Figure — Various reconstructions of temperature over the last 1000-2000 years, relative to the reference period 1961-90. All reconstructions have been scaled to the annual, full Northern Hemisphere mean, over an overlapping period (1856-1980), using the NH instrumental record [Jones et al, 1999] for comparison, and have been smoothed on time scales of >40 years to highlight the long-term variations. The smoothed instrumental record (1856-2000) is also shown (from Mann et al., 2003).(source: Bradley, 2003)