Henrik Svensmark

Henrik Svensmark

Overview
Henrik Svensmark is a physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...

 at the Danish National Space Center
Danish National Space Center
The Danish National Space Center is a Danish sector research Institute and a part of the Danish Ministry of Science, Technology and Innovation. It is located in Copenhagen at Østerbro...

 in Copenhagen
Copenhagen
Copenhagen is the capital and largest city of Denmark, with an urban population of 1,199,224 and a metropolitan population of 1,930,260 . With the completion of the transnational Øresund Bridge in 2000, Copenhagen has become the centre of the increasingly integrating Øresund Region...

 who studies the effects of cosmic rays on cloud
Cloud
A cloud is a visible mass of liquid droplets or frozen crystals made of water and/or various chemicals suspended in the atmosphere above the surface of a planetary body. They are also known as aerosols. Clouds in Earth's atmosphere are studied in the cloud physics branch of meteorology...

 formation. His work presents hypotheses about solar
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...

 activity as an indirect cause of global warming
Global warming
Global warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...

; his research has suggested a possible link through the interaction of the solar wind
Solar wind
The solar wind is a stream of charged particles ejected from the upper atmosphere of the Sun. It mostly consists of electrons and protons with energies usually between 1.5 and 10 keV. The stream of particles varies in temperature and speed over time...

 and cosmic rays. His conclusions have been controversial as the prevailing scientific opinion on climate change
Scientific opinion on climate change
The predominant scientific opinion on climate change is that the Earth is in an ongoing phase of global warming primarily caused by an enhanced greenhouse effect due to the anthropogenic release of carbon dioxide and other greenhouse gases...

 considers solar activity unlikely to be a major contributor to recent warming, though it is thought to be the primary driver of many earlier changes in climate.

Henrik Svensmark is director of the Center for Sun-Climate Research at the Danish Space Research Institute
Danish Space Research Institute
Danish Space Research Institute was the space agency of Denmark from 1966 to 2005. It was a Danish sector research institute formed in 1966 under the Danish Ministry for Education and Research, later the Danish Ministry of Science Technology and Innovation...

 (DSRI), a part of the Danish National Space Center
Danish National Space Center
The Danish National Space Center is a Danish sector research Institute and a part of the Danish Ministry of Science, Technology and Innovation. It is located in Copenhagen at Østerbro...

.
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Encyclopedia
Henrik Svensmark is a physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...

 at the Danish National Space Center
Danish National Space Center
The Danish National Space Center is a Danish sector research Institute and a part of the Danish Ministry of Science, Technology and Innovation. It is located in Copenhagen at Østerbro...

 in Copenhagen
Copenhagen
Copenhagen is the capital and largest city of Denmark, with an urban population of 1,199,224 and a metropolitan population of 1,930,260 . With the completion of the transnational Øresund Bridge in 2000, Copenhagen has become the centre of the increasingly integrating Øresund Region...

 who studies the effects of cosmic rays on cloud
Cloud
A cloud is a visible mass of liquid droplets or frozen crystals made of water and/or various chemicals suspended in the atmosphere above the surface of a planetary body. They are also known as aerosols. Clouds in Earth's atmosphere are studied in the cloud physics branch of meteorology...

 formation. His work presents hypotheses about solar
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...

 activity as an indirect cause of global warming
Global warming
Global warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...

; his research has suggested a possible link through the interaction of the solar wind
Solar wind
The solar wind is a stream of charged particles ejected from the upper atmosphere of the Sun. It mostly consists of electrons and protons with energies usually between 1.5 and 10 keV. The stream of particles varies in temperature and speed over time...

 and cosmic rays. His conclusions have been controversial as the prevailing scientific opinion on climate change
Scientific opinion on climate change
The predominant scientific opinion on climate change is that the Earth is in an ongoing phase of global warming primarily caused by an enhanced greenhouse effect due to the anthropogenic release of carbon dioxide and other greenhouse gases...

 considers solar activity unlikely to be a major contributor to recent warming, though it is thought to be the primary driver of many earlier changes in climate.

Career


Henrik Svensmark is director of the Center for Sun-Climate Research at the Danish Space Research Institute
Danish Space Research Institute
Danish Space Research Institute was the space agency of Denmark from 1966 to 2005. It was a Danish sector research institute formed in 1966 under the Danish Ministry for Education and Research, later the Danish Ministry of Science Technology and Innovation...

