“No, you mustn’t say what it means!”

Climate Change: News and Comments

CERN chief forbids “interpretation” of CLOUD results

Although still very busy with other work, I keep looking out for results from the CLOUD experiment at CERN in Geneva, which is testing Henrik Svensmark’s hypothesis that cosmic rays help to make clouds. They are due for publication this summer. All I have just now is a startling remark by Rolf-Dieter Heuer, Director General of CERN, in an interview by Welt Online a few days ago.

Here is a tidied-up Google Translate version of the relevant exchange.

Welt Online: The results of the so-called CLOUD experiment, exploring the formation of clouds, are awaited with great excitement. Could these results still be important for understanding global climate change?
Heuer: This is indeed a matter of understanding better the formation of clouds. In nature there are many parameters at work – including temperature, humidity, impurities and also cosmic radiation. In the experiment, CLOUD investigates the influence of cosmic rays on cloud formation, using radiation [meaning particles] coming from the accelerator. And in an experimental chamber one can study, under controlled conditions, how the formation of droplets depends on the radiation and particulate matter. The results will be published shortly. I have asked the colleagues to present the results clearly, but not to interpret them. That would go immediately into the highly political arena of the climate change debate. One has to make clear that cosmic radiation is only one of many parameters.

Four quick inferences:

1) The results must be favourable for Svensmark or there would be no such anxiety about them.

2) CERN has joined a long line of lesser institutions obliged to remain politically correct about the man-made global warming hypothesis. It’s OK to enter “the highly political arena of the climate change debate” provided your results endorse man-made warming, but not if they support Svensmark’s heresy that the Sun alters the climate by influencing the cosmic ray influx and cloud formation.

3) The once illustrious CERN laboratory ceases to be a truly scientific institute when its Director General forbids its physicists and visiting experimenters to draw the obvious scientific conclusions from their results.

4) The resulting publication may be rather boring.

The interview with Welt Online (in German) is here:

http://www.welt.de/wissenschaft/article13488331/Wie-Illuminati-den-Cern-Forschern-geholfen-hat.html

For earlier posts on this blog about “waiting for CERN” see:

https://calderup.wordpress.com/2011/05/15/accelerator-results-on-cloud-nucleation/

https://calderup.wordpress.com/2011/05/17/accelerator-results-on-cloud-nucleation-2/

UPDATE 23 July:  see this Higgs story from the Institute of Physics. http://physicsworld.com/cws/article/news/46636

Yes, as we always knew, everyone is free to say what particle physics results at CERN seem to mean, even when they’re far from conclusive. If the Director General’s edict about CLOUD results were followed in this case, they’d have to say, “We must make clear that the Higgs boson is only one of many possible particles in the Universe so please don’t take these indications seriously.”

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Accelerator results on cloud nucleation (2)

Climate Change News and Comments

Did you get the message?

I’m not sure that the significance of my 15 May post, about the accelerator experiment in Aarhus, has been fully grasped. Following my 13 May post, the blogosphere seems to be still in a “waiting for CLOUD” mode. Yes, it will indeed be fascinating to see the first results from CERN’s CLOUD experiment in two or three months’ time, but meanwhile we have the results from Denmark. Perhaps I was negligent in not giving a little history.

The first laboratory test of the Svensmark hypothesis was the SKY experiment in Copenhagen, the outcome of which was published by the Royal Society of London in 2007. The positive results were of course politically incorrect, because Henrik Svensmark’s discovery of the effect of cosmic rays on clouds gave the Sun a much larger role in climate change than supporters of the man-made global warming hypothesis would like to admit.

The warmists were offered a delaying tactic by physicists who said, “Ah, but the SKY people used only natural cosmic rays and radioactive sources. Don’t believe them unless the CLOUD experiment in Geneva, simulating the cosmic rays with a fully controllable beam of accelerated particles, gets similar results.”

Conveniently for the warmists, CLOUD was very slow to get going. Meanwhile the Danes continued with their own experiments, including the one using an accelerator at Aarhus, as reported in Geophysical Research Letters a few days ago. The most important points are:

• The effect of cosmic rays in helping to seed cloud formation is verified with a particle accelerator, just as critics of SKY were demanding four years ago.
• A simple radioactive gamma-ray source gave just the same results in the Aarhus set-up so the earlier insistence, that only an accelerator experiment would do, was unwarranted.

