Natural Catastrophes

Our articles and data visualizations rely on work from many different people and organizations. When citing this entry, please also cite the underlying data sources. This entry can be cited as:

Hannah Ritchie and Max Roser (2018) - "Natural Catastrophes". Published online at OurWorldInData.org. Retrieved from: 'https://ourworldindata.org/natural-catastrophes' [Online Resource]

I. Empirical View

I.1 Number of reported disaster events

I.2 Deaths from disasters

Decadal deaths and death rates

In the following two charts we explore global fatalities from natural catastrophes since 1900. In the first chart we report the total annual number of deaths from natural catastrophes, as the decadal average from 1900. In the second chart, we report the same data but as the annual rate of global deaths (measured per 100,000 of the world population). The data for both charts can be found in the tables presented here.

Annual global number of deaths from natural catastrophes per decade, 1900-20151

Annual global death rate (per 100,000) per decade from natural catastrophes, 1900-20152

Annual number of deaths

Annual death rates

I.3 Other human impacts from disasters

Human impacts from natural disasters are not fully captured in mortality rates. Injury, homelessness, and displacement can all have a significant impact on populations.

The visualisation below shows the number of people displaced internally (i.e. within a given country) from natural disasters. Note that these figures report on the basis of new cases of displaced persons: if someone is forced to flee their home from natural disasters more than once in any given year, they will be recorded only once within these statistics.

Interactive charts on the following global impacts are available using the links below:

  • Injuries: number of people injured is defined as "People suffering from physical injuries, trauma or an illness requiring immediate medical assistance as a direct result of a disaster."
  • Homelessness: number of people homeless is defined as "Number of people whose house is destroyed or heavily damaged and therefore need shelter after an event."
  • Affected: number of people affected is defined as "People requiring immediate assistance during a period of emergency, i.e. requiring basic survival needs such as food, water, shelter, sanitation and immediate medical assistance."
  • Total number affected: total number of people affected is defined as "the sum of the injured, affected and left homeless after a disaster."

I.4 Economic costs

I.5 Death rates in the US

The following chart shows the declining death rate due to lightnings in the US.

In the first decade of the 20th century the average annual rate of death due to lightning was 4.5 per million in the US. In the first 15 years of the 21st century the death rate had declined to an average of 0.12 deaths per million. This is a 37-fold reduction in the likelihood of being killed by lightning in the US.

The following chart does not only show the death rate due to lightning, but the death rates due to 8 other weather events. None of these death rates shows a significant increase over time.

I.6 Earthquakes

Earthquake events

Earthquake events occur across the world every day. The US Geological Survey (USGS) tracks and reports global earthquakes, with (close to) real-time updates which you can find here.

However, the earthquakes which occur most frequently are often too small to cause significant damage (whether to human life, or in economic terms).

In the chart below we show the long history of known earthquakes classified by the National Geophysical Data Center (NGDC) of the NOAA as 'significant' earthquakes. Significant earthquakes are those which are large enough to cause notable damage. They must meet at least one of the following criteria: caused deaths, moderate damage ($1 million or more), magnitude 7.5 or greater, Modified Mercalli Intensity (MMI) X or greater, or generated a tsunami.

Available data — which you can explore in the chart below — extends back to 2150 BC. But we should be aware that most recent records will be much more complete than our long-run historic estimates. An increase in the number of recorded earthquakes doesn't necessarily mean this was the true trend over time. By clicking on a country in the map below, you can view it's full series of known significant earthquakes.

Deaths from earthquakes

Alongside estimates of the number of earthquake events, the National Geophysical Data Center (NGDC) of the NOAA also publish estimates of the number of deaths over this long-term series. In the chart below we see the estimated mortality numbers from 2000 BC through to 2017.

These figures can be found for specific countries using the "change country" function in the bottom-left of the chart, or by selecting the "map" on the bottom-right.

At the global level we see that earthquake deaths have been a persistent human risk through time.

I.7 Volcanoes

Significant volcanic eruptions

Deaths from volcanic eruptions

I.8 Landslides

Global landslide mortality risk distribution – SEDAC (NASA)3

Global Landslide Mortality Risk Distribution – SEDAC (NASA)0

I.9 Droughts

I.10 Hurricanes, Tornados, and Cyclones

North Atlantic Hurricanes

This site has a stunningly beautiful interactive world map that shows live wind patterns around the globe.