 (DSRI), a part of the Danish National Space Center
Danish National Space Center
The Danish National Space Center is a Danish sector research Institute and a part of the Danish Ministry of Science, Technology and Innovation. It is located in Copenhagen at Østerbro...

. He previously headed the sun-climate group at DSRI. He held postdoctoral positions in physics at three other organizations: University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...

, Nordic Institute for Theoretical Physics, and the Niels Bohr Institute
Niels Bohr Institute
The Niels Bohr Institute is a research institute of the University of Copenhagen. The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics....

.

In 1997, Svensmark and Eigil Friis-Christensen
Eigil Friis-Christensen
Eigil Friis-Christensen is an expert in space physics, and Director of the Danish National Space Center.- Career :Friis-Christensen received a Magisterkonferens in Geophysics from University of Copenhagen in 1971. In 1972, he was a geophysicist at the Danish Meteorological Institute...

 popularised a theory that linked galactic cosmic rays and global climate change mediated primarily by variations in the intensity of the solar wind
Solar wind
The solar wind is a stream of charged particles ejected from the upper atmosphere of the Sun. It mostly consists of electrons and protons with energies usually between 1.5 and 10 keV. The stream of particles varies in temperature and speed over time...

, which they have termed cosmoclimatology. This theory had earlier been reviewed by Dickinson.
One of the small-scale processes related to this link was studied in a laboratory experiment performed at the Danish National Space Center (paper published in the Proceedings of the Royal Society A
Proceedings of the Royal Society
Proceedings of the Royal Society is the parent title of two scientific journals published by the Royal Society, whereas its initial journal, Philosophical Transactions, is now devoted to special thematic issues...

, February 8, 2007).

Svensmark's research downplays the significance to which atmospheric CO2
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...

 has affected recent global warming
Global warming
Global warming refers to the rising average temperature of Earth's atmosphere and oceans and its projected continuation. In the last 100 years, Earth's average surface temperature increased by about with about two thirds of the increase occurring over just the last three decades...

.

Cosmoclimatology theory of climate change


Svensmark detailed his theory of cosmoclimatology in a paper published in 2007.
The Center for Sun-Climate Research at the Danish National Space Institute "investigates the connection between solar activity and climatic changes on Earth".
Its homepage lists several publications earlier works related to cosmoclimatology.

Svensmark and Nigel Calder
Nigel Calder
Nigel Calder is a British science writer.Between 1956 and 1966, Calder wrote for the magazine New Scientist, serving as editor from 1962 until 1966...

 published a book The Chilling Stars: A New Theory of Climate Change (2007) describing the Cosmoclimatology theory that cosmic rays "have more effect on the climate than manmade CO2":
"During the last 100 years cosmic rays became scarcer because unusually vigorous action by the Sun batted away many of them. Fewer cosmic rays meant fewer clouds—and a warmer world."

A documentary film on Svensmark's theory, The Cloud Mystery
The Cloud Mystery
The Cloud Mystery is a documentary by Danish director Lars Oxfeldt Mortensen. It explores a controversed theory by Danish scientist Henrik Svensmark on how galactic cosmic rays and solar activity may affect cloud cover, and how this might influence global warming...

, was produced by Lars Oxfeldt Mortensen and premiered in January 2008 on Danish TV 2.

Experimental verification


Preliminary experimental verification has been conducted in the SKY Experiment at the Danish National Space Science Center. CERN
CERN
The European Organization for Nuclear Research , known as CERN , is an international organization whose purpose is to operate the world's largest particle physics laboratory, which is situated in the northwest suburbs of Geneva on the Franco–Swiss border...

, the European Organization for Nuclear Research in Geneva, is preparing comprehensive verification in the CLOUD
CLOUD
Cosmics Leaving Outdoor Droplets or the CLOUD is an experimental facility being run at CERN by Jasper Kirkby to investigate the microphysics between galactic cosmic rays and aerosols under controlled conditions...

 Project.

SKY Experiment


Svensmark conducted proof of concept experiments in the SKY Experiment at the Danish National Space Institute.
To investigate the role of cosmic rays in cloud formation low in the Earth's atmosphere, the SKY experiment used natural muons (heavy electrons) that can penetrate even to the basement of the National Space Institute in Copenhagen. The hypothesis, verified by the experiment, is that electrons released in the air by the passing muons promote the formation of molecular clusters that are building blocks for cloud condensation nuclei.

