Research on a diversity of natural disasters encompasses 5017 research units. There is research on storm surges to landslips, cold wave to heat wave, earthquakes to cyclones, dust storms to rain storms. A subtle difference and the experts are quick to qualify them with another name. Thus, debris slide, landslip, rock-fall, slope-failure can all be categorised under a landslide. An alteration in velocity and a cyclone transforms to a super cyclone; a change in magnitude and a moderate earthquake is labelled as an intense type; a modification in the intensity and heavy rainfall is termed as a cloudburst.

Some researchers use the geographical setting as a characteristic of the natural disasters. Thus, coastal disasters are considered different from those in the mountains. In certain units, the element of nature dictates the choice of some of the research units. There are water related, weather associated or geomorphology associated disasters. There are still other ways to sort the natural disasters among the 5017 research units.

There are researchers who have worked on the slow type of disasters like a drought, cold wave or heat wave while many others have worked on sudden and quick types like earthquakes, cyclones and tsunami. Using the feel of a natural disaster they could be grouped into the shaky, windy and the wet kind. Earthquake, cyclone and heavy rain respectively would fall into these three different types.