When using solar TSI as a reference for internal charging efficiency, the ENSO shifts, there are a lot of shorter term oscillation periods to contend with. Longer term the periods tend to blur making it difficult to isolate an exact lag period. This chart compares a variety of cumulative lag periods and I have "blurred" the 31.5 year period to show how it includes most of the other lag choices. The "blur" is about +/- 0.15 Wm-2/C degrees depending on the scaling used to compare with any particular temperature record or reconstruction. The different lags represent different charging efficiencies. If the ocean mixing efficiency is poor, the surface response is larger with a shorter period. If ocean mixing efficiency is good, the surface response is weaker and the oceans gain more energy.
Since the actual temperature data for the longer time frames is not very accurate relative to the "impact" trying to be determined, the blur provides a sanity check for the more devoted Cyclomaniacs.
The trailing cumulative lag averaging is just a cheat for comparing data sets. Most of the data is already averaged and seasonally adjusted to death so a proper integration of smoothed and seasonally adjusted data is most like mathturbation of the finest kind. A. M. Selvam among others have mentioned that cumulative impacts should be considered, my simply Cumulative Lags do just that. If they need to be fine tuned once more reliable data is available, then so be it.
Update: This chart uses the 31.5 year cumulative average plus I added the BEST volcanic forcing with BEST global and ERSSTv3b tropics and extratropics all spliced to the Oppo 2009 Indo-Pacific Warm Pool reconstruction.
From this Volcanic forcing can have a longer term impact requiring several decades to 100s of years for all of the regions to catch up. This used a 1980 to 2010 baseline and of course the uncertainty in the data increases moving back in time. Some anthropogenic forcing will likely be required once a reliable baseline "normal" can be determined.
No comments:
Post a Comment