June 2010 could be a busy month for invasive plants, insects and animals seeking free rides to distant lands.

A new study forecasts climate factors such as temperature, humidity and rainfall will match at geographically distant airline departure and destination points then, which could help to shuffle invasive species, and the diseases they may carry, across the globe along existing flight routes.

The findings provide a framework that could help people who monitor airline flights - and the people, baggage and cargo aboard - to plan more efficiently and accurately for detecting and intercepting invasives.

Andy Tatem, who holds a joint position at the Emerging Pathogens Institute and the University of Florida’s (UF) geography department, said his model uses the latest forecast data for climate change and air traffic volumes.

"The problem is that as the global transport networks expand, we’re getting more and more invasive species and pathogens coming from different parts of the world that have survived isolated for thousands of years," said Tatem. "But now they have this high-speed link going between different regions of the world."

Tatem predicts a peak risk will be reached in June 2010, when multiple factors converge to create a month when the climate factors at many flight origin and destination airports would be most similar.

Tatem reached his conclusions by comparing fine-scale global climate models for 2009 and 2010 prepared by the Hadley Centre for Climate Prediction and Research with models forecasting traffic volumes on existing airline networks, prepared by OAG Worldwide.

The airline models include more than 35 million scheduled flights between 3,570 airports on more than 44,000 different routes, said a UF release.

"Some studies have shown that mosquitoes can fly on randomly, or they may get into baggage," he said. "But some things, like plant pathogens, happen when people purposely bring fruit aboard."