The Volcano Hazard: Frequency and Distribution layer indicates the relative distribution and frequency of volcano hazard. The information displayed in Worldview/Global Imagery Browse Services (GIBS) shows that where there are higher grid cell values, there are higher frequencies of volcanic eruptions from 1979 to 2000: 1- 10, 11-30, 31-60, 61-130.
Global Volcano Hazard Frequency and Distribution is a 2.5 minute gridded data set based upon the National Geophysical Data Center (NGDC) Volcano Database spanning the period of 1979 through 2000. This database includes nearly 4,000 volcanic events categorized as moderate or above (values 2 through 8) according to the Volcano Explosivity Index (VEI). Most volcanoes are georeferenced to the nearest tenth or hundredth of a degree with a few to the nearest thousandth of a degree. To produce the final output, the frequency of a volcanic hazard is computed for each grid cell, with the data set consequently being classified into deciles (10 classes of approximately equal number of grid cells). The higher the grid cell value in the final output, the higher the relative frequency of hazard posed by volcanoes.
References: doi:10.7927/H4BR8Q45
The Volcano Hazard: Mortality Risk layer indicates the global volcano mortality risks and distribution from 1979 to 2000. The information displayed in Worldview/Global Imagery Browse Services (GIBS) reflects the decile within which the risk lies, ranging from low to high mortality risk: 1st to 10th decile.
Global Volcano Mortality Risks and Distribution is a 2.5 minute grid representing global volcano mortality risks. The data set was constructed using historical hazard-specific mortality loss data from the Emergency Events Database (EM-DAT) maintained by the Centre for Research on the Epidemiology of Disasters (CRED), subnational year 2000 population estimates from Gridded Population of the World, Version 3 (GPWv3), and volcano hazard data from the Global Volcano Hazard Frequency and Distribution data set. Estimates were made as to the mortality numbers associated with volcano hazard. In turn, these mortality estimates were classified into deciles, 10 classes of an approximately equal number of grid cells of increasing mortality risk.
References: doi:10.7927/H4736NT2
The Volcano Hazard: Economic Risk layer indicates the the proportional economic impacts of global volcano hazard from 1979 to 2000. The information displayed in Worldview/Global Imagery Browse Services (GIBS) reflects the decile within which the risk lies, ranging from low to high economic risk: 1st to 10th decile.
Global Volcano Proportional Economic Loss Risk Deciles is a 2.5 minute grid of volcano hazard economic loss as proportions of Gross Domestic Product (GDP) per analytical unit. Estimates of GDP at risk are based on regional economic loss rates derived from historical records of the Emergency Events Database (EM-DAT). Loss rates are weighted by the hazard's frequency and distribution. The vulnerability weights are based on historical economic losses in previous disasters. The economic loss risks are applied to GDP per unit area exposure to obtain economic loss risks. The weights are an aggregate index relative to losses within each region and country wealth class (classifications based on 2000 GDP) over the 20-year period from 1981 –2000. This index is then normalized by GDP. The methodology of Sachs et al. (2003) is followed to determine baseline estimates of GDP per grid cell. To better reflect the confidence surrounding the data and procedures, the range of proportionalities is classified into deciles, 10 classes of an approximately equal number of grid cells of increasing risk.
References: doi:10.7927/H43B5X3R