Tuesday, October 29, 2019

Myth: The Sun Causes Climate Change

Have you ever faced someone who believes that climate change is not real? We as scientists, tend to receive a boat load of criticism when trying to explain the truth about global warming and climate change. The truth is within this current short period of time, the Earth’s surface temperatures are climbing at a rapid rate that has not been seen before. In the 1980’s, when scientists first tried to explain why earth’s temperatures are rising so rapidly, they first turned to the sun. According to this website, scientists believed that an increase in surface temperatures on earth were due to a constant increase in sunspots. 

According to this article, scientists first turned to the sun due to it solar radiation influence on earth. Speculation increased in the mid 20th century following the discovery that the number of sunspots seen on the sun rose and fell in a regular 11 year cycle. This cycle, commonly known as the Schwabe cycle is caused by dark and light spots on the sun’s solar surface. These dark and light spots on the sun can affect the sun’s total irradiance that is received by earth; light spots naturally radiated more solar energy than dark. Naturally, scientists thought that the differences in solar radiation correlated with the variations in spots. Before the greenhouse effect was fully understood, scientists within the 19th century believed that rising global temperatures correlated to these light sun spots. 

Myth: This cycle is not causing global warming! The amplitude of the schwabe radiation cycle is too small and its timeline is too short to have a significant impact on the climate. According to this additional article, the trend between the solar irradiance and global temperatures do not correlate to one another. In order to understand what is happening, it is important to know about Earth’s natural greenhouse effect. When the sun’s solar energy strikes Earth's atmosphere, ⅓  of this radiation is reflected directly back out into space. The remaining ⅔ solar radiation is absorbed by Earth’s surface. Earth’s land and oceans take this absorbed radiation and reflect it back into the atmosphere where greenhouse gases are located. Greenhouse gases within the atmosphosphere trap this solar radiation from escaping into space, essentially trapping the heat and creating a sustainable surface temperature for all life on earth; this is natural budget system. This heat we feel on Earth's surface originates from the sun’s solar radiation 

So what is causing global temperatures to rise? Humans. The fact that we are experiencing the most rapid increase in global temperatures is because of humans. Increased human activities add greenhouse gases to the atmosphere through the use of burning fossil fuels, deforestation, and agriculture/land clearing. Increased greenhouse gases added to Earth’s atmosphere allow less solar radiation (heat) to escape into space. Due to increased greenhouse gases, there is more trapping of heat within our atmosphere which as a result raises Earth’s surface and oceanic temperatures.

-Elise Babula (7).


  1. I had no idea that scientists used to believe it was the sun causing global warming. I always through either people believed it was due to humans or they did not believe in it at all. It is too bad that humans have caused so much damage to the earth is such a short amount of time, especially within the last couple of decades. Did you come across any other theories that people may believe as to why the global temperature is rising or was it just that scientists originally thought it was due to the sun? Of course, we know exactly what is happening now but it would be interesting to know if there are any other weird theories out there.
    Posted by Brianna Luciani

    1. So scientists had two general ideas of thought when trying to uncover climate change. Scientists first thought that short wavelength radiation was effective enough to modify ozone concentrations in the level of atmosphere above where typical weather occurs. The second theory was that climate change was due to changes in solar activity and cosmic rays.
      -Elise Babula (7).

  2. This is very interesting as I was not aware of there being speculations that the sun itself was the reason for climate change. Even though climate change and global warming are becoming more aware of and prevalent, there still people who do not believe in them. Most people think of climate change as only the overall temperature rising, however, it is more than that. Climate change is also the reason behind the more extreme and unpredictable weather patterns that we have been seeing. For example as we have all experienced, sudden temperature drops, intense heat waves and many other climate events that were unstable.

    -Emily Wong

  3. In addition to severe weather patterns, climate change is also opening the door to new species-species interactions in such a way that ecosystems are changing their overall dynamics. For example, due to increased ocean temperatures, sea urchins off the coast of Australia are migrating up north into colder oceans. As a result major kelp bed forest ecosystems are becoming devoured by these introduced urchins, thus resulting in large biomass losses of kelp forest ecosystems.
    -Elise Babula (7).

  4. This theory actually lasted for a long time in the scientific community even after the introduction of the greenhouse effect. As always, when new discoveries are made, they need to be first proven and often it includes proven the previous way of thinking wrong. The idea that the sun is responsible for the heat increase is not unreasonable since the activities of the sun haven been recorded for centuries compared to the increase of CO2 or other greenhouses gases. It was an easy scapegoat and didn't require much explanations, where as the greenhouse effect is harder to understand (for some people) and actually points the fingers at us. Unfortunately, the scapegoating hasn't stop since and people still trying to push the blame on others then themselves.