What characterizes an "inverse" gradient in train braking?

In the context of train braking, an "inverse" gradient refers to a situation where the pressure is higher at the rear of the train than at the front. This condition can occur due to various factors, such as a delay in the application of brakes at the front compared to the rear, or differences in brake system responses along the length of the train.

When there is higher pressure at the rear, it can lead to increased braking force in that area, which may cause a differential in how the train decelerates. This situation can have safety implications, as it might lead to the rear of the train braking harder than the front, potentially causing issues with train handling and stability. Understanding the behavior of braking systems, including pressure gradients, is crucial for ensuring safe train operations and effective braking performance.