Global warming advocates typically show only the last 150 years of the Earth’s temperatures, thereby deliberately misleading the public into thinking that the temperature change in the last 150 years is unusual, dangerous and is the result of carbon dioxide emissions. In actuality, the temperature changes in the last few years are neither unusual nor dangerous and are not primarily caused by carbon dioxide in the atmosphere.
Following is a chart of global temperature over the past 2,000 years:
How do we know that the charts above are accurate? There are numerous scientific methods of determining global temperatures going back to the time of the Vikings and before. The reasonable conclusions of those methods are reflected in the three charts above. There are also some interesting historical accounts that shed light on the climate change, however. For example, the book, Landnámabók, written in Iceland in the year 1125, records that one Thorkel Farserk, a cousin of Erik the Red who founded the colony, swam to fetch a sheep from the island of Hvalsey because he had no boat. The distance was over two miles. Because the normal water temperature at that location now at the warmest time of the year, in August, is 6o C, the story demonstrates that Iceland at that time had a much warmer climate than at present. [See “Determining the Climate.”]
I n a d d i t i o n t h e r e i s n o m e n t i o n o f s e a i c e a r o u n d G r e e n l a n d u n t i l t h e 1 2 t h c e n t u r y . B u t b e c a u s e o f a n i n c r e a s e i n d r i f t i c e a l o n g G r e e n l a n d ' s e a s t c o a s t b y t h e 1 2 t h c e n t u r y a n d later, the sailing route from Iceland to Greenland had to be changed. Ivar Bardsson, a Norwegian priest who lived in Greenland from 1341 to 1364, wrote: “From Snefelsness in Iceland, to Greenland, the shortest way: two days and three nights.Sailing due west. In…the sea there are reefs called Gunbiernershier. That was the old route, but now the ice