Illustrative: a block model of a city with water rising and falling through its streets, a heat island over its core, or the city growing

Risk Academy, led by the Nexus Consortium · Hazards, Disasters and Resilience · Department of Disaster Risk Reduction and Early Warning

Preventing new risk, reducing existing risk and managing residual risk under Sendai

Disaster risk reduction

Disaster risk reduction works on the three terms of risk at once: hazard, exposure and vulnerability, with capacity against them.

01Scope

What the discipline covers

The subtopics its courses and labs teach.

Courses
1 course open
Levels
L1 Introductory, L2 Intermediate
Labs
Exposure lab, Map lab, Network lab, Geo quiz, GeoAI lab
  • The Sendai Framework and its targets
  • Hazard, exposure, vulnerability and capacity
  • National and local DRR strategies
  • Risk-informed development
  • Disaster risk governance and mandates
  • Monitoring progress on DRR
  • Nature-based risk reduction
  • Prospective, corrective and compensatory risk management
02Maps

Build a twin of any place

Search any place or open the world; the layers and generators follow disaster risk reduction on the planet map, the globe and in 3D.

The Kahramanmaras earthquake sequence of 2023: a flat plan of the faculty twin. Terrain 59 to 3,044 m; 2 reference earthquakes, M7.5 to M7.8; 3,643,786 people in the box, 2020; Earthquakes M4.5 and above, past week: read live when the 3D twin opens; USGS ShakeMap intensity contours: read live when the 3D twin opens. Contours every 500 metres from the elevation grid; population count 2020, worldpop 1 km as four classes per cell (edges 11, 47, 405); reference earthquakes as marks.
The Kahramanmaras earthquake sequence of 2023, Turkiye. Flat plan of the same data: relief, the two epicentres with magnitude and depth, the WorldPop count grid and the numbers below. The 3D twin opens on devices that can draw it, once its data and code have been checked.
  • Terrain 59 to 3,044 m
  • 2 reference earthquakes, M7.5 to M7.8
  • 3,643,786 people in the box, 2020
  • Earthquakes M4.5 and above, past week: read live when the 3D twin opens
  • USGS ShakeMap intensity contours: read live when the 3D twin opens
Credits and dates per layer are listed under the stage. Relief in the twin is exaggerated ×1.5 for legibility.

Drag to move, right drag or Shift with a drag to turn and tilt, Ctrl with the wheel to zoom. Keyboard: arrows move, Shift with arrows turn and tilt, + and – zoom, 0 resets, V steps through the views, Escape clears.

Flat plan of the same data: relief, the two epicentres with magnitude and depth, the WorldPop count grid and the numbers below. The 3D twin opens on devices that can draw it, once its data and code have been checked.

The boundaries, names and designations shown do not imply any judgement on the legal status of any territory, or any endorsement or acceptance of such boundaries. Countries: Natural Earth (public domain).

03Live map

Hazards now in Türkiye

Flood water, active fires, heavy rain and smoke, beside where people live, over Türkiye.

The interactive map needs JavaScript; the layer list and sources are below.

Layers 3

Hazards now

Latest available

NASA GIBS / EOSDIS · ASTER GDEM (METI, NASA) · Blue Marble (NASA) · © OpenStreetMap contributors (ODbL) · Natural Earth

Loading the latest NASA imagery.

Drag to move. Ctrl or ⌘ and scroll, pinch or the buttons to zoom; hover for the values under the pointer; reset returns to the region.

Hazards now, framed on Türkiye.Satellite and model products as NASA publishes them, each with its own date. They are indicators, not assessments of any place.

