Scientists Find Missing Link Between Exploding Stars, Clouds, And Climate On Earth
In this newsletter:
1) New Study: Cosmic Rays, Solar Activity Have Much Greater Impact On Earth’s Climate Than Models Suggest
Graham Lloyd, The Australian, 19 December 2017
2) The Missing Link Between Exploding Stars, Clouds, And Climate On Earth
Technical University of Denmark, 19 December 2017
3) David Whitehouse: Cosmic Rays-Climate Link Found
GWPF Observatory, 19 December 2017
4) Sun May Be Dimming: NASA Launches New Probe To Confirm Declining Luminosity
International Business Times, 17 December 2017
Full details:
1) New Study: Cosmic Rays, Solar Activity Have Much Greater Impact On Earth’s Climate Than Models Suggest
Graham Lloyd, The Australian, 19 December 2017
The impact of changes in solar activity on Earth’s climate was up to seven times greater than climate models suggested according to new research published today in Nature Communications.
Researchers have claimed a breakthrough in understanding how cosmic rays from supernovas react with the sun to form clouds, which impact the climate on Earth.
The findings have been described as the “missing link” to help resolve a decades long controversy that has big implications for climate science.
Lead author, Henrik Svensmark, from The Technical University of Denmark has long held that climate models had greatly underestimated the impact of solar activity.
He says the new research identified the feedback mechanism through which the sun’s impact on climate was varied.
Professor Svensmark’s theories on solar impact have caused a great deal of controversy within the climate science community and the latest findings are sure to provoke new outrage.
He does not dispute that increased levels of carbon dioxide in the atmosphere have a warming impact on the climate.
But his findings present a challenge to estimates of how sensitive the climate is to changes in carbon dioxide levels in the atmosphere.
Professor Svensmark says his latest findings were consistent both with the strong rise in the rate of global temperature change late last century and a slowdown in the rate of increase over the past 20 years.
‘’It gives a physical foundation to the large body of empirical evidence showing that solar activity is reflected in variations in Earth’s climate,” a media statement accompanying the scientific report said.
“For example, the Medieval Warm Period around year 1000AD and the cold period in the Little Ice Age 1300-1900 AD both fits changes in solar activity,” it said.
“Finally we have the last piece of the puzzle of why the particles from space are important for climate on Earth,” it said.
The study reveals how atmospheric ions, produced by the energetic cosmic rays raining down through the atmosphere, helps the growth and formation of cloud condensation nuclei — the seeds necessary for forming clouds in the atmosphere.
More cloud condensation nuclei mean more clouds and a colder climate, and vice versa.
“Since clouds are essential for the solar energy reaching the surface of the Earth the implications are huge for our understanding of why climate has varied in the past and also for a future climate changes,” the statement said.
Professor Svensmark said it had until now wrongly been assumed that small additional nucleated aerosols would not grow and become cloud condensation nuclei, since no mechanism was known to achieve this.
The research team tested its ideas experimentally in a large cloud chamber.
Data was taken over a period of two years with total 3100 hours of data sampling.
Professor Svensmark said the new results gave a physical foundation to the large body of empirical evidence showing that Solar activity is reflected in variations in Earth’s climate.
“This new work gives credit to a mechanism that is much stronger than changes in solar irradiance alone,” Svensmark told The Australian.
“Solar irradiance has been the only solar forcing that has been included in climate models and such results show that the effect on climate is too small to be of importance,” he said.
“The new thing is that there exists an amplification mechanism that is operating on clouds in the atmosphere,” Svensmark said.
“Quantifying the impact of solar activity on climate from observations is found to be 5-7 times larger than from solar irradiance, and agrees with empirical variations in cosmic rays and clouds,” he said.
“This can therefore also explain why climate over the last 10,000 years correlates with solar activity, “Svensmark said.
“On time scales of millions of years there are much larger changes in the cosmic rays that has nothing to do with solar activity,” he said.
“So, this is an independent test of the mechanism and even here beautiful correlations are found,” he said.
But the Nature Communications paper says “the theory of ion-induced condensation should be incorporated into global aerosol models, to fully test the atmospheric implications.”
