Model Alarmists Resurrect ‘Day After Tomorrow’ Scenario, ‘Unsupported By Any Data’
In this newsletter:
1) Solar Activity Crashes
Robert Zimmerman, Behind The Black, 9 April 2018
2) Model Alarmists Resurrect ‘Day After Tomorrow’ Scenario, ‘Unsupported By Any Data’
Michael Bastasch, Daily Caller, 11 April 2018
3) NASA Observations Refute Claims Atlantic ‘Conveyor Belt’ Has Been Slowing
Watts Up With That, 11 April 2018
4) NASA Study Finds Atlantic ‘Conveyor Belt’ Not Slowing
NASA, 25 March 2010
5) On The Long-Term Stability Of Gulf Stream Transport Based On 20 Years Of Direct Measurements
Geophysical Research Letters, 14 December 2013
6) Ocean Array Alters View Of Atlantic ‘Conveyor Belt’
By Katherine Kornei, Science Feb. 17, 2018
Full details:
1) Solar Activity Crashes
Robert Zimmerman, Behind The Black, 9 April 2018
It surely looks like the solar minimum has arrived, and it has done so far earlier than expected!
On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for March 2018. Below is my annotated version of that graph.
March 2018 was the least active month for sunspots since the middle of 2009, almost nine years ago. In fact, activity in the past few months has been so low it matches the low activity seen in late 2007 and early 2008, ten years ago when the last solar minimum began and indicated by the yellow line that I have added to the graph below. If the solar minimum has actually arrived now, this would make this cycle only ten years long, one of the shortest solar cycles on record. More important, it is a weak cycle. In the past, all short cycles were active cycles. This is the first time we have seen a short and weak cycle since scientists began tracking the solar cycle in the 1700s, following the last grand minimum in the 1600s when there were almost no sunspots.
The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.
The graph [above], courtesy of the Sunspot Index and Long-term Solar Observations webpage (SILSO), will give you an idea how little activity occurred in March. There were only five days during the entire month where sunspots could be seen on the visible hemisphere of the Sun. We have not seen so little activity since 2009, when the Sun was in the middle of its sunspot minimum.
We could still see a recovery in sunspot cycle. Past cycles tended to ramp down slowly to solar minimum, not quickly as we have so far seen with this cycle. For example, look at sunspot activity during 2007 on the NOAA graph above. Though activity was dropping, throughout the year there were new bursts of activity, thus holding off the arrival of the minimum. It would not be surprising or unusual to see this happen now. […]
The big question remains: Are we about to head into a grand minimum, as happened during the Maunder Minimum in the 1600s? During that century there were practically no sunspots. Since it occurred immediately after the invention of the telescope, astronomers had no idea that the lack of sunspots were unusual and did not give it much attention. It wasn’t until the solar cycle resumed in the 1700s that they discovered its existence, and thus realized the extraordinary nature of the century-long minimum that had just ended. Unfortunately, it was over, and the chance to study it was gone.
Thus, if a new grand minimum is about to start, it will be a once-in-a-lifetime opportunity for today’s solar scientists. Not only will they will get to study the Sun as it behaves in a manner they have not seen before, they will be able to do it with today’s phalanx of space-based observatories. The chance to gain a better understanding of the Sun will be unprecedented.
Furthermore, the occurrence of a grand minimum now would help the climate field. We really do not know the full influence of the Sun’s solar cycles on the Earth’s climate. There is ample circumstantial evidence that it has a significant impact, such as the Little Ice Age that occurred during the last grand minimum, as well as the unusually cold climates that also matched past weak cycles, now, and also in the early 19th and 20th centuries.
Studying a grand minimum with today’s sophisticated instruments could help measure precisely how much the Sun’s sunspot activity, or lack thereof, changes the climate here on Earth.
Full post
2) Model Alarmists Resurrect ‘Day After Tomorrow’ Scenario, ‘Unsupported By Any Data’
Michael Bastasch, Daily Caller, 11 April 2018
Scientists relied on climate models, not direct measurements, to claim in a new study man-made global warming caused a slowdown in the Gulf Stream ocean current.
It’s the very same scenario posed in disaster movie “The Day After Tomorrow,” where a slowdown in the Gulf Stream turned North America into a frozen wasteland. A catastrophic scenario could be decades away, some scientists are saying.
“We know somewhere out there is a tipping point where this current system is likely to break down,” Potsdam Institute climate scientist Stefan Rahmstorf, a co-author of one of the studies, said in a statement.
“We still don’t know how far away or close to this tipping point we might be,” Rahmstorf warned. “This is uncharted territory.”
Rahmstorf’s study was one of two that garnered alarming media headlines, but experts are skeptical because of the scant observational evidence. Indeed, scientists have only been taking direct measurements of the Gulf Stream for a little over a decade.
