Illustrative: a state in a double-well potential, tipping and returning with hysteresis as the forcing changes
Risk Academy, led by the Nexus Consortium · Systems and Nexus Studies · Department of Systemic Risk and Complexity
Extreme pandemics, nuclear risk, space weather, large eruptions and advanced technology
مەترسییە کارەساتبارە جیهانییەکان
Global catastrophic risks covers low-probability, high-impact risks that could severely harm humanity at global scale: extreme pandemics,nuclear war, extremespace weather and near-Earth objects, very large volcanic eruptions, severe climate outcomes and risks from advanced technology, and how such risks can be studied and governed with honesty aboutdeep uncertainty.
The Tonle Sap and the Lower Mekong at Phnom Penh, Cambodia.Flat plan of the same data: the lake and rivers, the dams, the plants by capacity, the cropland and tree cover cells and the numbers below. The 3D twin opens on devices that can draw it, once its data and code have been checked; discharge, vegetation, surface water and the annual land cover load in the twin on request, each with its data date.
Terrain 0 to 1,700 m
River 2,956 km
14 dams
6 power plants, 88 MW
Tree cover 37.8 percent of the box
Cropland 39.9 percent of the box
Built-up 0.9 percent of the box
Permanent water 4.7 percent of the box
River discharge, GloFAS via Open-Meteo: read live when the 3D twin opens
Vegetation index, MODIS Terra NDVI 8-day: read live when the 3D twin opens
Surface water extent, OPERA DSWx (HLS): the flood pulse: read live when the 3D twin opens
Land cover classes, MODIS IGBP (annual): 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.
Power plantsThe hydropower, oil, waste and biomass plants inside the box with their capacity in MW and primary fuel, the energy node of the loop.Power plants: Global Power Plant Database v1.3.0 (2021), World Resources Institute and partners, CC BY 4.0. release 1.3.0, 2021-06-02.Estimate: A 2021 snapshot, never current operating status.
Cropland, tree cover, water and built-up shares (ESA WorldCover 2021)The share of cropland, tree cover, permanent water and built-up land in each of 200 by 200 cells, summarised at build time from the 10 metre product; the food and ecosystem nodes of the loop.(c) ESA WorldCover project 2021 / Contains modified Copernicus Sentinel data 2021 processed by ESA WorldCover consortium (CC BY 4.0); dataset: Zanaga, D. et al. (2022), ESA WorldCover 10 m 2021 v200, doi:10.5281/zenodo.7254221. read 2026-10-17.Estimate: A 2021 classification at 10 metres summarised to cells of about 1.4 kilometres from 16 sub-samples; not a crop yield, a harvest area or a wetland inventory.
River discharge, GloFAS via Open-MeteoDaily Mekong discharge at the Kratie cell with the member range for the next 30 days, and on click anywhere in the box; the water inflow of the loop.Weather data by Open-Meteo.com(CC BY 4.0); river discharge: contains modified Copernicus Emergency Management Service information 2026 (GloFAS); never a flood warning. Live: this page requests flood-api.open-meteo.com when the layer is opened; the data date is printed with it.Estimate: Model output (forecast or reanalysis), shown with the member range where the API gives one; never a warning. The loop simulator adds one request to the same endpoint with start_date=1984-01-01 and end_date=today for the chosen cell to build the seasonal pulse.
Vegetation index, MODIS Terra NDVI 8-dayVegetation greenness across the basin; the season scrub steps the 8-day periods through the flood pulse.MODIS Terra NDVI 8-day, NASA LP DAAC / LANCE, via NASA GIBS, with the product date. Live: this page requests gibs.earthdata.nasa.gov when the layer is opened; the data date is printed with it.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).Estimate: An indicator of vegetation condition, never yield or production.
Surface water extent, OPERA DSWx (HLS): the flood pulseOpen and partial surface water on the date shown: the lake’s seasonal expansion and contraction.OPERA Dynamic Surface Water Extent from HLS, NASA JPL OPERA (contains modified Copernicus Sentinel data; USGS Landsat), via NASA GIBS, with the product date. Live: this page requests gibs.earthdata.nasa.gov when the layer is opened; the data date is printed with it.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).Estimate: A classification from optical imagery; clouds leave gaps in the wet season; never a flood warning.
Land cover classes, MODIS IGBP (annual)The 500 metre annual land cover classes (croplands, wetlands, forests) for the newest year GIBS serves, draped on the terrain beside the WorldCover shares.MODIS land cover (MCD12Q1, IGBP classes), NASA LP DAAC, via NASA GIBS, with the product year. Live: this page requests gibs.earthdata.nasa.gov when the layer is opened; the data date is printed with it.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).Estimate: A classification, not a crop area statistic.