Professor Svensmark said since solar activity increased in the 20th century, part of the observed warming is caused by the sun.
“The logical consequence is that the climate sensitivity of CO2 is smaller than what climate models suggest which is 2-4 deg C for each doubling of CO2, since both CO2 and solar activity has had an impact”, he said.
Full story
2) The Missing Link Between Exploding Stars, Clouds, And Climate On Earth
Technical University of Denmark, 19 December 2017
A breakthrough in the understanding of how cosmic rays from supernovae can influence Earth´s cloud cover and thereby climate is published today in the journal Nature Communications.
Cosmic rays interacting with the Earth's atmosphere producing ions that helps turn small aerosols into cloud condensation nuclei -- seeds on which liquid water droplets form to make clouds. A proton with energy of 100 GeV interact at the top of the atmosphere and produces a cascade of secondary particles who ionize molecules when traveling through the air. One 100 GeV proton hits every m2 at the top of the atmosphere every second. Illustration: H. Svensmark/DTU
The study reveals how atmospheric ions, produced by the energetic cosmic rays raining down through the atmosphere, helps the growth and formation of cloud condensation nuclei – the seeds necessary for forming clouds in the atmosphere. When the ionization in the atmosphere changes, the number of cloud condensation nuclei changes affecting the properties of clouds. More cloud condensation nuclei mean more clouds and a colder climate, and vice versa. Since clouds are essential for the amount of Solar energy reaching the surface of Earth the implications can be significant for our understanding of why climate has varied in the past and also for a future climate changes.
Illustration of cosmic rays interacting with the atmosphere. A proton with energy of 100 GeV interact at the top of the atmosphere and produces a cascade of secondary particles who ionize molecules when traveling through the air. One 100 GeV proton hits every square meter at the top of the atmosphere every second.
Cloud condensation nuclei can be formed by the growth of small molecular clusters called aerosols. It has until now been assumed that additional small aerosols would not grow and become cloud condensation nuclei, since no mechanism was known to achieve this.
The new results reveal, both theoretically and experimentally, how interactions between ions and aerosols can accelerate the growth by adding material to the small aerosols and thereby help them survive to become cloud condensation nuclei. It gives a physical foundation to the large body of empirical evidence showing that Solar activity plays a role in variations in Earth’s climate. For example, the Medieval Warm Period around year 1000 AD and the cold period in the Little Ice Age 1300-1900 AD both fits with changes in Solar activity.
“Finally we have the last piece of the puzzle explaining how particles from space affect climate on Earth. It gives an understanding of how changes caused by Solar activity or by super nova activity can change climate,” says Henrik Svensmark, from DTU Space at the Technical University of Denmark, lead author of the study. Co- authors are senior researcher Martin Bødker Enghoff (DTU Space), Professor Nir Shaviv (Hebrew University of Jerusalem), and Jacob Svensmark, (University of Copenhagen).
The new study
The fundamental new idea in the study is to include a contribution to growth of aerosols by the mass of the ions. Although the ions are not the most numerous constituents in the atmosphere the electro-magnetic interactions between ions and aerosols compensate for the scarcity and make fusion between ions and aerosols much more likely. Even at low ionization levels about 5% of the growth rate of aerosols is due to ions. In the case of a nearby super nova the effect can be more than 50% of the growth rate, which will have an impact on the clouds and the Earth’s temperature.
To achieve the results a theoretical description of the interactions between ions and aerosols was formulated along with an expression for the growth rate of the aerosols. The ideas were then tested experimentally in a large cloud chamber. Due to experimental constraints caused by the presence of chamber walls, the change in growth rate that had to be measured was of the order 1%, which poses a high demand on stability during the experiments, and experiments were repeated up to 100 times in order to obtain a good signal relative to unwanted fluctuations. Data was taken over a period of 2 years with total 3100 hours of data sampling. The results of the experiments agreed with the theoretical predictions.
The hypothesis in a nutshell
Cosmic rays, high-energy particles raining down from exploded stars, knock electrons out of air molecules. This produces ions, that is, positive and negative molecules in the atmosphere.
