Three of the four methods of measuring global temperature show no signs of global warming:
- Proxy measurements (tree rings, sediments etc) for the past 1000 years
- Weather balloons (radiosondes) for the past 44 years
- Satellites (MSU Units) for the past 21 years.
The fourth method, surface measurement at weather stations, gives an averaged mean global rise of a mere 0.6°C over 140 years, but is intermittent and irregular. Individual records are highly variable, regional, and sometimes, particularly in remote areas, show no change, or even a fall in temperature.
It is concluded that temperature measurements carried out away from human influence show no evidence of global warming.
The small and irregular rise shown by many surface stations must therefore be caused by changes in their thermal environment over long periods of time, such as better heating, larger buildings, darkening of surfaces, sealing of roads, increases in vehicles and aircraft, increased shielding from the atmosphere and deterioration of painted surfaces.
Full Text of Policy Series No. 7 (PDF, 23 pgs, 799 Kb)