BaCCC/Video Summaries/Natural Causes of Climate Change

Video Summary

Natural Causes of Climate Change (2:17)

https://www.youtube.com/watch?v=RRzbsnECsjM

• Serbian astronomer and physicist Milutin Milankovitch [or Milanković] identified three cycles he thought affected the Earth’s orbit and, therefore, the climate: eccentricity, axial tilt and precession.
• Eccentricity is the path of the Earth as it orbits around the sun.
• The current axial tilt is 23.5 degrees, but it fluctuates between 21.5 and 24.5 degrees, altering the climate in different regions of the planet.
• Precession is like a wobble that will go through a cycle every 26,000 years.
• Solar activity affects climate, especially the development of sunspots or what is known as the sunspot cycle.
• Volcanic eruptions can alter the Earth’s temperature, as volcanic gas and ash can block out the sun and reduce global temperatures.
• A volcanic winter occurs when sulfuric acid emanating from sulphur dioxide responds like microscopic mirrors, redirecting solar radiation and thus cooling the planet.
• We need to appreciate that there are indeed natural causes for shifts in our climate. However, are these enough to explain the dramatic changes we have been seeing across the planet for a number of years?