Pierre Gosselin writes:
Here’s something you don’t witness very often…German national public radio telling listeners that natural factors are behind observed changes in something related to climate.
I can’t tell you how many times I’ve heard the German media claim storms are linked to our disdainful energy gluttony. So it comes as quite a shock when you hear something about climate that doesn’t conform to Potsdam Institute dogmatism.
At their Die kalte Sonne site here, Dr. Sebastian Lüning and Prof. Fritz Vahrenholt bring up an example of how German DLF national radio. I’ve translated the German text:
A team of researchers at the US Department of Energy and the Pacific Northwest National Laboratory recently made an exciting discovery: Apparently, hurricanes are developing more quickly today than they did 30 years ago. Earlier it took longer, but now maximum strength is reached sooner.
The scientists have found the culprit – drum roll – no, it’s not the wanton activity of mankind, rather it’s the Atlantic AMO ocean cycle, which fluctuates with a period of 60 years. During the course of the AMO cycle, hurricanes change accordingly.
Here’s the press release from May 9, 2018:
Powerful hurricanes strengthen faster now than 30 years ago
The storms intensify more rapidly today due largely to a natural climate phenomenon
Hurricanes that intensify rapidly — a characteristic of almost all-powerful hurricanes — do so more strongly and quickly now than they did 30 years ago, according to a study published recently in Geophysical Research Letters, a journal of the American Geophysical Union.
While many factors are at play, the chief driver is a natural phenomenon that affects the temperature of the waters in the Atlantic where hurricanes are powering up, according to scientists at the U.S. Department of Energy’s Pacific Northwest National Laboratory and the National Oceanic and Atmospheric Administration.
They found that a climate cycle known as the Atlantic Multidecadal Oscillation or AMO is central to the increasing intensification of hurricanes, broadly affecting conditions like sea temperature that are known to influence hurricanes.
Stronger hurricanes in a day’s time
Last year’s lineup of powerful storms — Harvey, Irma, Jose, and Maria — spurred the scientists to take a close look at the rapid intensification process. This occurs when the maximum wind speed in a hurricane goes up by at least 25 knots (28.8 miles per hour) within a 24-hour period. It’s a rite of passage for nearly all major hurricanes, including the big four of 2017.
The team, comprised of Karthik Balaguru and Ruby Leung of PNNL and Greg Foltz of NOAA, analyzed 30 years’ worth of satellite hurricane data encompassing 1986 through 2015. The information came from NOAA’s National Hurricane Center and the U.S. Navy’s Joint Typhoon Warning Center.
Consistent with other studies, the scientists did not find that rapid intensification is happening more often nowadays.
But the scientists also looked closely at just how much the storms are strengthening. They found a sizeable jump in the strength of fast-growing storms — the storms are getting more powerful more quickly within a 24-hour period than they were 30 years ago.
The team found that the average boost in wind speed during a 24-hour intensification event is about 13 mph more than it was 30 years ago — on average about 3.8 knots (4.3 mph) for each of the three decades studied.
Several factors play a role when a hurricane gains more power rapidly, including the temperature of the surface of the ocean, humidity, characteristics of the clouds, the heat content in the ocean, and the direction of the wind at the surface compared to miles above. Among the biggest factors affecting the increase in magnitude in the last 30 years, according to the team’s analysis:
- The amount of heat available in the uppermost layer of the ocean, known as the ocean heat content. The warmer the upper ocean, the more powerful a hurricane can become.
- Wind shear: The less the vertical wind shear — the difference in the direction and force of the winds at the surface compared to several miles into the air — the more powerful the hurricane can become.
The influence of the Atlantic Multidecadal Oscillation
The team found that the biggest factor explaining the increasingly rapid intensification is the AMO. The result comes in part from analyses using 16 separate climate models to isolate the impact of global warming.
“This was a surprise, that the AMO seems to be a bigger influence in rapid intensification than other factors, including overall warming,” said Balaguru, the first author of the paper.
The AMO governs how the temperature of the waters in the North Atlantic cycles between warmer and cooler, with each period typically lasting a decade or more.
The cycling occurs for reasons scientists don’t completely understand, but it has broad effects on the environment.
For example, it plays a big part in determining the heat content of the oceans, an important factor powering hurricanes. The AMO has generally been “positive” — causing warmer waters — since the late 1990s.
Balaguru noted that while rapid intensification historically has occurred more often in the western Atlantic, that’s not where the team found the increasing strength of the last 30 years.
Rather, the phenomenon is strengthening more in the central and eastern Atlantic, especially to the east of the islands of the Lesser Antilles, which includes the Virgin Islands and Saint Kitts.
That’s the same area where the AMO creates warmer waters and boosts ocean heat content, in the central and eastern Atlantic.
That’s exactly the alley where hurricanes Irma, Jose and Maria powered up rapidly last year. It’s a proving ground of sorts where many of the most powerful hurricanes strengthen dramatically.
Balaguru notes that teasing out the effects of the AMO from broader effects of global warming was beyond the scope of the current study but is a focus for scientists.”
Even the IPCC-trumpeting Deutschlandfunk (DLF) found this worth reporting. On May 9, 2018, listeners indeed heard on the daily program “Forschung Aktuell” (Current Research) the following points:
- Despite climate change, hurricanes have not become more frequent (which totally contradicts the usual DLF claims on this subject).
- The current faster strengthening of hurricanes has NOTHING to do with anthropogenic global warming (AGW), but rather it depends on the AMO phase.
- The causes of the AMO cycles are unknown and have nothing to do with AGW.
Yet, it is a pity that these revolutionary climate-realist claims (by DLF standards) were presented in just a very short report and that the inconvenient facts were not reported on in greater detail…you can listen to this small DLF revolution here (starting at 1:33).
Don’t hold your breath thinking this is a new media awakening happening in Germany.
Expect Stefan Rahmstorf of the alarmist Potsdam Vatican to order the science illiterate DLF editors to be led deep down somewhere in the catacombs, and be made to recant the heresy.
Full story at No Tricks Zone