“Climate model reconstructions are not the same as observed data or evidence,” libertarian Cato Institute’s Dr. and Atmospheric Scientist Ryan Maue told The Daily Caller News Foundation.
“We should be very wary of grandiose claims of ‘A Day After Tomorrow’ based upon very limited direct measurements,” Maue said.
The Gulf Stream, or Atlantic meridional overturning circulation (AMOC), brings warm water from the Gulf of Mexico to the North Atlantic, and in turn, cold northern water is brought southward.
Polar ice melt and enhanced rainfall put an increasing amount of cold, fresh water into the North Atlantic, reducing salinity, some scientists say. Less saline has a harder time sinking, throwing off the AMOC.
Climate models generally show a weaker AMOC as a result of warming, but observational evidence has been scant. Anomalous cooling south of Greenland is evidence of a weakened AMOC, some scientists say.
The weak AMOC is explicitly tied to “increasing atmospheric carbon dioxide concentrations” and “temperature trends observed since the late nineteenth century,” according to the study, Rahmstorf co-authored.
However, the “Labrador Sea deep convection and the AMOC have been anomalously weak over the past 150 years or so … compared with the preceding 1,500 years,” a second study published in the same journal found.
In other words, the AMOC began weakening before human activities could play a role.
“The specific trend pattern we found in measurements looks exactly like what is predicted by computer simulations as a result of a slowdown in the Gulf Stream System, and I see no other plausible explanation for it,” Rahmstorf, whose study relied on proxy-data from ocean sediment and calcareous shells, said.
But again, there’s limited observational evidence. Several scientists besides Maue were skeptical of Rahmstorf’s study.
Rahmstorf’s “assertions of weakening are conceivable but unsupported by any data,” Massachusetts Institute of Technology’s Carl Wunsch told The Associated Press.
Full story
3) NASA Observations Refute Claims Atlantic ‘Conveyor Belt’ Has Been Slowing
Watts Up With That, 11 April 2018
Yesterday’s “The Day After Tomorrow” climate explainer’s excuse for cold winters is back – research suggests that the North Atlantic current is weaker than anytime for the last 1000 years
Climate Change Dials Down Atlantic Ocean Heating System
By Victoria Gill
Science correspondent, BBC News
11 April 2018
A significant shift in the system of ocean currents that helps keep parts of Europe warm could send temperatures in the UK lower, scientists have found.
They say the Atlantic Ocean circulation system is weaker now than it has been for more than 1,000 years – and has changed significantly in the past 150.
The study, in the journal Nature, says it may be a response to increased melting ice and is likely to continue.
Researchers say that could have an impact on Atlantic ecosystems.
Scientists involved in the Atlas project – the largest study of deep Atlantic ecosystems ever undertaken – say the impact will not be of the order played out in the 2004 Hollywood blockbuster The Day After Tomorrow.
But they say changes to the conveyor-belt-like system – also known as the Atlantic Meridional Overturning Circulation (Amoc) – could cool the North Atlantic and north-west Europe and transform some deep-ocean ecosystems.
That could also affect temperature-sensitive species like coral, and even Atlantic cod.…
Read more: https://www.bbc.com/news/amp/science-environment-43713719
The abstract of the paper;
Observed fingerprint of a weakening Atlantic Ocean overturning circulation
L. Caesar, S. Rahmstorf, A. Robinson, G. Feulner & V. Saba
The Atlantic meridional overturning circulation (AMOC)—a system of ocean currents in the North Atlantic—has a major impact on climate, yet its evolution during the industrial era is poorly known owing to a lack of direct current measurements. Here we provide evidence for a weakening of the AMOC by about 3 ± 1 sverdrups (around 15 per cent) since the mid-twentieth century. This weakening is revealed by a characteristic spatial and seasonal sea-surface temperature ‘fingerprint’ — consisting of a pattern of cooling in the subpolar Atlantic Ocean and warming in the Gulf Stream region—and is calibrated through an ensemble of model simulations from the CMIP5 project. We find this fingerprint both in a high-resolution climate model in response to increasing atmospheric carbon dioxide concentrations, and in the temperature trends observed since the late nineteenth century. The pattern can be explained by a slowdown in the AMOC and reduced northward heat transport, as well as an associated northward shift of the Gulf Stream. Comparisons with recent direct measurements from the RAPID project and several other studies provide a consistent depiction of record-low AMOC values in recent years.
Read more (paywalled): https://www.nature.com/articles/s41586-018-0006-5
Full post
4) NASA Study Finds Atlantic ‘Conveyor Belt’ Not Slowing
NASA, 25 March 2010
PASADENA, Calif. – New NASA measurements of the Atlantic Meridional Overturning Circulation, part of the global ocean conveyor belt that helps regulate climate around the North Atlantic, show no significant slowing over the past 15 years. The data suggest the circulation may have even sped up slightly in the recent past.…
Until recently, the only direct measurements of the circulation’s strength have been from ship-based surveys and a set of moorings anchored to the ocean floor in the mid-latitudes. Willis’ new technique is based on data from NASA satellite altimeters, which measure changes in the height of the sea surface, as well as data from Argo profiling floats. The international Argo array, supported in part by the National Oceanic and Atmospheric Administration, includes approximately 3,000 robotic floats that measure temperature, salinity and velocity across the world’s ocean.
