The Weather and Networked Data (WAND) system is a collaborative effort between the Grains Research and Development Corporation (GRDC), the Cotton Research and Development Corporation (CRDC), and commercial partner Goanna Ag. Designed to assist growers, WAND provides real-time information and a two-hour nowcast of hazardous surface temperature inversions. By measuring various weather parameters, WAND detects these inversions, which are critical for determining optimal spray times. The technology, developed over six years, offers a much-needed solution for primary producers across Australia and beyond. A network of 100 WAND towers and counting spans grain and cotton growing regions in central and southern Queensland and New South Wales.

Why WAND is Needed:

The off-target movement of herbicides and pesticides, commonly known as spray drift, poses a significant challenge in mixed-cropping regions. These areas often see the simultaneous application of various chemicals. Research has revealed that unsuitable spraying conditions not only cause unintended damage to non-target crops but also result in up to 50% of applied pesticides missing their intended target.

Benefits of Using WAND:

WAND eliminates guesswork by offering real-time data to guide spraying decisions. By monitoring hazardous surface temperature inversions, it helps determine optimal spray times. This clarity enhances precision and reduces the risk of spray drift.

Understanding Inversions:

Surface temperature inversions occur when air temperature increases with height, creating a layer of cool, dense air trapped beneath warmer air near the ground. These inversions typically occur from an hour before dusk to an hour after sunrise. However, identifying hazardous inversions requires knowledge of their presence and understanding wind flow conditions and turbulence levels within the inversion layer.

Hazards of Inversions:

An inversion becomes hazardous when insufficient turbulence prevents spray droplets from settling. Instead, laminar winds—smooth and streamlined—transport these suspended droplets over long distances. Unlike turbulent conditions that allow droplets to reach their intended targets, laminar winds contribute to widespread damaging spray drift. When a hazardous inversion forms, it acts as a barrier, isolating the inversion layer from normal weather conditions and wind patterns.

The free network is available to all growers and spray applicators and can be accessed via a web browser on smartphones, tablets and computers. To access WAND, visit the website.