Natural Variability of SSTs has NOT been Accounted for by the US CCSP.
In my first post at jennifermarohasy.com/blog, I noted a magnificent 0.9 deg C drop and rebound in North Pacific SSTs (sea surface temperatures). The anomaly occurs there between the late 19th to the early 20th centuries. Its impact is reflected in global SST anomaly data illustrated on the same graph:
The largest of the late 19th century explosive volcanic eruptions, Krakatau in 1883, was approximately the same magnitude as Mount Pinatubo, and the Mount Pinatubo eruption did not duplicate the effect on SSTs. Assuming that TSI (total solar irradiance) variations are not responsible, and since there have been no discussions in any scientific papers that I could find of an anthropogenic cause for the drop in SST during that period, that leaves Thermohaline Circulation (THC) or Meridional Overturning Circulation (MOC) as the driver.
A similar but lesser drop in SST occurs in the North Atlantic. This data set is the basis for the much studied Atlantic Multidecadal Oscillation (AMO):
Referring to the first two illustrations, Global SST anomalies dropped 0.45 deg C from 1878 to 1910, then rebounded that amount plus 0.1 deg C from 1910 to 1941. I acknowledge that I cherry-picked the 1878 start date, but it’s used simply for illustration purposes. The AGW skeptical part of me looks at those graphs of Global SST anomalies and concludes that if a 0.45 decrease in SST is within the bounds of natural variability, a 0.45 deg C increase could also be natural, yet global SSTs haven’t come close to climbing 0.45 deg C above that 1878 starting temperature.
These THC/MOC oscillations are found in other SST data sets. The drop in SST during that period can also been seen in the data sets of THC upwelling points in both hemispheres of the Atlantic and Pacific Oceans:
The placid South Pacific appears at first glance to contain more subtle SST oscillations, and it’s easy to see the influence of the North Pacific. However, as illustrated, the eastern half of the South Pacific also contains substantial oscillations that are independent of the North:
If we divide the east-central mid-latitude South Pacific by 10 degree longitudinal bands and plot those data sets, those oscillations become much more pronounced:
THC/MOC MISSING FROM THE NEW CCSP REPORT
The effects of North Atlantic and North Pacific THC/MOC on global SST anomalies are illustrated in the preceding. In the recently released draft of “Global Climate Change Impacts in the United States”, the U.S. Climate Change Science Program briefly discusses the impacts of the El Nino-Southern Oscillation and the Pacific Decadal Oscillation on SALMON PRODUCTION. Salmon production? I believe they missed the greater effects of those two natural variables, their influences on climate. I searched the CCSP document for “Atlantic Multidecadal Oscillation “, for “thermohaline”, for “meridional”, for “overturning”, but the search feature of Adobe Reader returned the same message: “No matches were found.” I have to conclude from these oversights that the CCSP are either misinformed, or they have been misdirected, or they are attempting to mislead the public.
The graphs are from my series on Smith and Reynolds SST data:
Sea Surface Temperature Data is Smith and Reynolds Extended Reconstructed SST (ERSST.v2) available through the NOAA National Operational Model Archive & Distribution System (NOMADS):