Why this place: One box of about 270 by 275 kilometres holds the Tonle Sap lake, whose flow reverses with the Mekong flood pulse each year, the Mekong main stem from Kratie to Phnom Penh, the rice plains that the pulse irrigates, the fisheries that feed the country, and the hydropower and thermal plants of the Global Power Plant Database, so the water-energy-food-ecosystems nexus can be taught where the couplings are strong and well documented.Data quality: Copernicus DEM GLO-30 covers the flat basin in nine tiles, the GloFAS cell at Kratie answered 15,416 cubic metres per second through Open-Meteo on 2026-10-17, ESA WorldCover gives cropland, tree cover and permanent water shares per cell and MODIS the annual land cover classes, and OpenStreetMap maps the dams and the named rivers. It connects to the Water-energy-food-ecosystems nexus, Nexus-Based Risk Management (NRM), Systemic, compound andcascading riskand Complex systems and systems modelling disciplines and to the water, energy and food nexus field maps of the ecosystem sites, which draw on the same rows.
Flat plan of the same data: the lake and rivers, the dams, the plants by capacity, the cropland and tree cover cells and the numbers below. The 3D twin opens on devices that can draw it, once its data and code have been checked; discharge, vegetation, surface water and the annual land cover load in the twin on request, each with its data date.
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).
03نەخشەی زیندوو
Hazards and exposure in Middle East and North Africa
Flood water, active fires and surface heat beside population and night-time lights, over Middle East and North Africa.
نەخشە کارلێککارەکە JavaScript پێویستە؛ لیستی چینەکان و سەرچاوەکان لە خوارەوەن.
Hazards and exposure, framed on Middle East and North Africa.بەرهەمی ماهەوارە و مۆدێل وەک NASA بڵاوی دەکاتەوە، هەر یەکەیان بە بەرواری خۆی. نیشاندەرن، نەک هەڵسەنگاندنی هیچ شوێنێک.
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).داتای کراوەی NASA
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).داتای کراوەی NASA
بەرهەمە نزیک-کاتی-ڕاستەقینەکانی VIIRS (لافاو، پلەی گەرمیی ڕووی زەوی، بەفر، ڕەنگدانەوەی چاککراو)، NASA LANCE؛ imagery via NASA GIBS. ڕەنگەکان لە نەخشەی ڕەنگی بڵاوکراوە دووبارە کێشراونەتەوە؛ بەهاکان لە خانەکانی H3 دا تێکڕا کراون لەو شوێنەی نیشان دراون (دەستکاریکراو). داتای کراوەی NASA
NASA Fire Information for Resource Management System (FIRMS), VIIRS 375 m active fire product, NASA LANCE; vector tiles via NASA GIBS. ڕەنگەکان لە نەخشەی ڕەنگی بڵاوکراوە دووبارە کێشراونەتەوە؛ بەهاکان لە خانەکانی H3 دا تێکڕا کراون لەو شوێنەی نیشان دراون (دەستکاریکراو). داتای کراوەی NASA
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. ڕەنگەکان لە نەخشەی ڕەنگی بڵاوکراوە دووبارە کێشراونەتەوە؛ بەهاکان لە خانەکانی H3 دا تێکڕا کراون لەو شوێنەی نیشان دراون (دەستکاریکراو). doi:10.7927/H49C6VHW. CC BY 4.0
VIIRS Black Marble night-time lights, NASA Goddard Space Flight Center; distributed by the NASA Level-1 and Atmosphere Archive and Distribution System (LAADS DAAC); imagery via NASA GIBS. ڕەنگەکان لە نەخشەی ڕەنگی بڵاوکراوە دووبارە کێشراونەتەوە؛ بەهاکان لە خانەکانی H3 دا تێکڕا کراون لەو شوێنەی نیشان دراون (دەستکاریکراو). داتای کراوەی NASA
بەرهەمە ئاسمانییەکانی MODIS و VIIRS، NASA LANCE و LAADS DAAC؛ imagery via NASA GIBS. ڕەنگەکان لە نەخشەی ڕەنگی بڵاوکراوە دووبارە کێشراونەتەوە؛ بەهاکان لە خانەکانی H3 دا تێکڕا کراون لەو شوێنەی نیشان دراون (دەستکاریکراو). داتای کراوەی NASA
ASTER GDEM بەرهەمی METI و NASA ە (ASTER Global Digital Elevation Model V003, NASA LP DAAC); imagery via NASA GIBS. ڕەنگەکان لە نەخشەی ڕەنگی بڵاوکراوە دووبارە کێشراونەتەوە؛ بەهاکان لە خانەکانی H3 دا تێکڕا کراون لەو شوێنەی نیشان دراون (دەستکاریکراو). 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. داتای کراوەی NASA
ڕووداوە ڕاستەوخۆکان: NASA Earth Observatory Natural Event Tracker (EONET)؛ ڕووداوەکان نیشانەدەرن و بەستەری سەرچاوەی ڕەسەنی خۆیان دەهێڵنەوە.
