CLIMATE CHANGE | New model shows transport’s impacts on human health, environment

CHICAGO, ILLINOIS — Researchers at the University of Illinois (UI) have developed a model that can predict through 2050 the impact of different environmental policies on human mortality rates and short- and long-term climate change caused by particular and greenhouse gas emissions.

According to an article posted on UI’s website Monday, the researchers used a “system of systems” approach to model how the increased volume of shipping, mode of transport, population density and environmental policies will factor into the future health and climate impacts of land freight.

The model can also identify which scenarios are the most harmful to the climate and which are most detrimental to human health.

The researchers found that enforcing truck fleet maintenance was an effective way to reduce particulate emissions, cutting the projected mortality rate by about one-third by 2050. The number of misfit, poorly maintained trucks on the road is uncertain, but that attention to overall performance is an important factor in maintaining health.

The researchers also examined the effect of changing population density in cities, and found that increasing urban compactness could reduce freight activity but increase human exposure to particulate pollution. This scenario offers a slight improvement in health benefits over the current urban sprawl trend.

There are still many scenarios to explore with the new model, including the effects of declining or improved infrastructure and increased traffic congestion. “Our model allows for a lot of flexibility, and this type of ‘system of systems’ approach should be routine when investigating policy change,” said Tami Bond, a civil and environmental engineering professor at UI.

“Environmental policy changes could push us toward cleaner, more efficient modes of land transport or more urban compactness, but we have to think ahead and start building up the infrastructure that supports those changes now,” she said.

A carbon tax, which places a value on greenhouse gases emitted, could entice shippers to switch to more efficient rail transport. The models indicate this could lead to a 24 percent reduction in greenhouse gas emissions over business as usual, the greatest reduction of all scenarios modeled.

The findings have been published in the journal Nature Sustainability.