I.11 Extreme precipitation and flooding

Precipitation anomalies

Precipitation extremes

I.12 Extreme Temperature (Heat & Cold)

Olivier Deschenes and Enrico Moretti (2009)4 study the effect of extreme weather on life expectancy in the US. The authors find that "both extreme heat and cold result in immediate increases in mortality. The increase in mortality following extreme heat appears mostly driven by near-term displacement, while the increase in mortality following extreme cold is long lasting."

Heatwaves and high temperatures

Cold temperatures

I.13 Wildfires

US Wildfires

How are the frequency and extent of wildfires in the United States changing over time?

In the charts below we provide three overviews: the number of wildfires, the total acres burned, and the average acres burned per wildfire. This data is shown from 1983 onwards, when comparable data recording began.

Over the past 30-35 years we notice three general trends in the charts below (although there is significant year-to-year variability):

  • on average, the annual number of wildfires has not changed much;
  • on average, the total acres burned has increased from the 1980s and 1990s into the 21st century;
  • the combination of these two factors suggest that the average acres burned per wildfire has increased.

There has been significant media coverage of the long-run statistics of US wildfires reported by the National Interagency Fire Center (NIFC). The original statistics are available back to the year 1926. When we look at this long-term series (our chart is here) it suggests there has been a significant decline in acres burned over the past century. However, the NIFC explicitly state:

Prior to 1983, sources of these figures are not known, or cannot be confirmed, and were not derived from the current situation reporting process. As a result the figures prior to 1983 should not be compared to later data.

Representatives from the NIFC have again confirmed (see the Carbon Brief's coverage here) that these historic statistics are not comparable to those since 1983. The lack of reliable methods of measurement and reporting mean some historic statistics may in fact be double or triple-counted in national statistics.

This means we cannot compare the recent data below with old, historic records. But it also doesn't confirm that acres burned today are higher than the first half of the 20th century. Historically, fires were an often-used method of clearing land for agriculture, for example. It's not implausible to expect that wildfires of the past may have been larger than today but the available data is not reliable enough to confirm this.

I.14 Lightning

World map of frequency of lightning strikes – Wikipedia (NASA data)5

World Map of Frequency of lightning strikes – Wikipedia [NASA data]0

I.15 Famines

We cover famines in the Our World in Data entry on famines.

II. Correlates, Determinants & Consequences

Populations in less developed countries – countries with a lower Human Development Index – are more affected more by natural disasters. This is shown in the following table.

Disaster-related casualties and costs, median annual values by HDI group, 1971–1990 and 1991–20106

Screen Shot 2016-08-17 at 09.55.08

The clear link between poverty and a higher death rate due to environmental causes is also shown in the following scatterplot. The definition of environmental causes however is very wide in this case and includes deaths caused by indoor air pollution, sunburn, pollution, and other “environmental causes”.

Correlation between multidimensional poverty (MPI) and deaths due to environmental causes (per million people) – Human Development Report (2011)7

Correlation between Multidimensional Poverty (MPI) and Deaths due to environmental causes (per million people) – Human Development Report (2011)

Anderson, Robert, Johnson, and Koyama (2013)8 study the factors that caused the persecution of minorities in pre-modern Europe and find that negative income shocks – due to weather shocks – increased the probability of a persecution.

Similar results are documented in the literature on the effect of droughts on political systems and wars (through economic output shocks).9

III. Data Definitions & Metrics

III.1 Hurricanes, cyclones, typhoons & tornadoes

Hurricanes, cyclones & typhoons

There are multiple terms used to describe extreme weather events: hurricanes, typhoons, cyclones and tornadoes. What is the difference between these terms, and how are they defined?

The terms hurricanecyclone and typhoon all refer to the same thing; they can be used interchangeably. Hurricanes and typhoons are both described as the weather phenomenon 'tropical cyclone'. A tropical cyclone is a weather event which originates over tropical or subtropical waters and results in a rotating, organized system of clouds and thunderstorms. Its circulation patterns should be closed and low-level.

The choice of terminology is location-specific and depends on where the storm originates. The term hurricane is used to describe a tropical cyclone which originates in the North Atlantic, central North Pacific, and eastern North Pacific. When it originates in the Northwest Pacific, we call it typhoon. In the South Pacific and Indian Ocean the general term tropical cyclone is used.

In other words, the only difference between a hurricane and typhoon is where it occurs.

When does a storm become a hurricane?

The characteristics of a hurricane are described in detail at the NASA website.

A hurricane evolves from a tropical disturbance or storm based on a threshold of wind speed.

