March 30, 2019
Magnetic Field, Solar Cycle Influences Climate
Timothy Birdnow
Yes, solar variability does indeed affect the Earth's climate.
From physorg:
How could miniscule changes in incoming solar radiation produce significant climate signatures?
"Soon enough, we realized that the magnitude of the wind anomalies that we detected in observations simply could not be explained by radiative considerations alone. We thought that if it comes from the sun, there must be another mechanism that amplifies the weakening of the Walker circulation," said Prof. Lesley Gray of University of Oxford. With the aid of a global climate model, this mechanism was found in the dynamical coupling between the atmosphere and ocean circulation in the tropical Pacific.
Averaged over the globe, the surface temperature imprint of the solar cycle barely reaches 0.1 K in a solar maximum—almost eight times weaker than the global warming trends observed in the 20th century. Yet, even such a weak surface warming influences the Walker circulation through changes in global hydrology. As the surface warms, water vapor in the atmosphere increases at a higher rate than is lost by precipitation, necessitating a weakening of the Walker cell. This is a well-tested mechanism in model simulations of increased CO2 concentrations but it turns out that is operating under the 11-year solar cycle, too.
S. Misios said, "Our model showed westerly wind anomalies in the Pacific region even when we considered only changes in global hydrology, but the magnitude was far too weak. We hypothesized that atmosphere-ocean coupling, essentially the Bjerknes feedback, can amplify the solar signal."
Our understanding of water vapor and it's effect on climate is still in the horse-and-buggy stage. This clearly illustrates that fact.
Oh, and by the way, we just learned that the sun's magnetic field is ten times stronger than previously believed.
Taken separately these two stories may not seem to amount to much, but together they make a powerful statement about how much we don't know and how these things work together to influence the Earth's climate.
Yes, solar variability does indeed affect the Earth's climate.
From physorg:
An international team of researchers from United Kingdom, Denmark, and Germany has found robust evidence for signatures of the 11-year sunspot cycle in the tropical Pacific. They analyzed historical time series of pressure, surface winds and precipitation with specific focus on the Walker Circulation—a vast system of atmospheric flow in the tropical Pacific region that affects patterns of tropical rainfall. They have revealed that during periods of increased solar irradiance, the trade winds weaken and the Walker circulation shifts eastward.
Stergios Misios, a postdoctoral researcher at the University of Oxford, said, "We deal with a very short record of observations in the tropical Pacific, and we must be very careful with how we filter out other interannual fluctuations. After a careful treatment of the data covering the last 60 years, we detected a robust slowdown of the Walker cell during years associated with solar-cycle maxima." The analysis shows that in tandem with changes in the wind anomalies, the dominant patterns of tropical precipitation shift to the central Pacific during solar-cycle maxima. As a result, rainfall decreases over Indonesia and in the western Pacific, and increases over the central Pacific Ocean.
Stergios Misios, a postdoctoral researcher at the University of Oxford, said, "We deal with a very short record of observations in the tropical Pacific, and we must be very careful with how we filter out other interannual fluctuations. After a careful treatment of the data covering the last 60 years, we detected a robust slowdown of the Walker cell during years associated with solar-cycle maxima." The analysis shows that in tandem with changes in the wind anomalies, the dominant patterns of tropical precipitation shift to the central Pacific during solar-cycle maxima. As a result, rainfall decreases over Indonesia and in the western Pacific, and increases over the central Pacific Ocean.
And how does this work?
How could miniscule changes in incoming solar radiation produce significant climate signatures?
"Soon enough, we realized that the magnitude of the wind anomalies that we detected in observations simply could not be explained by radiative considerations alone. We thought that if it comes from the sun, there must be another mechanism that amplifies the weakening of the Walker circulation," said Prof. Lesley Gray of University of Oxford. With the aid of a global climate model, this mechanism was found in the dynamical coupling between the atmosphere and ocean circulation in the tropical Pacific.
Averaged over the globe, the surface temperature imprint of the solar cycle barely reaches 0.1 K in a solar maximum—almost eight times weaker than the global warming trends observed in the 20th century. Yet, even such a weak surface warming influences the Walker circulation through changes in global hydrology. As the surface warms, water vapor in the atmosphere increases at a higher rate than is lost by precipitation, necessitating a weakening of the Walker cell. This is a well-tested mechanism in model simulations of increased CO2 concentrations but it turns out that is operating under the 11-year solar cycle, too.
S. Misios said, "Our model showed westerly wind anomalies in the Pacific region even when we considered only changes in global hydrology, but the magnitude was far too weak. We hypothesized that atmosphere-ocean coupling, essentially the Bjerknes feedback, can amplify the solar signal."
Our understanding of water vapor and it's effect on climate is still in the horse-and-buggy stage. This clearly illustrates that fact.
Oh, and by the way, we just learned that the sun's magnetic field is ten times stronger than previously believed.
Taken separately these two stories may not seem to amount to much, but together they make a powerful statement about how much we don't know and how these things work together to influence the Earth's climate.
Posted by: Timothy Birdnow at
11:26 AM
| Comments (3)
| Add Comment
Post contains 527 words, total size 4 kb.
1
That's a "for sure," for sure.
A number of years ago, reading an article that had something or other to do with science, I was struck with a remark the author, a prominent scientist, made, which was (I'm quoting loosely because this was, as I said, many years ago) to the effect that "Anytime we write about science, we ought to always preface anything we say with 'at our current stage of ignorance.'" It's a great shame that today's crop of "climate modelers" don't have that kind of humility.
A number of years ago, reading an article that had something or other to do with science, I was struck with a remark the author, a prominent scientist, made, which was (I'm quoting loosely because this was, as I said, many years ago) to the effect that "Anytime we write about science, we ought to always preface anything we say with 'at our current stage of ignorance.'" It's a great shame that today's crop of "climate modelers" don't have that kind of humility.
Posted by: Dana Mathewson at March 30, 2019 01:40 PM (rIYC+)
2
Yes indeed, Dana! Imagine if you were to go back in time to say, 1840, and began talking about Relativity and Quantum Mechanics. They would have thought you were a nut. It wasn't that Einstein was wrong or Quantum Mechanics was nonsense, but the best minds of the day didn't know about it yet. And, no offense, but I doubt you or I could convince them as neither of us are qualified to do the complicated equations to show how it works. The state of ignorance at that time didn't change the reality. That is essentially what the Climate Alarmists are insisting, that if they don't understand it it isn't real. So, if physicists thought then as our climate people do now, we would still be teaching Newton as the final word on physics.
Science is an ever-evolving thing, not "settled".
Science is an ever-evolving thing, not "settled".
Posted by: Timothy Birdnow at March 31, 2019 11:13 AM (1eXJd)
3
To be a viable leader in the present serious working environment, you need to go past the quantitative and embrace practices that will lead you, and your group, to more prominent achievement CLIK HERE.
Posted by: Christa R. Palmer at September 25, 2020 12:52 AM (iaoan)
26kb generated in CPU 0.0229, elapsed 0.2694 seconds.
37 queries taking 0.2527 seconds, 174 records returned.
Powered by Minx 1.1.6c-pink.
37 queries taking 0.2527 seconds, 174 records returned.
Powered by Minx 1.1.6c-pink.