Nevertheless, let’s say good luck to the CLOUD team. Their big chamber should be able to trace the growth of aerosol seeds much farther than in the small chamber used at Aarhus. And they have a large programme of future work, simulating atmospheric conditions at different altitudes.

See the Aarhus University press release that came out yesterday evening: http://science.au.dk/en/news-and-events/news-article/artikel/forskere-fra-au-og-dtu-viser-at-partikler-fra-rummet-skaber-skydaekke/

For references and other links, see my previous post: https://calderup.wordpress.com/2011/05/15/accelerator-results-on-cloud-nucleation/

For a video interview with Jasper Kirkby of CLOUD see: http://physicsworld.com/cws/article/multimedia/45950

Added 18 May: Ah, now the word is spreading. See

Anthony Watts: http://wattsupwiththat.com/2011/05/17/new-study-links-cosmic-rays-to-aerosolscloud-formation-via-solar-magnetic-activity-modulation/

David Whitehouse: http://thegwpf.org/the-observatory/3016-new-evidence-that-cosmic-rays-seed-clouds.html

The second item quotes me directly, and at the end of the second paragraph I should really have said ionizing “gamma rays” instead of “particles” — I amended it on this blog a few hours after posting it.

Added 20 May: Friendly words from The Scientific Alliance

http://us2.campaign-archive1.com/?u=f1e3eeb023e7d88eff0dda8a2&id=ed0b77bcc3&e=ac788faa66

Do clouds disappear? 3

Falsification tests of climate hypotheses

Cosmic rays and clouds at various latitudes

An exchange with Prof. Terry Sloan of Lancaster University

I’m promoting to the start of a new post a comment on an earlier post that came from Terry Sloan, together with my reply and his comment on my reply. I’ve included a graph that he sent in an e-mail because it wouldn’t upload into the Comments section.

After that, the discussion continues here with further remarks from me.

Sloan is one of the severest critics of the Svensmark hypothesis that cosmic rays influence the Earth’s low clouds. The earlier post, entitled “Do clouds disappear when cosmic rays get weaker?”, was concerned chiefly with whether or not sudden changes called Forbush decreases have observable effects on cloud cover. You can see that post in full here: https://calderup.wordpress.com/2010/05/03/do-clouds-disappear/

But the present interaction with Sloan mainly concerns a different question, about the influence of the Earth’s magnetic field. To help readers to get quickly up to speed, here’s the most relevant extract from my original post:

Aircraft seed clouds

Pick of the pics

Aircraft can seed precipitation from clouds

A hole left in a cloud-layer after an aircraft has passed through, provoking snowfall – or rainfall if the ice crystals melt on the way down to the ground. Photo: hole in altocumulus clouds over Mobile, Alabama, from 35 mm negative film, by Alan Sealls, chief meteorologist, WKRG-TV, Pensacola, Florida.

In 2007, meteorologists noticed a connection between snowfall near Denver, Colorado, and a turboprop aircraft descending through a cloud layer. The snowfall, in a band about 20 miles long and 2.5 miles wide, continued for about 45 minutes, resulting in about two inches of snow on the ground. They eventually figured out that when a turboprop plane flies through such a cloud layer with supercooled water droplets at about -15 degrees C, the tips of its propellers cause the air to expand, cool and freeze the droplets. Since then they have concluded that the expansion of air over a jet aircraft’s wings can have the same effect in colder conditions, -20 to -25C. Aircraft seeding may be particularly common in the northwestern USA and Western Europe.

Andrew Heymsfield, lead author of the report, is from National Center for Atmospheric Research (NCAR) in Boulder, Colorado.

References

Andrew Heymsfield et al., “Aircraft-Induced Hole Punch and Canal Clouds: Inadvertent Cloud Seeding”, Bulletin of the American Meteorological Society, June 2010

More info and a video here: http://www2.ucar.edu/news/mysterious-clouds-produced-when-aircraft-inadvertently-cause-rain-or-snow



Do clouds disappear?

Falsification tests of climate theories

Do clouds disappear when cosmic rays get weaker?

or “Don’t you worry, my dear, we’ve seen no tigers”

“The Sun makes fantastic natural experiments” Henrik Svensmark says, “that allow us to test our ideas about its effects on the Earth’s climate.” Most dramatic are the events called Forbush decreases. Ejections of gas from the Sun, carrying magnetic fields, can suddenly cut the influx of cosmic rays coming to the Earth from exploded stars.

