NASA - National Aeronautics and Space Administration

Buermann, W., B. Anderson, C. J. Tucker, R. E. Dickinson, W. Lucht, C. Potter, and R. B. Myneni (2003), Interannual covariability in Northern Hemisphere air temperatures and greenness associated with El Niño-southern oscillation and the Arctic oscillation, J. Geophys. Res., 108, D13, doi:10.1029/2002JD002630.