Why are the public generally unaware of the important research that connects variations in the output of the Sun with climate change? They should know about it, since the Sun is responsible for far more climate change than anything we cause.
The reason for this ignorance is that the United Nations Intergovernmental Panel on Climate Change (IPCC), the source of most people's understanding about the field, was deliberately directed to study only the human causes of climate change. They did this because it narrowed their focus to just a few variables, particularly carbon dioxide (CO2). It came from industrialized nations and the objective was to shut them down. Show this by-product of industry was causing Earth-destroying global warming and you could justify shutting them down. The problem is you cannot identify the human-caused portion if you don't understand natural climate change - and we don't.
We have no control of the Sun, of course, so the IPCC pays no attention to sunspots, an important gauge of solar activity. In fact, the IPCC indicate they would not consider sunspots even if they did look at all causes.
Scientists have known about the apparent relationship between sunspot numbers and global temperatures for centuries. In Europe, it began in 1613 when Galileo, using the newly invented telescope, started recording these darker regions on the Sun. It caused a religious and social uproar because everything in the universe beyond the moon was supposed to be pristine and unblemished.
The first, most significant change to our understanding of sunspot patterns came in 1848 when, according to the National Oceanic and Atmospheric Administration, Swiss astronomer and mathematician Johann Wolf:
devised a daily method of estimating solar activity by counting the number of individual spots and groups of spots on the face of the sun. Wolf chose to compute his sunspot number by adding 10 times the number of groups to the total count of individual spots, because neither quantity alone completely captured the level of activity. Today, Wolf sunspot counts continue, since no other index of the sun's activity reaches into the past as far and as continuously.
The basic observation was that a high number of spots related to a warm Earth and fewer spots with cold. Until the 1990s, no plausible explanation for this relationship existed, so the IPCC was then justified to exclude the sunspot factor. However, in 1991, Friis-Christensen and Lassen published a fledgling theory, "Length of the Solar Cycle: An Indicator of Solar Activity Closely Associated with Climate." It was not the answer but framed the question. By 1996, Friis-Christensen and Svensmark published, "Variation of Cosmic Ray Flux and Global Cloud coverage – A Missing Link in Solar-Climate Relationships."
Again, the IPCC was wise not to accept the untested new theory. However, by 2000 the theory was evaluated empirically despite attempts to delay the evidence. What is now known as the Svensmark or Cosmic Theory has been thoroughly tested and confirmed and thus is no longer just a theory.
Here is how it works. Originating from outside the Solar System, galactic cosmic rays, high speed atomic nuclei or other particles traveling through space, continuously bombard the Earth. To reach us they must pass through, and are deflected by, the Sun's magnetic field. That field varies in strength, as evidenced by the changing sunspot numbers, and so the amount of cosmic radiation reaching the Earth also varies accordingly.
As the rays penetrate the Earth's atmosphere, they form particles in the lower atmosphere called condensation nuclei, which are particles around which water can form to create water droplets. These are the microscopic form of liquid water that is visible as clouds. It takes about a million of these particles to form a moderate-sized raindrop, so you get an idea of the density. That density reduces the amount of sunlight that can penetrate the cloud to heat the Earth's surface. The cloud is like a screen in a greenhouse controlling the temperature, so the variations in activity on the Sun visible as sunspots is cause and effect related to global temperature.
Tests were necessary to prove that the Cosmic Radiation did, in fact, generate condensation nuclei. Science writer Nigel Calder reported that the experimental proof for Svensmark's theory was delayed at the CERN facility in Switzerland where the experiments were conducted:
The Director General of CERN stirred controversy last month, by saying that the CLOUD team's report should be politically correct about climate change. The implication was that they should on no account endorse the Danish heresy – Henrik Svensmark's hypothesis that most of the global warming of the 20th Century can be explained by the reduction in cosmic rays due to livelier solar activity, resulting in less low cloud cover and warmer surface temperatures.
One of us, Tim Ball, published a paper relating the cloud cover theory to historical events using Little Ice Age art. The importance of this study is that we are currently approaching sunspot numbers associated with those in the Little Ice Age, which is why many of us are warning of global cooling. This contradicts the government and main stream media-created fake news of human-caused global warming, so naturally, these discoveries are hidden from public view to the extent possible. Through the Internet, however, the real story is slowly becoming more broadly known. It is about time.