According to the Svensmark hypothesis, cosmic rays seed the formation of low clouds, so there should be a reduction in the Earth’s low cloud cover in the aftermath of a Forbush decrease. During the past few years there have been repeated attempts to declare the hypothesis falsified, when various teams failed to find the expected decrease in the low cloud cover.

One morning in April 2008, I woke up to find that since midnight the BBC had spread all around the world the news that British physicists had more or less destroyed the Svensmark hypothesis. Violating a basic principle of objective reporting, the broadcasts went out before Svensmark himself had a chance to comment.

By lunchtime he and I had done our best to limit the damage – and the deception of the public – in brief radio and TV interviews. A remark from Svensmark went belatedly onto the BBC website, that the critic it quoted had “simply failed to understand how cosmic rays work on clouds”.

Two years later, critics still don’t understand it. But they go on telling the tale that Forbush decreases have no important effect on clouds, and the media go on echoing them. When Svensmark and his colleagues published in August 2009 a report that showed very clear effects, and explained why others had failed to see them, the BBC and almost everyone else ignored it. But not the scientific critics, who returned to the fray in December 2009 and February 2010.

Climate Change intro

CLIMATE CHANGE – Introduction

This section of Calder’s Updates is unavoidably a battleground, but within reason it will stick to the physics and dodge the propaganda that surrounds climate research.

Headings in this section

• News and Comments watching developments
• The Svensmark Hypothesis outlining the science
• Falsification Tests digging deeper into the physics
• Updating The Chilling Stars with evolving stories

In 1997 The Manic Sun by Nigel Calder was the first book to describe a new wonder of Nature – namely Henrik Svensmark’s discovery that the effect of cosmic rays on clouds amplifies the influence of the Sun on the Earth’s climate. Ten years of progress with the physics led to a second book The Chilling Stars in 2007, co-authored with Svensmark.I was also a script consultant to Mortensen Film for the TV programme about Svensmark’s work, “The Cloud Mystery”.

Despite plenty of time to re-consider the story, if it had turned out to be foolish, the evidence looks better and better as the years pass. Yet most climate scientists still ignore or reject Svensmark’s findings from observations of the real world, physics experiments, and theoretical analyses. Scoffing or vehement objections come from supporters of the man-made global warming hypothesis, who realise that the Svensmark hypothesis offers the strongest challenge to the assumptions in their climate models that predict climatic catastrophe.

The customary give-and-take arguments among experts, about which scientific theory fits the facts better, would be fair enough. But since climate physics became a political issue, the involvement of governments, funding agencies, scientific journals and the media in propagating a particular view of climate change has made rational debate difficult. Here’s a comment from Svensmark in an interview by Discover magazine, July 2007.

Question: In 1996, when you reported that changes in the Sun’s activity could explain most or all of the recent rise in Earth’s temperature, the chairman of the United Nations Intergovernmental Panel [on Climate Change] called your announcement “extremely naive and irresponsible”. How did you react?

Svensmark: I was just stunned. I remember being shocked by how many thought what I was doing was terrible. I couldn’t understand it because when you are a physicist, you are trained that when you find something that cannot be explained, something that doesn’t fit, that is what you are excited about. If there is a possibility that you might have an explanation, that is something that everybody thinks is what you should pursue. Here was exactly the opposite reaction. It was as though people were saying to me, “This is something that you should not have done.” That was very strange for me, and it has been more or less like that ever since.

To me (Calder) as a reporter of major discoveries that went on to win Nobel prizes in several different fields, the contrast between flimsy conjecture and creative brainpower backed by real evidence is fairly obvious. Being a generalist, rather than a specialist reporter of climate science, also helps to keep me objective, but I’m not inexperienced or ignorant in this field. It can be irritating when “warmist” journalists and campaigners with no relevant training of their own try to question my competence. Hey, I’ve even published a couple of formal scientific papers of my own.

Calder’s writing and editing on climate-related subjects

2007 (updated 2008) book: The Chilling Stars: A New Theory of Climate Change. Joint author with Henrik Svensmark

2003 book: Magic Universe: The Oxford Guide to Modern Science. Topics Include Biosphere from space, Carbon cycle, Climate change, Cosmic rays, Cryosphere, Earthshine, Earth system, El Niño, Ocean currents, Solar wind, and Volcanic explosions

1999 scientific paper: ‘The Carbon Dioxide Thermometer’, Energy & Environment, 1999, Vol. 10, pp. 1-18, on how CO₂ seems to respond to climate change rather than the other way around.

