Beyond agriculture: A review of the Thornthwaite Moisture Index with respect to road pavements and other infrastructure applications

ABSTRACT

In 1948, the Thornthwaite Moisture Index was introduced as a new global climate classification system. Since its advent, the use of the index has moved beyond climate classification for agricultural systems. This review article identifies cases where the Thornthwaite Moisture Index has been applied in the design and maintenance of infrastructure, with an emphasis on its application in the transport arena. Furthermore, the article investigates the possible application of the Thornthwaite Moisture Index in providing an environmental indicator in the design of infrastructure to allow future adaptation to changing climate conditions. An adapted road degradation model for Australia is presented illustrating the effects on pavement degradation under changing climate conditions using the Thornthwaite Moisture Index.

KEYWORDS:

• Climate change
• infrastructure
• moisture index
• pavement

Notes

¹ A standard axle is a dual-wheeled (4-tire) axle transmitting a load of 80 kiloNewton (kN) on to the road pavement surface. Traffic load is thus measured as an equivalent number of standard axles passing over a road section. See Austroads (2008) for full details.