Canada did not make the list of countries with declining CO2 over 2005-2015 (although CO2eq did decline very slightly)

In part 2, I will look at long-term trends since 19th century. IPCC linear trend underestimates GMST change (rel to non-linear trend or decadal average). Preview shows multi-decadal trends for five operational (w/ Berkeley Earth added) compared to recent IPCC estimates. (6/6)

The combined effect of SST bias and coverage bias can be assessed by substituting the buoy SST series from @hausfath et al 2017 into C&W and HadCRUT4 leading to a new 2x2 matrix. www-users.york.ac.uk/~kdc3/p… … The combined trend in differences is -0.06 +/- 0.02 C per decade. (5/6)

Ship-buoy SST bias also plays a role: "NOAA adjust their data so as to remove an artificial drop in [SSTs] measured by ships since the early 2000s", but HadSST does not. (UK MetOffice metoffice.gov.uk/research/ne…). The combined effect can be seen in NASA GISTEMP vs HadCRUT4.

These comparisons show negative trend in differences over 1996-2018 (~0.035C per decade over last 20 years). A strong seasonal component in boreal winter (when Arctic warm anomalies usually peak) has recently emerged.

These 4 data sets form a 2x2 matrix wrt interpolation approach and underlying data sets. Coverage bias can be assessed by comparing series with polar interpolation to non-interpolated series with similar data i.e. Cowtan & Way vs HadCRUT4 and NASA GISTEMP vs NOAA GlobalTemp

@ClimateOfGavin @DekeArndt @rarohde @LabradorIce @hausfath @micefearboggis @past_is_future @KevinCowtan @climpeter @MichaelEMann Ongoing divergence of GMST series due to coverage bias & SST ship-buoy bias (~-0.06C per decade over 20 years) deepclimate.org/2019/02/22/2… (1/6)

The land analysis was apparently run earlier (Jan 12) than the HadSST3 kriging and subsequent merge. So wouldn't it be normal that they have different time stamps? Anyway here is a grid of the differences for 2018 - looks fine!

Late to the party, but I also project 2018 to be among the four warmest years in the NASA GISTEMP record. .@ClimateOfGavin @hausfather @rarohde

2017 surface temperature update deepclimate.org/2017/12/11/2…

.@hausfath @ClimateOfGavin 2017 on track to be 2nd or 3rd warmest year on record (and warmest La Nina year by far).