point” into a scary new regime of wildly heightened ice loss and rapidly rising in sea levels. Now, from the fall meeting of the American Geophysical Union, comes word that Greenland's Ice Armageddon has been called off.
Here are some interesting climate related tidbits from the science news feeds; food for thought in the new year. First, researchers at the University of Oregon have discovered evidence linking the disappearance of North American megafauna, the Clovis people and the onset of the Younger Dryas period to a comet impact. For years scientists have blamed the disappearance of the American Mammoth, Mastodon, saber toothed cats and other large land animals on human predation or climate change.