Low Solar activity cycle and temperature changes
The sun's current space-weather cycle is the most anemic in 100 years, scientists say.
Our star is now at "solar maximum," the peak phase of its 11-year activity cycle. But this solar max is weak, and the overall current cycle, known as Solar Cycle 24, conjures up comparisons to the famously feeble Solar Cycle 14 in the early 1900s, researchers said.
"None of us alive have ever seen such a weak cycle. So we will learn something," Leif Svalgaard of Stanford University told reporters here today (Dec. 11) at the annual meeting of the American Geophysical Union.
The learning has already begun. For example, scientists think they know why the solar storms that have erupted during Solar Cycle 24 have caused relatively few problems here on Earth. . . .
UPDATE: Another interesting study was reported in the Daily Caller:
A Swedish study found that the planet was warmer in ancient Roman times and the Middle Ages than today, challenging the mainstream idea that man-made greenhouse gas emissions are the main drivers of global warming.
The study, by scientist Leif Kullman, analyzed 455 “radiocarbon-dated mega-fossils” in the Scandes mountains and found that tree lines for different species of trees were higher during the Roman and Medieval times than they are today. Not only that, but the temperatures were higher as well.
“Historical tree line positions are viewed in relation to early 21st century equivalents, and indicate that tree line elevations attained during the past century and in association with modern climate warming are highly unusual, but not unique, phenomena from the perspective of the past 4,800 years,” Kullman found. “Prior to that, the pine tree line (and summer temperatures) was consistently higher than present, as it was also during the Roman and Medieval periods.”
Kullman also wrote that “summer temperatures during the early Holocene thermal optimum may have been 2.3°C higher than present.” The “Holocene thermal optimum was a warm period that occurred between 9,000 and 5,000 years ago. This warm period was followed by a gradual cooling period.” . . .