A tropical disturbance arises over warm ocean waters. It can grow into a tropical depression which is an area of rotating thunderstorms with winds up to 62 kilometres (38 miles) per hour. From there, a depression evolves into a tropical storm if its wind speed reaches 63 km/hr (39 mph).

Finally a hurricane is formed when a tropical storm reaches a wind speed of 119 km/hr (74 mph).

Difference between hurricanes and tornadoes

But, hurricanes/typhoons/cyclones are distinctly different from tornadoes.

Whilst hurricanes and tornadoes have a characteristic circulatory wind patterns, they are very different weather systems. The main difference between the systems is scale (tornadoes are small-scale circulatory systems; hurricanes are large-scale). These differences are highlighted in the table below:

Hurricanes/typhoonsTornadoes
Diameter60 to 1000s milesUp to 1 - 1.5 miles (usually less)
Wind speed74 to 157 mph40 to 300 mph
LifetimeLong (usually days)Very short (usually minutes)
Travel distanceLong (100s to 1000s of miles)Short distances
Environmental impactCan have impact on wider environment and atmospheric patterns.Local (although can be very high impact). Little wider impact on atmospheric systems or environment.

III.2 Volcanic Explosivity Index (VEI)

The intensity or size of volcanic eruptions are most commonly defined by a metric termed the 'volcanic explosivity index (VEI)'. The VEI is derived based on the erupted mass or deposit of an eruption. The scale for VEI was outlined by Newhall & Self (1982), but is now commonly adopted in geophysical reporting.10

The table below provides a summary (from the NOAA's National Geophysical Data Center) of the characteristics of eruptions of different VEI values. A 'Significant Volcanic Eruption' is often defined as an eruption with a VEI value of 6 or greater. Historic eruptions that were definitely explosive, but carry no other descriptive information are assigned a default VEI of 2.

Volcanic Explosivity Index (VEI)General descriptionCloud Column Height (km)Volume (m³)Qualititative DescriptionClassificationHow frequent?Example
0Non-explosive< 0.1 km1x10⁴GentleHawaiiandailyKilauea
1Small0.1 - 1 km1x10⁶EffusiveHaw/StromboliandailyStromboli
2Moderate1 - 5 km1x10⁷ExplosiveStrom/VulcanianweeklyGaleras, 1992
3Moderate-Large3 - 15 km1x10⁸ExplosiveVulcanianannuallyRuiz, 1985
4Large10 - 25 km1x10⁹ExplosiveVulc/Plinian10's of yearsGalunggung, 1982
5Very Large> 25 km1x10¹⁰CataclysmicPlinian100's of yearsSt. Helens, 1981
6> 25 km1x10¹¹ParoxysmalPlin/Ultra-Plinian100's of yearsKrakatau, 1883
7> 25 km1x10¹²ColossalUltra-Plinian1000's of yearsTambora, 1815
8> 25 km>1x10¹²ColossalUltra-Plinian10,000's of yearsYellowstone, 2 Ma

IV. Data Sources

Wikipedia has several lists of disasters, and an overview of these lists can be found at List of Disasters.

IV.1 Multiple Types of Disasters

EM-DAT – The International Disaster Database
  • Data: EM-DAT is a catalogue of disasters listing detailed information on natural catastrophes: droughts (famines), earthquakes, epidemics, extreme temperatures, floods, insect infestations, mass movement (dry & wet), storms, volcanos, and wildfires. There is also a data section on technological disasters.
  • Geographical coverage: Global – country and regional level (primarily cross-country data set, but also contains the name of the sub-national regions affected by disasters)
  • Time span: Since 1900
  • Available at: EM-DAT
  • Raw data has to be requested but the section on disaster trends encompasses a number of visualizations (time series and maps).

  • EM-DAT is maintained by the Center for Research on the Epidemiology of Disasters (CRED)

  • EM-DAT data on the annual number of deaths and number of affected by drought, epidemics, earthquakes, extreme temperature, flood, storm, tsunami, plane crash by country is available at Gapminder. Here is the data on the number of people killed in earthquakes during a year.

Earth Observatory by NASA – Natural Hazards
  • Data: Up to date information and satellite images on fires, storms, floods, volcanoes, earthquakes, and droughts
  • Geographical coverage: Global
  • Time span: Recent years – very up to date
  • Available at: earthobservatory.nasa.gov/NaturalHazards

Natural Hazards Data – U.S. National Oceanic and Atmospheric Administration's National Geophysical Data Center (NGDC)
  • Data: Data and maps on many natural hazards including cyclones, tsunamis, earthquakes, volcanoes, and wildfires. It includes the 'Global Significant Earthquake Database, 2150 B.C. to present' (5500 events) and 'The Significant Volcanic Eruption Database' and ‘Global Historical Tsunami Events and Runups’ among many other datasets.
  • Geographical coverage: Global – exact location
  • Time span: Millennia
  • Available at: Online here
  • Download maps as pdf or ArcIMS interactive maps, and data in tab-delimited data files or html.