The ions help aerosols – clusters of mainly sulphuric acid and water molecules – to form and become stable against evaporation. This process is called nucleation. The small aerosols need to grow nearly a million times in mass in order to have an effect on clouds.
The second role of ions is that they accelerate the growth of the small aerosols into cloud condensation nuclei – seeds on which liquid water droplets form to make clouds. The more ions the more aerosols become cloud condensation nuclei. It is this second property of ions which is the new result published in Nature Communications.
Low clouds made with liquid water droplets cool the Earth’s surface.
Variations in the Sun’s magnetic activity alter the influx of cosmic rays to the Earth.
When the Sun is lazy, magnetically speaking, there are more cosmic rays and more low clouds, and the world is cooler.
When the Sun is active fewer cosmic rays reach the Earth and, with fewer low clouds, the world warms up.
The implications of the study suggests that the mechanism can have affected:
* The climate changes observed during the 20th century
* The coolings and warmings of around 2°C that have occurred repeatedly over the past 10,000 years, as the Sun’s activity and the cosmic ray influx have varied.
* The much larger variations of up to 10°C occurring as the Sun and Earth travel through the Galaxy visiting regions with varying numbers of exploding stars.
The authors
Graham Lloyd, The Australian, 19 December 2017
The impact of changes in solar activity on Earth’s climate was up to seven times greater than climate models suggested according to new research published today in Nature Communications.
Researchers have claimed a breakthrough in understanding how cosmic rays from supernovas react with the sun to form clouds, which impact the climate on Earth.
The findings have been described as the “missing link” to help resolve a decades long controversy that has big implications for climate science.
Lead author, Henrik Svensmark, from The Technical University of Denmark has long held that climate models had greatly underestimated the impact of solar activity.
He says the new research identified the feedback mechanism through which the sun’s impact on climate was varied.
Professor Svensmark’s theories on solar impact have caused a great deal of controversy within the climate science community and the latest findings are sure to provoke new outrage.
He does not dispute that increased levels of carbon dioxide in the atmosphere have a warming impact on the climate.
But his findings present a challenge to estimates of how sensitive the climate is to changes in carbon dioxide levels in the atmosphere.
Professor Svensmark says his latest findings were consistent both with the strong rise in the rate of global temperature change late last century and a slowdown in the rate of increase over the past 20 years.
‘’It gives a physical foundation to the large body of empirical evidence showing that solar activity is reflected in variations in Earth’s climate,” a media statement accompanying the scientific report said.
“For example, the Medieval Warm Period around year 1000AD and the cold period in the Little Ice Age 1300-1900 AD both fits changes in solar activity,” it said.
“Finally we have the last piece of the puzzle of why the particles from space are important for climate on Earth,” it said.
The study reveals how atmospheric ions, produced by the energetic cosmic rays raining down through the atmosphere, helps the growth and formation of cloud condensation nuclei — the seeds necessary for forming clouds in the atmosphere.
More cloud condensation nuclei mean more clouds and a colder climate, and vice versa.
“Since clouds are essential for the solar energy reaching the surface of the Earth the implications are huge for our understanding of why climate has varied in the past and also for a future climate changes,” the statement said.
Professor Svensmark said it had until now wrongly been assumed that small additional nucleated aerosols would not grow and become cloud condensation nuclei, since no mechanism was known to achieve this.
The research team tested its ideas experimentally in a large cloud chamber.
Data was taken over a period of two years with total 3100 hours of data sampling.
Professor Svensmark said the new results gave a physical foundation to the large body of empirical evidence showing that Solar activity is reflected in variations in Earth’s climate.
“This new work gives credit to a mechanism that is much stronger than changes in solar irradiance alone,” Svensmark told The Australian.
“Solar irradiance has been the only solar forcing that has been included in climate models and such results show that the effect on climate is too small to be of importance,” he said.
“The new thing is that there exists an amplification mechanism that is operating on clouds in the atmosphere,” Svensmark said.
“Quantifying the impact of solar activity on climate from observations is found to be 5-7 times larger than from solar irradiance, and agrees with empirical variations in cosmic rays and clouds,” he said.