1997 book: The Manic Sun: Weather Theories Confounded about the Sun & climate, including Svensmark’s initial discovery about cosmic rays and clouds

1991 book and related TV series: Spaceship Earth about Earth observation, Including space observations of clouds, storms, temperatures, ice, oceans, bioproductivity, land use, and deforestation.

1990 book: Scientific Europe (editor, for Foundation Scientific Europe). It includes climate articles by Hermann Flohn, Bert Bolin, Paul Crutzen, and Lennart Bengtsson.

1983 book: Timescale: An Atlas of the Fourth Dimension. Among many other topics it traces climate change from the first ice ages 2300 million years ago to the Little Ice Age ending in 1850.

1974 book and related 2-hour TV programme: The Weather Machine. These included the first public reports of the confirmation of the Milankovitch ice-age hypothesis. Participants on TV include Hubert Lamb, Nicholas Shackleton, John Imbrie, Willi Dansgaard, George Kukla, Syukuro Manabe and Bert Bolin.

1974 scientific paper: ‘The Arithmetic of Ice Ages’, Nature, Vol. 252, pp. 216-18, with the first formal confirmation of the Milankovitch Effect. (Done with a pocket calculator, to legitimize what we were saying in The Weather Machine.)

1973 book: Nature in the Round: A Guide to Environmental Science (editor). Includes articles on climate change by L.P. Smith and Grahame Clark.

1968 book: Unless Peace Comes (editor). Includes Gordon MacDonald on weather and climate modification as weapons of war

1965 book: The World in 1984 (editor, for New Scientist). Among about 100 commissioned 20-yr forecasts, contributions on weather & climate came from Graham Sutton, Fred Singer, D.A. Davies & Roger Revelle

Calder has often spoken about climate change in lectures and on TV and radio, including an interview (2007) for The Great Global Warming Swindle, WagTV’s production for Channel 4. He has published articles on the subject since 1961.

About The Chilling Stars

About The Chilling Stars by Henrik Svensmark & Nigel Calder

“As Svensmark’s theory of cosmic rays, clouds, and climate penetrates a wide range of sciences, I suspect that specialists in various fields will profit from this plain-language introduction as much as general readers.” So ends the foreword to The Chilling Stars, written by Prof. Eugene Parker of Chicago, who also recalls how “eminent referees” opposed the publication of his own discovery of the solar wind, half a century earlier.

The Good Book Guide commented on The Chilling Stars: “If you are concerned by the doomsday scenarios regarding runaway climate change, then this alternative view of why the climate is warming will be of great interest.”

The Times of London described the book as “The new totem of the climate-change sceptics.”

Editions and translations

In English: UK etc. (Icon), Canada (Icon) and USA (Totem)

The Chilling Stars – A New Theory of Climate Change 2007

The Chilling Stars – A Cosmic View of Climate Change 2008 (with updating Postscript) illustrated above.

Danish translation Klima og Kosmos(Gads Forlag)

German translation Sterne Steuern Unser Klima(Patmos Verlag)

Dutch translation Kosmisch Klimaat(Veen Magazines)

Swedish translation De Kylande Stjärnorna (Anarchos Forlag)

Hebrew translation כוכבים קרירים(Am Oved)

Japanese translation    (Kouseisha)

Russian translation    Леденящие звезды. Новая теория глоб. изм. климата (Lomonosov)

Main contents of The Chilling Stars 2008 edition

Foreword by Eugene Parker vii

Overview 1

1 A lazy Sun launches iceberg armadas 11

2 Adventures of the cosmic rays 35

3 A shiny Earth is cool 63

4 Getting piggy over the stile 99

5 The dinosaurs’ guide to the Galaxy 132

6 Starbursts, tropical ice and life’s changing fortunes 156

7 Children of the supernovae? 180

8 The agenda for cosmoclimatology 204

9 Postscript 2008 – Carbon dioxide is feeble 231

Sources for individuals quoted 251

Scientific papers 257

Link to Icon Books UK, primary publisher http://www.iconbooks.co.uk/

Buy The Chilling Stars online

In English

UKAmazonhttp://www.amazon.co.uk/Chilling-Stars-New-Theory-Climate/dp/1840468661/ref=sr_1_1?ie=UTF8&s=books&qid=1203616546&sr=1-1