ڕاستەوخۆ: NASA EONET ڕووداوەکان نیشانەدەرن، نەک ئاگادارکردنەوەی دەسەڵات.
ڕاستەوخۆ: U.S. Geological Survey ڕووداوەکان نیشانەدەرن، نەک ئاگادارکردنەوەی دەسەڵات.
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).
ڕووناکی شەو، ڕۆژانە: VIIRS Black Marble (VNP46A2)، NASA LAADS DAAC · 12ی تشرینی یەکەمی 2026
قووڵیی ئۆپتیکیی ئەیرۆسۆل، ڕۆژانە: VIIRS NOAA-20 Deep Blue AOD، NASA LANCE · 13ی تشرینی یەکەمی 2026
04The subject
The subject, methods and measures and debates and bodies
The field and its scope
For analysts, policy advisers and researchers who need to assess and communicate low-probability, high-consequence risks to humanity with honesty about what the probabilities rest on.
Quantities and units
Methods and their limits
Each method is listed with what it assumes and where it fails.
What the field debates
Bodies that set practice, and the data they publish
Bodies and standards are named so learners can find and apply their published work; the Academy teaches their use and links to the publisher, and no affiliation is implied.
05The method
Soot in the stratosphere: from an annual probability to the food a reserve can cover
A rare event has a small annual probability that compounds over a planning horizon; its impact runs from soot or sulphate in the stratosphere to cooling, to lost calories, to the months a food reserve can cover, and each link carries a range that an honest assessment states.
Sources:Robock, Oman and Stenchikov, Nuclear winter revisited with a modern climate model and current nuclear arsenals(2007); Xia et al., Global food insecurity and famine from reduced crop, marine fishery and livestock production due to climate disruption from nuclear war soot injection (2022); Rougier, Sparks, Cashman and Brown, The global magnitude-frequency relationship for large explosive volcanic eruptions (2018); Cotton-Barratt, Daniel and Sandberg, Defence in depth against human extinction: prevention, response, resilience, and why they all matter (2020).
06At a glance
At a glance, with 5 related topics
Global catastrophic risks at a glance
risksacademy.comsystems-nexusdiscipline
Global catastrophic risks at a glance
Open, 0
In preparation, 1
Also taught here, 2
Subtopics, 8
Drawn as a network cascade: the discipline as the source, its courses as the first tier and connected disciplines as the second.Course codes from the curriculum; study levels L1 to L4.
تۆماری تەواوکردن: خولەکە، وەشانەکەی، بەروار و ئەوەی هەڵسەنگێنرا، بە شێوەی بنەڕەتی تایبەتە و تۆ هاوبەشی دەکەیت. لەسەر یەک کەڵەکە دەبێت بۆ دەستکەوتەکانی بواری زانستی، بەش و بەرنامە. تۆمارێک دیاری دەکات چی خوێندراوە و هەڵسەنگێنراوە و لێهاتوویی پشتڕاست ناکاتەوە؛ مۆڵەت، ناونیشانی پیشەیی یان دۆخی دامەزراندن نییە.
داتا و شوێنەکان لە کوێوە دێن؟
هەر کۆلێژێک لەسەر هاوشێوەیەکی دیجیتاڵیی شوێنێکی ڕاستەقینە وانە دەڵێتەوە کە لە داتای کراوە بنیات نراوە؛ هەر چینێک دابینکەر، مۆڵەت و بەروارەکەی هەڵدەگرێت، و هەر ئەنجامێک لە Academy سەرچاوەکەی دیاری دەکات. نەخشە و وێنەکان نیشاندەرن بۆ فێرکردن، هەرگیز هەڵسەنگاندنی شوێنێک نین.
How do I take part beyond the courses in global catastrophic risks?
خانەیەکی لێهاتوویی لە سێ تا حەوت کەس پێکبهێنە، ڕێڕەوێکی هاوبەش بخوێنە، ئەرکێکی سەرپەرشتیکراو لە National Working Groups وەربگرە، یان کۆمەڵێک لە دامەزراوەکەتەوە بهێنە. بۆ ڕێکخراوەکان.
زاراوە سەرەکییەکان
دەستەواژە
Global catastrophic risk
A risk that could cause severe harm to human well-being on a global scale.
دەستەواژە
Low-probability, high-impact event
An event that is unlikely in any year but would have very large consequences.
دەستەواژە
Existential risk
A risk that threatens the survival of humanity or its long-term potential.
دەستەواژە
Near-Earth object
Anasteroidor comet whose orbit brings it close to the Earth.
Reportsبەشداری بکە
لەم لاپەڕەیەوە بەڵگە پێشکەش بکە.
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
پەیوەندیدار
Around Global catastrophic risks
مەترسییە کارەساتبارە جیهانییەکان
Prepare with a related course
Open courses in connected disciplines teach the methods this discipline will build on.
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