MYTH: Global Warming is Just Part of a Natural Cycle Since the Arctic has Warmed Up in the Past
FACT: The global warming we are experience is anything but natural! We are causing it through our day to day activities (i.e. burning fossil fuels like oil, coal and natural gas and cutting down forests) Scientists have proven these activities are pumping much more Carbon Dioxide into the atmosphere than was released in hundreds of thousands of years. This unwanted buildup of Carbon Dioxide is the biggest cause of global warming. This is nothing new - scientists in 1895 have been aware that Carbon Dioxide and other greenhouse gases trap heat, thusly warming the earth. And as the warming has increased over the decades - so has scientific scrutiny.
As far as previous Arctic warming is concerned, it's true that there were periods of warmth over the Arctic earlier in the 20th century. Data from that time period is limited but does reveal that the warmth didn't affect as many areas or persist from year to year as much as the present day warming trend. But that period - no matter how warm it was - does not pertain to the present day issues. That's because a brief trend doesn't discount a longer global event.