USA Amazonhttp://www.amazon.com/Chilling-Stars-2nd-Cosmic-Climate/dp/1840468661/ref=sr_1_2?ie=UTF8&s=books&qid=1203616818&sr=1-2

CanadaAmazonhttp://www.amazon.ca/Chilling-Stars-Henrik-Svensmark/dp/1840468661/ref=sr_1_2?ie=UTF8&s=books&qid=1203618178&sr=1-2

FranceAmazonhttp://www.amazon.fr/Chilling-Stars-Cosmic-Climate-Change/dp/1840468661/ref=sr_1_3?ie=UTF8&s=english-books&qid=1268234153&sr=8-3

GermanyAmazonhttp://www.amazon.de/Chilling-Stars-Theory-Climate-Change/dp/1840468661/ref=sr_1_1?ie=UTF8&s=books-intl-de&qid=1268233902&sr=8-1

JapanAmazonhttp://www.amazon.co.jp/Chilling-Stars-Cosmic-Climate-Change/dp/1840468661/ref=sr_1_3?ie=UTF8&s=english-books&qid=1268234523&sr=8-3

DenmarkSaxohttp://www.saxo.com/dk/item/henrik-svensmark-the-chilling-stars-paperback-2.aspx?searchkeyword=Svensmark&searchcategoryid=5197&searchurl=%2fsearch%2fsearch.aspx%3fkeyword%3dSvensmark%26categoryid%3d5197%26pagemodule%3dbooks

Norway Norlihttp://www.norli.no/SamboWeb/produkt.do?produktId=292248

SwedenBokiahttp://www.bokia.se/bok/9781840468663/the-chilling-stars-henrik-svensmark-nigel-calder/

In Danish

Denmark Saxohttp://www.saxo.com/dk/item/klima-og-kosmos-haeftet.aspx?searchkeyword=Svensmark&searchcategoryid=5197&searchurl=%2fsearch%2fsearch.aspx%3fkeyword%3dSvensmark%26categoryid%3d5197%26pagemodule%3dbooks

In German

Germany Amazonhttp://www.amazon.de/Sterne-steuern-unser-Klima-Erderw%C3%A4rmung/dp/3491360129

Austria Amazonhttp://www.amazon.de/gp/product/1840468661/ref=s9_simh_gw_p14_i3?pf_rd_m=A1IDDPBG1NC5TQ&pf_rd_s=center-1&pf_rd_r=0RWE0NH4KG39A2S5A031&pf_rd_t=101&pf_rd_p=463375193&pf_rd_i=301128

JapanAmazonhttp://www.amazon.co.jp/Sterne-steuern-Klima-Theorie-Erderwaermung/dp/3491360129/ref=sr_1_2?ie=UTF8&s=english-books&qid=1268234523&sr=8-2

In Dutch

NetherlandsVeen Magazineshttp://www.veenmagazines.nl/00/vm/nl/23/product/498/Kosmisch_klimaat.html

In Swedish

SwedenBokiahttp://www.bokia.se/bok/9789197705912/de-kylande-stjarnorna-svensmark-henrik-calder-nigel/

In Japanese

Japan Kouseisha (via Google Translate) http://translate.googleusercontent.com/translate_c?hl=en&prev=/search%3Fq%3Dkouseisha%26hl%3Den%26client%3Dfirefox-a%26sa%3DX%26rls%3Dorg.mozilla:en-GB:official%26nfpr%3D1%26biw%3D1059%26bih%3D498%26prmd%3Divns&rurl=translate.google.co.uk&sl=ja&u=http://www.kouseisha.com/01_astronomy/1213_2.html&usg=ALkJrhija4xDipDRbXrhF7VI5RnKs-8SbQ

In Russian

Russia Lomonsov http://www.lomonosov-books.ru/ledenyashie_zvezdy.html

USA Setbook http://www.setbook.org/books/1000489.html

About The Cloud Mystery

About The Cloud Mystery

Since 1998 the Danish film producer/director Lars Oxfeldt Mortensen has filmed the work of Henrik Svensmark and his team repeatedly, even when no programme was in production, to build up a remarkable historical record of discovery in progress. Svensmark has appeared in two resulting Mortensen TV programmes:

• The Climate Conflict, about the role of the Sun in climate change, 2001
• The Cloud Mystery, about the effect of cosmic rays on clouds and climatic history, 2008. (Nigel Calder was script consultant.)