CLOUD Project Experiments


Scientists are preparing detailed atmospheric physics experiments to test Svensmark's thesis, building on the Danish findings. CERN started a multi-phase project in 2006, including rerunning the Danish experiment. CERN plans to use an accelerator rather than rely on natural cosmic rays. CERN's multinational project will give scientists a permanent facility where they can study the effects of both cosmic rays and charged particles in the Earth's atmosphere. CERN's project is named CLOUD (Cosmics Leaving OUtdoor Droplets). CERN posted a 2009 progress report on the CLOUD project.

On 25 August of 2011, the first result of the experiment were published.
They show that vapor traces, assumed until now to account for aerosol formation in the lower atmosphere can explain only a tiny fraction of the observed atmospheric aerosol production. The results also show that ionization from cosmic rays significantly enhances aerosol formation.

Galactic Cosmic Rays vs Global Temperature


An early (2003) critique of Svensmark's theory reanalyzed Svensmark's data and suggested that it does not support a correlation between cosmic rays and global temperature changes; it also disputes some of the theoretical bases for the theory. Svensmark replied to the paper, stating that "...nowhere in Peter Laut’s (PL) paper has he been able to explain, where physical data have been handled incorrectly, how the character of my papers are misleading, or where my work does not live up to scientific standards"

Mike Lockwood of the UK's
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

 Rutherford Appleton Laboratory
Rutherford Appleton Laboratory
The Rutherford Appleton Laboratory is one of the national scientific research laboratories in the UK operated by the Science and Technology Facilities Council . It is located on the Harwell Science and Innovation Campus at Chilton near Didcot in Oxfordshire, United Kingdom...

 and Claus Froehlich of the World Radiation Center in Switzerland published a paper in 2007 which concluded that the increase in mean global temperature observed since 1985 correlates so poorly with solar variability that no type of causal mechanism may be ascribed to it, although they accept that there is "considerable evidence" for solar influence on Earth's pre-industrial climate and to some degree also for climate changes in the first half of the 20th century.

Svensmark's coauthor Calder responded to the study in an interview with LondonBookReview.com, where he put forth the counterclaim that global temperature has not risen since 1999.

Later in 2007, Svensmark and Friis-Christensen brought out a Reply to Lockwood and Fröhlich which concludes that surface air temperature records used by Lockwood and Fröhlich apparently are a poor guide to Sun-driven physical processes, but tropospheric
Troposphere
The troposphere is the lowest portion of Earth's atmosphere. It contains approximately 80% of the atmosphere's mass and 99% of its water vapor and aerosols....

 air temperature records do show an impressive negative correlation between cosmic-ray flux and air temperatures up to 2006 if a warming trend, oceanic oscillations and volcanism are removed from the temperature data. They also point out that Lockwood and Fröhlich present their data by using running means of around 10 years, which creates the illusion of a continued temperature rise, whereas all unsmoothed data point to a flattening of the temperature, coincident with the present maxing out of the magnetic activity of the Sun, and which the continued rapid increase in CO2 concentrations seemingly has been unable to overrule.

Galactic Cosmic Rays vs Cloud Cover


In April 2008, Professor Terry Sloan of Lancaster University
Lancaster University
Lancaster University, officially The University of Lancaster, is a leading research-intensive British university in Lancaster, Lancashire, England. The university was established by Royal Charter in 1964 and initially based in St Leonard's Gate until moving to a purpose-built 300 acre campus at...

 published a paper in the journal Environmental Research Letters
Environmental Research Letters
Environmental Research Letters is an open-access electronic-only peer-reviewed scientific journal covering research in all aspects of environmental science. Numerical modelling or simulation, as well as theoretical and experimental approaches to environmental science form the core content...

titled "Testing the proposed causal link between cosmic rays and cloud cover", which found no significant link between cloud cover and cosmic ray intensity in the last 20 years. Svensmark responded by saying "Terry Sloan has simply failed to understand how cosmic rays work on clouds". Dr. Giles Harrison of Reading University, describes the work as important "as it provides an upper limit on the cosmic ray-cloud effect in global satellite cloud data". Harrison studied the effect of cosmic rays in the UK. He states: "Although the statistically significant non-linear cosmic ray effect is small, it will have a considerably larger aggregate effect on longer timescale (e.g. century) climate variations when day-to-day variability averages out". Brian H. Brown (2008) of Sheffield University further found a statistically significant (p<0.05) short term 3% association between Galactic Cosmic Rays (GCR) and low level clouds over 22 years with a 15 hour delay. Long-term changes in cloud cover (> 3 months)and GCR gave correlations of p=0.06.

External links