Confluence

A confluence is an intense concentration of amati, formed as the result of fluctuations of natural amati. Minor ebbs and flows in amati occur naturally, at near-undetectable levels. When these fluctuations interact, they can compound in a process similar to resonance or rogue waves, causing a rapid increase of amati in a localized area. Confluences vary widely in size, intensity, duration, and impact. Due to the difficulty in precisely measuring the level of natural amati in a given area, the distinction between a confluence and a local high can be difficult to delineate, and there are competing definitions. One simplified definition is that a confluence is a concentration of amati more than twice as strong that of the surrounding area, when controlled for the presence of any living beings (which will always have a high level of amati).

Parameters
Contrary to common belief, small confluences occur frequently, virtually everywhere. Small-scale confluences are only inches across and last mere seconds, with no more impact on the world than any other natural amati. They are not typically noticeable and are difficult to distinguish from a dalar's own amati.

Larger confluences, of the kind perceptible by an average dalar, are less common. These types of confluences can affect a larger area (up to a few feet) for a longer period of time (up to several minutes) with more notable results. Common effects can include physical and mental impacts, such as a headache or emotional change in a nearby living creature, moving a physical object, creating a small temporary enclave, or causing a brief occurrence of prescience.

The most intense of "ordinary" confluences can last up to an hour and cause permanent changes, such as alteration to the intelligence or growth pattern of an affected living creature or moving large physical objects.

Research
Confluences are difficult, if not impossible, to consistently predict, due to the difficulty of observing and recording the fluctuations that underlie them. Prescience can offer advance notice, but due to how rapidly confluences build up and dissipate, this isn't hugely useful.

One major obstacle to studying confluences is that, being formed through alterations in local amati, they are impacted by any nearby concentrations of amati, such as a dalar observer. (or, in truth, even humans, animals, or large amounts of biomass). Mechanical methods of amati observation also have the possibility of affecting the natural flow of amati in an area. As a result, researchers are left with the undeniable truth that confluences exist... and the undeniable truth that they can't objectively observe them.

That being said, researchers generally accept (large) confluences are more common in areas with naturally high amati levels (such as a forest), yet, ironically, less common in heavily-populated areas, where the ebb and flow of natural amati is disrupted so frequently by the movement of dalar or humans that it never builds into large confluences.

Amati storms
Amati storms are particularly intense forms of confluences. Remarkably rare--perhaps occurring only once a century--amati storms are caused when confluences themselves interact, triggering a sort of "super-confluence". They are on a scale apart from even the largest "normal" confluences, affecting hundreds of square feet, perhaps even miles, potentially for hours, with dramatic effects. Due to their rarity, there are no known credible observations by living dalar, meaning much of their details are speculation based on scaling up from ordinary confluences and information gleaned from historical records and myths.

An amati storm is theorized to have created the first dalar by altering their mental structure to allow them to perceive (and thus consciously interact with) amati. As such an incident would have impacted hundreds of individuals in a large area, it gives some idea of the potential scale of such a storm.