Mortensen Film’s description of The Cloud Mystery

Svensmark views low clouds from a mountain in Tenerife

‘Our clouds take their orders from the stars,’ says the Danish scientist Henrik Svensmark. That’s the amazing and provocative discovery reported here. Most experts thought the idea was crazy.

The film records ten years of effort by the small team in Copenhagen that, in the end, solved the mystery of how the Galaxy and the Sun interfere in our everyday weather.

It’s provocative because Dr Svensmark’s revelations challenge the belief of most climate theorists that carbon dioxide has been the main driver of global warming. As a result he has faced never-ending opposition.

But strong support for the cosmic view of climate change comes from astronomer Nir Shaviv and geologist Jan Veizer. In the film they tell how the Galaxy has governed the Earth’s ever-changing climate over 500 million years.

The Cloud Mystery is aimed at a wide audience. Astonishing pictures from our Galaxy, the Sun, and cloud formations are mixed with spectacular animations to simplify the science. Comments by astronomers, geologists and climate experts convey their sense of adventure, and give scientific weight to the discoveries presented. The audience is taken on a trip around the world, where scientists from Denmark, Israel, Canada, the USA, and Norway contribute to this exciting story.

Linking all the discoveries is the non-stop rain of cosmic rays – energetic particles from exploded stars that battle with the Sun’s magnetic field to reach the Earth. Central in the story is an experiment in a Copenhagen basement. It showed how cosmic rays help to make chemical specks in the air on which water drops condense to make clouds.

The story concludes that clouds are the main driver of climate change on Earth.

The documentary follows Henrik Svensmark in his struggle to find the physical evidence of a celestial climate driver. The film demonstrates that science can be a rough place to be if you are in opposition to the established “truth”.

The Cloud Mystery (52-minutes) was co-produced with Arte France and has been distributed for broadcasting to eleven countries: Denmark, Norway, Sweden, Finland, France, Germany, Italy, Belgium, Spain, Israel and Iran. Efforts to place it with a UK broadcaster have been unsuccessful so far.

Latest broadcasts: 2 April 2010 Germany ARTE 21:45 France ARTE 22:05

Buy The Cloud Mystery DVD : http://thecloudmystery.com/The_Cloud_Mystery/Get_the_DVD.html

Preview clip http://thecloudmystery.com/The_Cloud_Mystery/Introduction.html

Some scenes in the film can be see on ClimateClips http://climateclips.com/

The Cloud Mystery website http://thecloudmystery.coml

Mortensen Film website, with contact details http://mortensenfilm.dk/

Mortensen’s ClimateClips http://climateclips.com/

Nutshell

The Svensmark hypothesis in a nutshell

Illustration from Svensmark, “The Adventurous Journey of Spaceship Earth” DTU Yearbook 2009

• Cosmic rays, high-energy particles raining down from exploded stars, knock electrons out of air molecules.
  
• The electrons help clusters of sulphuric acid and water molecules to form, which can grow into cloud condensation nuclei – seeds on which water droplets form to make clouds.
• 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 Sun became unusually active during the 20th Century and as a result “global warming” occurred.
• Recently (2006-2010) the Sun has been unusually lazy and “global warming” seems to have gone into reverse, as expected by the Svensmark hypothesis.
• Coolings and warmings of around 2 deg. C have occurred repeatedly over the past 10,000 years, as the Sun’s activity and the cosmic ray influx have varied.
• Over many millions of year, much larger variations of up to 10 deg. C occur as the Sun and Earth, travelling through the Galaxy, visit regions with more or fewer exploding stars.

For objections to the Svensmark hypothesis and answers to them, see Falsification tests

Nigel Calder

Sequence

The Svensmark hypothesis

Sequence of discoveries

The connection between cosmic rays and the cloud cover observed by satellites was announced at a space science meeting in 1996 and published in the following year (Henrik Svensmark & Eigil Friis-Christensen 1997). The report’s title called the discovery the “missing link” because it solved a big puzzle for climate researchers, as to how the Sun could exert an impact on climate that empirically exceeded by a wide margin the effect of variations in solar brightness measured by satellites.