NCEP/NCAR matched to GISS, NOAA

In my previous post, I noted that comparing data on different anomaly bases brought in discrepancies because of vagaries of monthly averages over the base period. These are actually significant enough to detract from the use of the NCEP/NCAR index (base 1994-2013) in predicting GISS (1951-80) and NOAA (1961-90) indices.

So I have added to that table, below the NCEP monthly averages, recent monthly values adjusted to the earlier basis periods by adding the 1994-2013 month averages of GISS and NOAA anomalies. This expresses NCEP on those scales, although strictly, it is unique to those indices. Adding HADCRUT averages would give slightly different 1961-90 values.

I have also shown the actual GISS/NOAA values in the right column. The current tables are here:

GISS adj NCEP GISS Jun 0.835 NA May 0.773 0.71 Apr 0.702 0.71 Mar 0.855 0.84 Feb 0.818 0.82

NOAA adj NCEP NOAA Jun 0.618 NA May 0.558 NA Apr 0.461 0.469 Mar 0.573 0.564 Feb 0.545 0.575

Except for GISS May, the correspondence is very good.

Update. I calculated a whole lot more values, in a table below the fold. It looks as if the last few months aren't typical. The correspondence is still reasonable, but discrepancies as observed April-May are not unusual.

HadCRUT adj NCEP HadCRUT Jun 0.743 NA May 0.671 NA Apr 0.608 0.655 Mar 0.726 0.68 Feb 0.719 0.66 Jan 0.616 0.69 Dec 0.595 0.63 Nov 0.546 0.487 Oct 0.721 0.62 Sep 0.655 0.592 Aug 0.669 0.666 Jul 0.581 0.544 Jun 0.553 0.62 May 0.711 0.596 Apr 0.669 0.658 Mar 0.652 0.548 Feb 0.438 0.305

GISSlo adj NCEP GISSlo Jun 0.835 NA May 0.773 0.71 Apr 0.702 0.71 Mar 0.855 0.84 Feb 0.818 0.82 Jan 0.716 0.75 Dec 0.715 0.73 Nov 0.686 0.63 Oct 0.829 0.78 Sep 0.769 0.82 Aug 0.745 0.74 Jul 0.649 0.5 Jun 0.645 0.61 May 0.813 0.79 Apr 0.763 0.72 Mar 0.781 0.71 Feb 0.537 0.44

NOAAlo adj NCEP NOAAlo Jun 0.618 NA May 0.558 NA Apr 0.461 0.469 Mar 0.573 0.564 Feb 0.545 0.575 Jan 0.454 0.5 Dec 0.451 0.5 Nov 0.442 0.424 Oct 0.611 0.514 Sep 0.546 0.495 Aug 0.534 0.511 Jul 0.449 0.416 Jun 0.428 0.475 May 0.598 0.491 Apr 0.522 0.497 Mar 0.499 0.447 Feb 0.264 0.149

TempLSgrid adj NCEP TempLSgrid Jun 0.715 NA May 0.655 0.667 Apr 0.578 0.618 Mar 0.681 0.669 Feb 0.675 0.668 Jan 0.565 0.641 Dec 0.576 0.643 Nov 0.535 0.512 Oct 0.703 0.627 Sep 0.628 0.598 Aug 0.623 0.606 Jul 0.531 0.51 Jun 0.525 0.581 May 0.695 0.61 Apr 0.639 0.606 Mar 0.607 0.546 Feb 0.394 0.318

TempLSmesh adj NCEP TempLSmesh Jun 0.713 NA May 0.655 0.614 Apr 0.605 0.628 Mar 0.7 0.709 Feb 0.698 0.699 Jan 0.592 0.663 Dec 0.605 0.658 Nov 0.582 0.574 Oct 0.725 0.659 Sep 0.64 0.669 Aug 0.634 0.62 Jul 0.527 0.464 Jun 0.523 0.58 May 0.695 0.67 Apr 0.666 0.643 Mar 0.626 0.582 Feb 0.417 0.368