“This can therefore also explain why climate over the last 10,000 years correlates with solar activity, “Svensmark said.
“On time scales of millions of years there are much larger changes in the cosmic rays that has nothing to do with solar activity,” he said.
“So, this is an independent test of the mechanism and even here beautiful correlations are found,” he said.
But the Nature Communications paper says “the theory of ion-induced condensation should be incorporated into global aerosol models, to fully test the atmospheric implications.”
Professor Svensmark said since solar activity increased in the 20th century, part of the observed warming is caused by the sun.
“The logical consequence is that the climate sensitivity of CO2 is smaller than what climate models suggest which is 2-4 deg C for each doubling of CO2, since both CO2 and solar activity has had an impact”, he said.
Full story
2) The Missing Link Between Exploding Stars, Clouds, And Climate On Earth
Technical University of Denmark, 19 December 2017
A breakthrough in the understanding of how cosmic rays from supernovae can influence Earth´s cloud cover and thereby climate is published today in the journal Nature Communications.
Cosmic rays interacting with the Earth's atmosphere producing ions that helps turn small aerosols into cloud condensation nuclei -- seeds on which liquid water droplets form to make clouds. A proton with energy of 100 GeV interact at the top of the atmosphere and produces a cascade of secondary particles who ionize molecules when traveling through the air. One 100 GeV proton hits every m2 at the top of the atmosphere every second. Illustration: H. Svensmark/DTU
The study reveals how atmospheric ions, produced by the energetic cosmic rays raining down through the atmosphere, helps the growth and formation of cloud condensation nuclei – the seeds necessary for forming clouds in the atmosphere. When the ionization in the atmosphere changes, the number of cloud condensation nuclei changes affecting the properties of clouds. More cloud condensation nuclei mean more clouds and a colder climate, and vice versa. Since clouds are essential for the amount of Solar energy reaching the surface of Earth the implications can be significant for our understanding of why climate has varied in the past and also for a future climate changes.
Illustration of cosmic rays interacting with the atmosphere. A proton with energy of 100 GeV interact at the top of the atmosphere and produces a cascade of secondary particles who ionize molecules when traveling through the air. One 100 GeV proton hits every square meter at the top of the atmosphere every second.
Cloud condensation nuclei can be formed by the growth of small molecular clusters called aerosols. It has until now been assumed that additional small aerosols would not grow and become cloud condensation nuclei, since no mechanism was known to achieve this.
The new results reveal, both theoretically and experimentally, how interactions between ions and aerosols can accelerate the growth by adding material to the small aerosols and thereby help them survive to become cloud condensation nuclei. It gives a physical foundation to the large body of empirical evidence showing that Solar activity plays a role in variations in Earth’s climate. For example, the Medieval Warm Period around year 1000 AD and the cold period in the Little Ice Age 1300-1900 AD both fits with changes in Solar activity.
“Finally we have the last piece of the puzzle explaining how particles from space affect climate on Earth. It gives an understanding of how changes caused by Solar activity or by super nova activity can change climate,” says Henrik Svensmark, from DTU Space at the Technical University of Denmark, lead author of the study. Co- authors are senior researcher Martin Bødker Enghoff (DTU Space), Professor Nir Shaviv (Hebrew University of Jerusalem), and Jacob Svensmark, (University of Copenhagen).
The new study
The fundamental new idea in the study is to include a contribution to growth of aerosols by the mass of the ions. Although the ions are not the most numerous constituents in the atmosphere the electro-magnetic interactions between ions and aerosols compensate for the scarcity and make fusion between ions and aerosols much more likely. Even at low ionization levels about 5% of the growth rate of aerosols is due to ions. In the case of a nearby super nova the effect can be more than 50% of the growth rate, which will have an impact on the clouds and the Earth’s temperature.