Data: NASA GIBS · ASTER GDEM · Blue Marble · © OpenStreetMap contributors · Natural Earth · NASA EONET · U.S. Geological SurveySources and licences

  • We acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Science Data and Information System (ESDIS). Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • We acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Science Data and Information System (ESDIS). Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • VIIRS near-real-time products (flood, land surface temperature, snow cover, corrected reflectance), NASA LANCE; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • NASA Fire Information for Resource Management System (FIRMS), VIIRS 375 m active fire product, NASA LANCE; vector tiles via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • GPM IMERG precipitation, NASA Precipitation Processing System; distributed by the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC); imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • MODIS and VIIRS atmosphere products, NASA LANCE and LAADS DAAC; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • Center for International Earth Science Information Network (CIESIN), Columbia University. 2018. Gridded Population of the World, Version 4 (GPWv4): Population Density, Revision 11. NASA Socioeconomic Data and Applications Center (SEDAC). Licensed under CC BY 4.0. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). doi:10.7927/H49C6VHW. CC BY 4.0
  • ASTER GDEM is a product of METI and NASA (ASTER Global Digital Elevation Model V003, NASA LP DAAC); imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). Cite as: NASA/METI/AIST/Japan Spacesystems and U.S./Japan ASTER Science Team (2019). ASTER Global Digital Elevation Model V003. doi:10.5067/ASTER/ASTGTM.003. NASA open data
  • Made with Natural Earth. Free vector and raster map data @ naturalearthdata.com. Public domain
  • © OpenStreetMap contributors (ODbL), via NASA GIBS (coastlines, boundaries, roads and place names). Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). ODbL
  • Blue Marble, NASA Earth Observatory; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into H3 cells where shown (modified). NASA open data
  • Context on the globe and flat map: coastlines, boundaries, roads and place names from NASA GIBS reference layers (OpenStreetMap data, ODbL, © OpenStreetMap contributors); Blue Marble imagery as an optional base; 3D terrain and the elevation read-out from the ASTER GDEM elevation colour index (5 m to 200 m classes, exaggerated for legibility). Boundaries are drawn as published and imply no position on any territory.
  • Globe: MapLibre GL JS 6.9.1, BSD-3-Clause, © MapLibre contributors.
  • Live events: NASA Earth Observatory Natural Event Tracker (EONET); events are indicative and keep their original source links.
  • Live: NASA EONET Events are indicative, not authority warnings.
  • Live: U.S. Geological Survey Events are indicative, not authority warnings.
  • NASA GIBS: We acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Science Data and Information System (ESDIS).
  • River discharge forecast, 30 days with range (GloFAS via Open-Meteo): Contains modified Copernicus Emergency Management Service information 2026; not a flood warning.
  • Weather data by Open-Meteo.com (https://open-meteo.com/), licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/).
  • Optional layers (20 sources in the layer list: live, forecast, observed and context) print their provider credit on the map and here when switched on; forecasts are model output and derived indices are estimates.

Layers and dates

  • Flood water, 3-day composite: VIIRS Global Flood Product, NASA LANCE · 14 Oct 2026
  • Active fires and thermal anomalies: VIIRS NOAA-20 375 m (FIRMS), NASA LANCE FIRMS · 13 Oct 2026
  • Precipitation rate, daily mean: GPM IMERG, NASA GES DISC · 12 Oct 2026
  • Aerosol optical depth, daily: VIIRS NOAA-20 Deep Blue AOD, NASA LANCE · 13 Oct 2026
  • Population density, 2020: Population: CIESIN, Columbia University, Gridded Population of the World v4.11 (2018), NASA SEDAC, CC BY 4.0 · static

04The subject

The subject, methods and measures and debates and bodies

The field and its scope

For planners, risk governance officers, development practitioners and analysts who need to turn hazard, exposure and vulnerability information into strategies that prevent new risk and reduce the risk that exists.

05The method

From a loss curve to a benefit-cost ratio: how average annual loss, a discount rate and an investment decide whether risk reduction pays

A loss exceedance curve gives the loss at every return period; its integral is the average annual loss; a risk reduction measure lowers the curve; the avoided loss, discounted over the measure's life, against its cost gives the benefit-cost ratio a finance ministry asks for.