With this new technique, Willis was able to calculate changes in the northward-flowing part of the circulation at about 41 degrees latitude, roughly between New York and northern Portugal. Combining satellite and float measurements, he found no change in the strength of the circulation overturning from 2002 to 2009. Looking further back with satellite altimeter data alone before the float data were available, Willis found evidence that the circulation had sped up about 20 percent from 1993 to 2009. This is the longest direct record of variability in the Atlantic overturning to date and the only one at high latitudes.
The latest climate models predict the overturning circulation will slow down as greenhouse gases warm the planet and melting ice adds freshwater to the ocean. “Warm, freshwater is lighter and sinks less readily than cold, salty water,” Willis explained.
For now, however, there are no signs of a slowdown in the circulation. “The changes we’re seeing in overturning strength are probably part of a natural cycle,” said Willis. “The slight increase in overturning since 1993 coincides with a decades-long natural pattern of Atlantic heating and cooling.”…
Read more: https://www.nasa.gov/topics/earth/features/atlantic20100325.html
5) On The Long-Term Stability Of Gulf Stream Transport Based On 20 Years Of Direct Measurements
Geophysical Research Letters, 14 December 2013
T. Rossby, C. N. Flagg, K. Donohue, A. Sanchez-Franks, J. Lillibridge
Abstract
In contrast to recent claims of a Gulf Stream slowdown, two decades of directly measured velocity across the current show no evidence of a decrease. Using a well-constrained definition of Gulf Stream width, the linear least square fit yields a mean surface layer transport of 1.35 × 105 m2 s−1 with a 0.13% negative trend per year. Assuming geostrophy, this corresponds to a mean cross-stream sea level difference of 1.17 m, with sea level decreasing 0.03 m over the 20 year period. This is not significant at the 95% confidence level, and it is a factor of 2–4 less than that alleged from accelerated sea level rise along the U.S. Coast north of Cape Hatteras. Part of the disparity can be traced to the spatial complexity of altimetric sea level trends over the same period.
http://onlinelibrary.wiley.com/doi/10.1002/2013GL058636/abstract
6) Ocean Array Alters View Of Atlantic ‘Conveyor Belt’
By Katherine Kornei, Science Feb. 17, 2018
PORTLAND, OREGON—Oceanographers have put a stethoscope on the coursing circulatory system of the Atlantic Ocean, and they have found a skittish pulse that’s surprisingly strong in the waters east of Greenland—discoveries that should improve climate models.
The powerful currents known as the Atlantic meridional overturning circulation (AMOC) are an engine in Earth’s climate. The AMOC’s shallower limbs—which include the Gulf Stream—move warm water from the tropics northward, warming Western Europe. In the north, the waters cool and sink, forming deeper limbs that transport the cold water back south—and sequester anthropogenic carbon in the process. This overturning is why the AMOC is sometimes called the Atlantic conveyor belt.
Last week, at the American Geophysical Union’s Ocean Sciences meeting here, scientists presented the first data from an array of instruments moored in the subpolar North Atlantic. The observations reveal unexpected eddies and strong variability in the AMOC currents. They also show that the currents east of Greenland contribute the most to the total AMOC flow. Climate models, on the other hand, have emphasized the currents west of Greenland in the Labrador Sea. “We’re showing the shortcomings of climate models,” says Susan Lozier, a physical oceanographer at Duke University in Durham, North Carolina, who leads the $35 million, seven-nation project known as the Overturning in the Subpolar North Atlantic Program (OSNAP). […]
At the meeting, researchers working with the 21 moorings of the 26°N array also released their latest findings, which include measurements through February 2017. They show that the AMOC has weakened by about 15% compared with its 2004–08 level. Some climate models have raised the specter of a sudden shutdown of the AMOC—the apocalyptic scenario, leading to a frozen Europe, depicted in the 2004 movie The Day After Tomorrow—and the possibility is also supported by evidence from the geological past. But the decline in the AMOC hasn’t persisted long enough yet to be a cause for concern, says David Smeed, a physical oceanographer at the National Oceanography Centre in Southampton, U.K.
The overall trend of the AMOC will become clearer with time. This summer, researchers on the R/V Neil Armstrong will pull up OSNAP moorings and retrieve readings recorded from 2016–18.
The London-based Global Warming Policy Forum is a world leading think tank on global warming policy issues. The GWPF newsletter is prepared by Director Dr Benny Peiser - for more information, please visit the website at www.thegwpf.com.
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