To achieve the results a theoretical description of the interactions between ions and aerosols was formulated along with an expression for the growth rate of the aerosols. The ideas were then tested experimentally in a large cloud chamber. Due to experimental constraints caused by the presence of chamber walls, the change in growth rate that had to be measured was of the order 1%, which poses a high demand on stability during the experiments, and experiments were repeated up to 100 times in order to obtain a good signal relative to unwanted fluctuations. Data was taken over a period of 2 years with total 3100 hours of data sampling. The results of the experiments agreed with the theoretical predictions.
The hypothesis in a nutshell
Cosmic rays, high-energy particles raining down from exploded stars, knock electrons out of air molecules. This produces ions, that is, positive and negative molecules in the atmosphere.
The ions help aerosols – clusters of mainly sulphuric acid and water molecules – to form and become stable against evaporation. This process is called nucleation. The small aerosols need to grow nearly a million times in mass in order to have an effect on clouds.
The second role of ions is that they accelerate the growth of the small aerosols into cloud condensation nuclei – seeds on which liquid water droplets form to make clouds. The more ions the more aerosols become cloud condensation nuclei. It is this second property of ions which is the new result published in Nature Communications.
Low clouds made with liquid water droplets cool the Earth’s surface.
Variations in the Sun’s magnetic activity alter the influx of cosmic rays to the Earth.
When the Sun is lazy, magnetically speaking, there are more cosmic rays and more low clouds, and the world is cooler.
When the Sun is active fewer cosmic rays reach the Earth and, with fewer low clouds, the world warms up.
The implications of the study suggests that the mechanism can have affected:
* The climate changes observed during the 20th century
* The coolings and warmings of around 2°C that have occurred repeatedly over the past 10,000 years, as the Sun’s activity and the cosmic ray influx have varied.
* The much larger variations of up to 10°C occurring as the Sun and Earth travel through the Galaxy visiting regions with varying numbers of exploding stars.
The authors
Dr. Henrik Svensmark, Danish National Space Institute, in the Technical University of Denmark (DTU).
Senior Resercher Martin Andres Bødker Enghoff, Danish National Space Institute, in the Technical University of Denmark (DTU).
Professor Nir Shaviv, Physics Institute, Hebrew University of Jerusalem.
Ph.D. student Jacob Svensmark, Dark Cosmology Center, University of Copenhagen.
Full journal reference
H. Svensmark, M.B. Enghoff, N. Shaviv and J. Svensmark, Increased ionization supports growth of aerosols into cloud condensation nuclei, Nature Communications DOI: 10.1038/s41467-017-02082-2
Contact
Henrik Svensmark, Danish National Space Institute, in the Technical University of Denmark (DTU).
Journalists can obtain a copy of the paper by writing to hsv@space.dtu.dk
3) David Whitehouse: Cosmic Rays-Climate Link Found
GWPF Observatory, 19 December 2017
Dr David Whitehouse, GWPF Science Editor
Scientists at the Technical University of Denmark have discovered what they call a game changing result in understanding how cosmic rays from supernovae – exploding stars – can influence Earth’s cloud cover and thereby climate by being mediated by the Sun. The new findings are published in the journal Nature Communications. If confirmed it could alter the equation of climate change with more attention being placed on solar influences which had been dismissed as minor.
The idea of a significant solar influence on climate change via cloud cover produced by cosmic rays has been proposed many times but it lacked conclusive experimental evidence as well as a detailed theoretical framework. Some have labelled the idea controversial with, at best, a weak effect.
The principle is that cosmic rays – high-energy particles that traverse the galaxy from supernovae – knock electrons out of air molecules. This produces ions – electrically positive and negative molecules in the atmosphere. The ions help aerosols – clusters of mainly sulphuric acid and water molecules – to form and become stable against evaporation – a process is called nucleation. The problem was that small aerosols need to grow nearly a million times in mass in order to have an effect on cloud formation. Until now, it was not known how this could happen.
The theory is that variations in the Sun’s magnetic activity alters the influx of cosmic rays reaching the Earth. When solar activity is low more cosmic rays reach the earth forming more low clouds, and the world is cooler. When the Sun is active fewer cosmic rays reach the Earth and, with fewer low clouds, the world warms.