Sources: Shreve and Kelman, Does mitigation save? Reviewing cost-benefit analyses of disaster risk reduction (2014); Mechler, Reviewing estimates of the economic efficiency of disaster risk management (2016); Hallegatte, Vogt-Schilb, Bangalore and Rozenberg, Unbreakable: Building the Resilience of the Poor in the Face of Natural Disasters (2017); United Nations, Sendai Framework for Disaster Risk Reduction 2015–2030 (2015).

06At a glance

At a glance, with 5 related topics

Disaster risk reduction at a glance

risksacademy.comhazards-resiliencediscipline

Disaster risk reduction: 1 primary courses open, 2 in preparation and 4 also taught here, across 8 subtopics and 3 connected disciplines. Courses: RAF-101 L1 open, RAF-119 L1 in preparation, RAT-232 L2 in preparation, RAF-102 L1 also taught here, RAN-307 L2 also taught here, RAN-317 L2 also taught here, RAN-339 L3 also taught here.
Disaster risk reduction at a glance
  • Open, 1
  • In preparation, 2
  • Also taught here, 4
  • Subtopics, 8
Course codes from the curriculum; study levels L1 to L4.
Twin builderBuild a twin of any placeWorked example: the Kahramanmaras earthquake sequence of 2023 · 5 generators · 13 layers · 3 instruments
07Labs

How the subject is practised in labs

08Console

How Disaster risk reduction is taught, as a process you can run

Press Play to run this process from this page's own data.

09Practice

Practice, learning and connections

How technology helps and what risk it brings

10Take part

Take part in Hazards, Disasters and Resilience

Start from who you are.

11References

Core references and where to begin

Start with Wisner, then United Nations, then Lavell.

12Questions

Questions, answers and key terms

Is study here free?
Yes. Every course and learning material of Risk Academy, led by the Nexus Consortium, is free to study, self-paced or with a cohort. Ordinary participation has no fee; paid work, internships and fellowships are separate arrangements.
What does completing a course give me?
A completion record: the course, its version, the date and what was assessed, private by default and shared by you. It stacks into discipline, department and programme achievements. A record states what was studied and assessed and does not certify competence; it is not a licence, a professional title or an employment status.
Where do the data and the places come from?
Every faculty teaches on a twin of a real place built from open data; each layer carries its provider, licence and date, and every result on the Academy states its source. Maps and figures are indicators for teaching, never an assessment of a place.
How do I take part beyond the courses in disaster risk reduction?
Form a competence cell of three to seven people, study a shared pathway, take a supervised assignment in the National Working Groups, or bring a cohort from your institution. For organisations.

Key terms

Term

Disaster risk

The potential loss of life, injury or damaged assets in a period, as a function of hazard, exposure, vulnerability and capacity.

Term

Vulnerability

The conditions that increase the susceptibility of people, assets or systems to the impacts of hazards.

Term

Capacity

The strengths and resources available to manage and reduce disaster risk and strengthen resilience.

Term

Residual risk

The disaster risk that remains even when effective risk reduction measures are in place.

ReportsContribute

Contribute evidence from this page.

Reports is the Consortium's quarterly publication. What you know about this subject can become evidence, a case or a correction in the next edition, credited to you and published under CC BY 4.0 where it is your own work.

Risk Academy
Disaster risk reduction

Start with an open course

The catalogue lists each course with its outcomes, labs, hours and level.

Risk Academy

Courses · practice · credentials

Not for profit

Our articles, maps and twins are free to read and free to republish. Readers and partners keep it that way.

Partner with us

Who funds us

Risk Academy is a not-for-profit institution. To ask who funds a piece of work, use the funding questions form.

Independence

Editors and the expert reviewers named on each article decide what we publish. Funders and partners do not review or approve articles before publication.

Licence

Articles: CC BY 4.0. Figures, maps, twins and data: CC BY 4.0. Other uses: ask through the permissions form.