New study: 1.4°C of warming will trigger global rainfall disruption
Last updated on 5 March 2012, 6:13 pm
By RTCC Staff
Rainfall in wet season’s around the world will not be significantly affected by climate change until the world passes a threshold of 1.4°C of warming, a new study predicts.
The research used climate models to assess changes in rainfall at a regional rather than global scale, during rainy seasons.
The model’s performance was too poor during the dry season, when tested against observed measurements of rainfall from the past.
The ability to predict rainfall enables farmers to better plan what and when to plant. Large shifts in the timing and scale of rains can seriously reduce harvests and increase the threat of famine.
In order for changes in the rainfall induced by rising temperatures to be deemed significant, the relationship between the two must be stronger than the natural, short-term changes in rainfall.
The team from the National Oceanic and Atmospheric Administration (NOAA) in Boulder, Colorado, found that this “statistical significance” first occurs with 1.4°C of warming compared to the early 20th century.
According to the IPCC, the earth warmed by 0.6°C during the 20th century.
These changes would not be perceptible until 2040 at the earliest, according to the research.
Scientists have been unable to identify links between rising temperatures and rainfall on a small, localised scale.
Many observers have identified less predictability in rainfall, however, representing this with a mathematical formula in a climate model has proved elusive.
VIDEO: Michel Jarraud, Secretary-General, WMO talks to RTCC about the intricacies of climate science.