Global Warming Science: www.appinsys.com/GlobalWarming

Washington State - Puget Sound Climate: PDO Not CO2

[last update: 2019/05/10]

Temperature

The following graphs show the maximum temperature data by month for the entire temperature record 1895 to 2018/19. (Plots generated at https://www.ncdc.noaa.gov/cag/national/time-series/) 2019 had the third coldest February on record.

The following table shows the temperature trend by month (degrees per decade) since 1895 from the above graphs:

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
0.3	0.2	0.2	-0.1	0.0	0.0	0.0	0.2	0.2	0.0	0.1	0.0

(Without the one year of 1896, Nov would also be zero)

In more than 120 years of temperature data, there is almost no warming. Warming in Jan / Feb / Mar could not be due to CO2 since the water vapor levels are very high during the rainy season (see: http://appinsys.com/GlobalWarming/GW_Basics.htm).

Also keep in mind that due to the large variance in the data and lack of consistency of the trend within each, none of the trends are statistically significant from zero.

If we look at the last 30 years we see zero to negative trends for winter, spring and autumn, with some warming in summer (mostly caused by the single hotter year of 2015 – which was caused by a significant El Nino / PDO event.

Winter:

Spring:

Summer:

Autumn:

Pacific Decadal Oscillation

The following figure shows the annual maximum temperature for the complete record. The warmest year was 1958.

The following figure shows the Pacific Decadal Oscillation since 1900 (http://research.jisao.washington.edu/pdo/)

The following figure superimposes the annual maximum temperature data from above on the PDO. It is clear that Puget Sound temperatures are highly correlated to the PDO. CO2 just keeps increasing whereas the Puget Sound temperature follows the PDO almost exactly.

For more information on the PDO, see: http://appinsys.com/globalwarming/PDO.htm

Conclusion

The Puget Sound area insignificant warming is due to the PDO – not CO2.