Wednesday, June 10, 2015

TempLS May down slightly from April

GHCN Data was delayed slightly for May by the release of Version 3.3. When data became available, it was fairly complete. It showed a slight drop of 0.01°C from April (0.628 to 0.618). Satellite measures rose considerably.

Update 12 June. I'm still uncertain of this result. GHCN seems unsettled; according to my count, the most recent file has for May about 300 stations fewer than the day before.

This is at variance with the reanalysis data, which suggested a much warmer month. I wondered if V3.3 had an effect, but previous months were much as before. I'll watch the next few days for any changes, but as I said, most of the data is in. So May is looking more like April (cool for 2015) than February.

Details are in the report here. N Russia and Alaska had very warm spots; the poles were cool. The Arctic coolness was reflected in the reanalysis results. Generally the coolness was due to land; SST rose, as reflected by HADSST3.

There is an interesting Tech Note from NOAA on ver 3 here.


  1. RSS Land and HSST3 both went up in May, but RSS is always playing ketchup so it probably actually went up many weeks ago.

  2. I dont think May data from GHCNM can be trusted. It's not likely that it is so different compared to satellites, reanalyses and HadSST.
    I guess we will see a correction soon...