Climate sites

Institut Pierre-Simon Laplace
UCLA Department of Atmospheric Sciences
Lamont Doherty Earth Observatory
MétéoFrance

Statistics sites

Groupe "Climstat"
NCAR geophysical statistics project

Software

R
scilab
SSA-MTM Toolkit
Analyseries
python

Climate data

NCEP reanalyses
Climatic Research Unit instrumental data
ECA European intrumental data (temperature and precipitation)
Paleoclimate data: tree rings

Discussions

Realclimate.org