As I write this second part of “What’s Happening to the Sun?”, the sun continues to be blank with no sunspots. We are still 3 to 4 years away from the solar minimum so the lack of sunspots for this long is a little unusual.
The sunspot cycle is like a pendulum, swinging back and forth every 11-years or so between times of high and low sunspot number. The next low is expected in 2019-2020. Given that the sun is the main driver of all weather and climate, the sinister-
sounding “blankness” has some experts predicting a “Maunder Minimum” phase similar to one which began in 1645 and which is referred to as the “Little Ice Age.”
The Maunder Minimum, named after solar astronomer Edward Maunder, was a period of few if any sunspots on the sun that lasted for a brutal 70 years and conditions were so cold, the Thames froze over. A slightly less intense ice age-like period called the Dalton Minimum — after British meteorologist John Dalton — arrived decades later and lasted from about 1790 to 1830. Since that time, sunspot and solar activity has increased. Overall average temperatures increased over the past century which lead many scientist to claim that global warming is primarily caused by man’s production of greenhouse gases. Still others say the warming is a natural cycle of climate change that occurs over hundreds of years.
It appears that man has affected the climate some, but probably not to the point that some global warming enthusiasts are claiming. But there was a time when the climate was as warm as or warmer than it is now. It was called the Medieval Warm Period. It was a time of warm climate in the North Atlantic region that may also have been related to other climate events around the world during that time, including China and other areas that lasted from about 950 to 1250. Despite uncertainties, especially for the period prior to 1600 for which data are scarce, the warmest period of the last 2,000 years prior to the 20th century very 
likely occurred between 950 and 1100. Records show peak warmth occurred at different times for different regions, indicating that the Medieval Warm Period was not a time of globally uniform change.
A study of radiocarbon-dated data from marine sediments in the Sargasso Sea found that the sea surface temperature there was approximately 1 °C (1.8 °F) cooler approximately 400 years ago (the Little Ice Age) and 1700 years ago, and approximately 1 °C warmer 1000 years ago (the Medieval Warm Period). Norse colonization of the Americas has been associated with warmer periods. Popular books say that Vikings took advantage of ice-free seas to colonize areas in Greenland and other outlying lands of the far north. 
Around 1000 AD the climate was sufficiently warm enough that there were vineyards in England and for the Vikings to journey to Newfoundland and establish a short-lived European outpost.
From around 985 AD Vikings founded the Eastern Settlement and Western Settlement, both near the southern tip of Greenland. In the colony's early stages they kept cattle, sheep, and goats, with around a quarter of their diet from seafood. After the climate became colder and stormier around 1250, their diet steadily shifted towards ocean sources; by around 1300 seal hunting provided over three quarters of their food. Warming can be the result of a number of factors, so that the cause of past climate change is not necessarily implicated in current climate change.
For instance, the Medieval Climatic Anomaly was characterized by relatively high solar activity, low volcanic activity and possible changes in ocean circulation patterns. These factors can explain both the scale and pattern of warmth at that time. It has been proven that Greenland was in fact greener than today. The Glaciers had receded (not disappeared) enough for the lowland areas to be fertile and climate temperate. The problem is that none of the historical facts are able to prove or disprove the claim that global warming is being caused mostly by man. As the sunspots continue to occur less frequently maybe we will find out which theory is accurate…global warming or global cooling. Feel free to leave comments and be sure to hit the “Like” button at the end of this post.