Global warming facts challenged

Regarding “Don’t Ignore the Simple Facts,” a letter from Aaron Barnes (Sequim Gazette, July 9, page A-10):

The facts about global warming require some additional observations.

(1) “The mean global temperature has been rising since the start of the industrial revolution.” True, in fact global temperatures have been rising since the depths of the Little Ice Age late in the 17th century.

(2) “The cause of this increase is … “ The attribution of all warming after 1950 to CO2 is a theory, one which cannot explain previous warm periods like the Roman Warm Period or the Medieval Warm period or even the exceptional warmth of the 1930s. “ … The most important of these greenhouse gases is carbon dioxide … “  Not true, the most important greenhouse gas is water vapor.

(3) “The increase of carbon dioxide is due to human activity.” True, but not relevant.

(4) “Polar ice caps, arctic sea ice and mountain glaciers are rapidly melting.” Antarctic sea ice has been increasing for decades. This year it reached a new record. The Arctic ocean will not be ice-free this summer. Some mountain glaciers are retreating, some are advancing.

(5) “Global sea level is rising … “ True. It has been rising since the glaciers retreated about 11,000 years ago. The current rate is estimated at under 3 millimeters/year (one foot/century).

Another fact: There has been no global warming for the past 15 years.

And another: NOAA recently released its “gold standard” surface temperature data for the U.S. It shows a mild cooling trend for the contiguous 48 states for the past 10 years.

Ken Lutich

Sequim