Global Risk Data Platform
  • Data: Spatial data on tropical cyclones and related storm surges, drought, earthquakes, biomass fires, floods, landslides, tsunamis and volcanic eruptions.
  • Geographical coverage: Global
  • Time span: Recent past
  • Available at: The website can be found here.
  • Users can visualize, download or extract data on past hazardous events, human & economical hazard exposure and risk from natural hazards.

Socioeconomic Data and Applications Center (SEDAC) – by NASA

Center for Hazards & Risk Research at Columbia University
  • Data:
  • Hotspots: Risk levels calculated by combining hazard exposure with historical vulnerability for two indicators of elements at risk—gridded population and Gross Domestic Product (GDP) per unit area—for six major natural hazards: earthquakes, volcanoes, landslides, floods, drought, and cyclones
  • Natural disaster profiles: Profiles for 13 countries provide information on sub-national areas at risk from natural hazards including cyclones, droughts, earthquakes, volcanoes, floods, and landslides.
  • Geographical coverage: Global for hotspots data
  • Time span: Recent past
  • Available at: Online here


IV.2  Earthquakes

Global Earthquake Model (GEM)
  • Data: GEM Global Historical Earthquake Catalogue (1000-1900) and the ISC-GEM Global Instrumental Earthquake Catalogue (1900-2009)
  • Geographical coverage:Global
  • Time span: 1000 to today
  • Available at: Online here


IV.3 Fire

ATSR World Fire Atlas – by the European Space Agency (ESA)
  • Data: Monthly global fire maps
  • Geographical coverage: Global
  • Time span: 1995 to now
  • Available at: Online at the website of ESA here

  • An overview of alternative fire data can be found here at the FAO website.

IV.4 Tsunami

The Center for International Earth Science Information Network at the Earth Institute at Columbia University publishes data on the Population Affected by the Indian Ocean Tsunami (December 2004).

IV.5 Floods

Wikipedia has a List of Deadliest Floods and a List of Floods.

IV.6 Hurricanes

Unisys Data on Hurricanes
  • Data: Data on the track of the storm plus a text-based table of tracking information. The table includes position in latitude and longitude, maximum sustained winds in knots, and central pressure in millibars.
  • Geographical coverage: Atlantic, East Pacific, West Pacific, South Pacific, South Indian, and North Indian
  • Time span: 1851 until now
  • Available at: Online here
  •  This data set was used by Dean Yang (2008) – Coping with Disaster: The Impact of Hurricanes on International Financial Flows, 1970-2002. The B.E. Journal of Economic Analysis & Policy. Volume 8, Issue 1, ISSN (Online) 1935-1682, DOI: 10.2202/1935-1682.1903, June 2008. Online here.

National Climatic Data Center (NOAA)
  • Data: Data on the track of storms
  • Geographical coverage: Global
  • Time span: 1848 until now
  • Available at: Online at NOAA here

IV.7 Volcanoes

National Geophysical Data Center (NGDC)
  • Data:  Global listing of over 500 significant eruptions which includes information on the latitude, longitude, elevation, type of volcano, and last known eruption.
  • Geographical coverage: Global
  • Time span: 1750BC to 2017
  • Available at: Online at the Significant Volcanic Eruption Database.

Smithsonian Institution's Global Volcanism Program (GVP)
  • Data: Complete list of current and past activity for all volcanoes on the planet active during the last 10,000 years. Data includes eruption type, maximum Volcanic Explosivity Index, start and end dates (when known), and the type of evidence for the eruption.
  • Geographical coverage: Global
  • Time span: Past 10,000 years to present day
  • Available at: Online at the Volcanoes of the World Database
  • Full reference: Global Volcanism Program, 2013. Volcanoes of the World, v. 4.7.3. Venzke, E (ed.). Smithsonian Institution. https://doi.org/10.5479/si.GVP.VOTW4-2013

IV.8 Lightning

Lightning Maps
  • Data: Real-time tracking of lightning strikes
  • Geographical coverage: Global
  • Time span: Real-time
  • Available at: Online here