Lead author Henrik Svensmark told the GWPF, “We have finally found the last piece of the puzzle of why cosmic rays make clouds. It was to prove that ions do in fact produce cloud condensation nuclei that are needed for making clouds. After four years of intense work we have cracked the problem and found the underlying mechanism.”
The new results reveal, both theoretically and experimentally, how interactions between ions and aerosols can accelerate the growth by adding material to the small aerosols and thereby help them survive to become cloud condensation nuclei.
Physical basis
According to Professor Svensmark it means that we now know why and how solar activity could be 5-7 times stronger than that estimated due to changes in the radiant output of the sun alone. It also explains why over geological times there has been much larger climate variations correlated with changes in cosmic rays. He adds that it also negates the idea that carbon dioxide has been controlling climate on these timescales.
“It provides a physical basis to the large body of empirical evidence showing that Solar activity plays a role in variations in Earth’s climate,” he says.
For example, the Medieval Warm Period around year 1000 AD and the cold period in the Little Ice Age between 1300-1900 AD fits with changes in solar activity. As does the recent so-called pause in global surface temperature this century which occurs at a time of remarkably low solar activity. Professor Svensmark believes it also explains climate changes observed during the 20th century, as well as coolings and warmings of around 2 degrees C that have occurred repeatedly over the past 10,000 years, as the Sun’s activity and the cosmic ray influx have varied. The are also much larger variations of up to 10 degrees C that occur as the Sun and Earth travel through the Galaxy visiting regions with varying numbers of exploding stars.
To achieve the results a theoretical description of the interactions between ions and aerosols was formulated along with an expression for the growth rate of the aerosols. This was subsequently confirmed experimentally in a large cloud chamber.
“Finally we have the last piece of the puzzle explaining how particles from space affect climate on Earth. It gives an understanding of how changes caused by Solar activity or by supernova activity can change climate,” says Henrik Svensmark.
Co-authors are senior researcher Martin Bødker Enghoff (DTU Space), Professor Nir Shaviv (Hebrew University of Jerusalem), and Jacob Svensmark, (University of Copenhagen).
Feedback: david.whitehouse@thegwpf.com
4) Sun May Be Dimming: NASA Launches New Probe To Confirm Declining Luminosity
International Business Times, 17 December 2017
Due to a drop in number of sunspots and the resulting decrease in total solar radiance (TSI) values, NASA launched a new sensor to study the dimming sun. Data from NASA’s Spaceweather website showed after a solar maximum 2012, which lasted till 2014, we have entered a solar minimum period in the solar cycle, which has caused the sun’s electromagnetic output to drop by 0.1 percent.
SpaceX launched a new sensor to the International Space Station named NASA's Total and Spectral Solar Irradiance Sensor (TSIS-1) on Dec. 15. It will add to the plethora of instruments dangling from the space station and help measure the TSI. It will also replace the aging SORCE spacecraft to aid in the study of the sun.
All past data showed we are heading towards the 11-year minimum in the sun’s cycle. In 2017, 96 days (27 percent) were without sunspots.
The TSI values last plunged to its low point in 2009. In fact, it marked the year with the lowest recorded electromagnetic activity from the sun, where 260 (71 percent) days of the 365 were spotless, since scientists started gathering data in 1978.
The Earth will reach peak spotlessness in 2018-2020. One thing that came to the attention of scientists since they started gathering TSI data is that the lowest point of every latest 11-year cycle, is lower than the lowest point of the previous cycle. The low in 2009 was the lowest since 1978 and if the 2020 readings are lower than the 2009 values, scientists from NASA can conclude our sun is dimming over time. […]
A 2013 NASA reports explained how this small change could affect the chemistry of Earth’s upper atmosphere and possibly alter regional weather patterns, especially in the Pacific.
It is already visible that as the magnetic activity of the sun decreases, influx of Galactic Cosmic Rays (GCR’s) increase. This has been observed by Helium balloon measurements over California.
The reason for this is that solar storm clouds, such as coronal mass ejections (CMEs), generally sweep aside incoming cosmic rays. During solar minimum, CMEs are very low and the effect of cosmic rays on Earth increases manifold.
Full story
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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