these partners will help us to identify events that have the potential to trigger displacement by issuing a humanitarian alert. Methodological challenges particular to displacement by disasters The 2017 GRID presents our latest findings on new displacement associated with disasters in 2016, and compares it with our historical dataset for 2008 to 2016. Taxonomic considerations To better understand the complexities of the phenomena, we plan to break disasters down into various stages and differentiating between their primary, secondary and subsequent triggers. The 2017 GRID dataset presents figures for displacement associated with sudden-onset hazards, but in future reports we intend to include that associated with slow-onset hazards such as drought. We developed a model-based methodology in 2014, which we used to monitor the displacement of pastoralists in the Horn of Africa during the 2010 to 2011 drought, and we started to collect data on slow-onset hazards in 2015 and continued to do so in 2016. Temporal coverage The 2017 GRID estimates are based on new displacement known to have taken place as a result of disasters for which natural hazards have been identified as the primary trigger. In part 1, we highlighted a number of displacement situations for which it is nearly impossible to identify a single cause or trigger. When available, we use the internationally acknowledged name of hazards and categorise them initially into four main types: geophysical, meteorological, hydrological and climatological. These are then refined into types, sub-types and sub-sub-types (see table A.8). Our dataset records incidents of displacement that occurred in 2016 and are supported by a reliable and comprehensive source. The main challenge we faced in collecting data for the year were overlapping events, such the floods and landslides that occurred in Peru and which we did not include in our estimates because the government provided only an aggregated figure for multiple separate displacements. We have similarly omitted aggregated figures provided by the government of China when we could not trace them back to a specific event. Table A.8: Taxonomy of natural hazards* Hazard category Type Sub-type Sub-sub-type Geophysical Ear thquakes, mass move ments, volcanic activity Ground shaking, tsunamis, sudden subsidence, sinkholes, landslides, rockfalls, ashfalls, lahars, pyroclastic flows, lava flows, toxic gases, glacial lake outburst flows (GLOF), volcanic eruptions Meteorological Sto r m s , e xtreme temperatures Extra-tropical storms, tropical storms including hurricanes and cyclones, convective storms, cold waves, heatwaves, severe winter conditions Hydrological Flooding, landslides, wave action Coastal floods, riverine floods, flash floods, ice jam floods, avalanches – snow, debris, mudflows, rockfalls – rogue waves, seiches Climatological Drought, wildfires Forest fires, land fires –bush, Fire whirls brush and pasture Derechos, hailstorms, thunderstorms, rainstorms, tornadoes, winter storms, dust storms, storm surges, haze, gales * This taxonomy is adapted from the classification system developed by the international disaster database (EM-DAT) maintained by the Centre for Research on the Epidemiology of Disasters (CRED) in Belgium. 106 GRID 2017