Speaker
Ms
Atifa Syed
(Physics Department, York University)
Description
Reports of the Intergovernmental Panel on Climate Change have stated that precipitation has changed by up to 1% for each decade in the 20th century [1]. Indeed, the Clausius Clapeyron equation predicts absolute humidity increases by about 7% for each degree of warming assuming no change in the relative humidity. This study analyzed monthly precipitation observations recorded at over 1,000 stations located around the world. Each station had a minimum of 100 years of observations and the data at some stations extended into the 1700s. The data were first examined for inhomogeneieties that can arise due to changes in instruments and/or data taking procedure. The annual precipitation total was only found if all 12 monthly values had been recorded. For each station, the percentage precipitation change compared to the period 1961-1990 was found. These changes were then averaged over all stations of each continent. The data was also examined for effects of latitude, seasons and whether stations were in desert or wet areas. The results show no statistically significant change in precipitation from 1850 to the present.
1. Climate Change 2001: The Scientific Basis, Intergovernmental Panel on Climate Change
Primary authors
Ms
Atifa Syed
(Physics Department, York University)
Prof.
William van Wijngaarden
(Physics Dept., York University)
