Illustrative: an ice sheet in steady flow, faster towards the margin, and a calving shelf
Risk Academy, led by the Nexus Consortium · Course catalogue · Earth and Environmental Sciences
Climate and Ocean Sciences
Cryosphere and mountain systems
Cryosphere and mountain systems, taught twice over: as the working methods of the field and as its frontier since 2024, with labs on the Academy's tools, open data and the Nexus Standards.
Cryosphere and mountain systems: foundations and practice
This area covers glaciers, ice sheets, permafrost, snow and sea ice, and the mountain systems whose water, hazards and livelihoods depend on them.
- Level
- L2 Intermediate
- Study time
- about 24 hours (planning estimate)
- Status
- Planned
- Prerequisites
- An L1 course in the area, or an entry review
Why now
The first community estimate of glacier mass loss from all observation methods (GlaMBIE, Nature, 2025) found glaciers lost about 273 billion tonnes of ice a year from 2000 to 2023, with the loss rate rising by over a third in the second half of the period, and glacial lake outburst floods now threaten about 15 million people. Nature, Community estimate of global glacier mass changes from 2000 to 2023 (The GlaMBIE Team), 2025
Learning outcomes
- Define glacier mass balance and the other key terms of the discipline and use them correctly in a written case
- Explain glaciers and glacier mass balance and ice sheets and their contribution to sea level with a worked example and its source
- Apply the discipline's method to a documented case and explain each result with its source
- Analyse a named case against permafrost and ground ice, stating evidence, date and limits
Modules
- Glaciers and glacier mass balance
- Glaciers and glacier mass balance
- Ice sheets and their contribution to sea level
- Permafrost and ground ice
- Snow cover and snowmelt runoff
- Snow cover and snowmelt runoff
- Sea ice
- Glacial lake outburst floods
- Rock and ice avalanches and mountain slope failure
- Rock and ice avalanches and mountain slope failure
- Mountain water towers and downstream water supply
- Cryosphere observation from satellites and field networks
- Lab: the discipline's method
- Warming lowers a glacier's annual mass balance by a sensitivity the record measures; the loss shrinks the area that melts, so runoff first rises then falls, the peak water of a mountain basin; the mass lost reaches the ocean at 362 gigatonnes per millimetre of sea level, and the year of peak water is the decision point for the people downstream.
- Work the method through a documented case and explain each result
- Read the method's sources and stated values
Labs with Academy tools
- MethodFrom a degree of warming to peak water: how a glacier's mass balance drains a water tower and raises the seaThe discipline's method on the discipline page, with its cited sources, worked through a documented case
- InstrumentTerrain cross-sectionA faculty instrument on the faculty page, run on the faculty's digital twin data
- InstrumentIndex timelineA faculty instrument on the faculty page, run on the faculty's digital twin data
- Twin builderDigital twin builderBuild the faculty's place in 3D, switch layers and read the credits and dates of each
- Map layerSurface water, 30 m (OPERA DSWx-HLS)An open map layer the Academy's licence register admits, read in the map tools
- Map layerSurface water through cloud, 30 m (OPERA DSWx-S1 radar)An open map layer the Academy's licence register admits, read in the map tools
- Map layerRiver discharge forecast, 30 days with range (GloFAS via Open-Meteo)An open map layer the Academy's licence register admits, read in the map tools
- Foundry roomChange room, NXS-EOP (earth observation and digital twins)Glacier, snow cover and sea ice change products
- Foundry roomWarning Desk room, NXS-EWS (multi-hazard monitoring and warning)Warning-support products for glacial lake outbursts and mountain slope failure
Open data
- NSIDC Sea Ice Index NSIDC open use; link only
- IMBIE ice sheet mass balance link only
Assessment
- 40%Lab recordWork the discipline's method through a documented case and explain each result with its source and date
- 40%Case memoApply the discipline's methods to a named place or organisation, stating evidence and limits
- 20%Key terms checkShort answers on the key terms, marked against the definitions
Delivery
- Self-paced online, with the labs in the browser
- Cohort study over six to eight weeks, with a weekly lab review
- Co-delivered with a partner institution, inside its own courses
Partner on this course
- Co-teach a module and bring a current case from your work
- Host a cohort for your learners, with your own schedule and review
- Contribute a lab: a dataset your institution publishes openly, or a model
- Review the course content and its references before it opens
- Translate the course and adapt its cases to your region
How institutions and experts take part
In the Academy LMS
- Course on the learning platform
- Intermediate, 4 topics
- Cohort group
- A community group for each cohort of learners
- Achievement
- Recorded on completion of the assessed work
References
Hazards and exposure in the Hindu Kush Himalaya
Flood water, active fires and surface heat beside population and night-time lights, over the Hindu Kush Himalaya.
The interactive map needs JavaScript; the layer list and sources are below.
Layers 3
Hazards and exposure
Keyboard, with the map focused
Hold Ctrl or ⌘ and scroll to zoom
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 and exposure, framed on the Hindu Kush Himalaya.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
- 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
- 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. 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
- 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 (10 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
- Population density, 2020: Population: CIESIN, Columbia University, Gridded Population of the World v4.11 (2018), NASA SEDAC, CC BY 4.0 · static
- Land surface temperature, day, 8-day composite: VIIRS NOAA-20 Level 3, 8-day, NASA LANCE · 14 Sep 2026
- Night-time lights, daily: VIIRS Black Marble (VNP46A2), NASA LAADS DAAC · 12 Oct 2026
- Aerosol optical depth, daily: VIIRS NOAA-20 Deep Blue AOD, NASA LANCE · 13 Oct 2026
How learning runs, as a process you can run
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What is changing, with standards and evidence
Cryosphere and mountain systems: frontier methods
The methods, data, tools and studies that changed cryosphere and mountain systems between 2024 and 2026, taught by reproducing them on open data.
- Level
- L3 Advanced
- Study time
- about 28 hours (planning estimate)
- Status
- Planned
- Prerequisites
- Cryosphere and mountain systems: foundations and practice; Working knowledge of a scripting language (Python or R) for the labs
Why now
The first community estimate of glacier mass loss from all observation methods (GlaMBIE, Nature, 2025) found glaciers lost about 273 billion tonnes of ice a year from 2000 to 2023, with the loss rate rising by over a third in the second half of the period, and glacial lake outburst floods now threaten about 15 million people. Nature, Community estimate of global glacier mass changes from 2000 to 2023 (The GlaMBIE Team), 2025
Learning outcomes
- Explain what changed in cryosphere and mountain systems since 2024 and cite the studies, data or rules behind each change
- Reproduce measuring ice from space on open data and state the uncertainty of the result
- Evaluate a 2024 to 2026 study: its question, data, method, limits and what it changes for practice
- Design an analysis that combines a frontier method with the faculty's instruments, and justify each choice
Modules
- Measuring ice from space
- Altimetry (ICESat-2, CryoSat-2), gravimetry (GRACE-FO) and DEM differencing
- Reconciling methods: the GlaMBIE and IMBIE intercomparisons
- Sea ice extent and thickness records
- Mountain hazards
- Glacial lake outburst floods: inventories, triggers and exposure
- Permafrost thaw, rock-ice avalanches and debris flows
- Case studies: Chamoli 2021 and South Lhonak 2023
- Water towers and downstream risk
- Peak water and seasonal shifts in melt-fed rivers
- Snow water equivalent from models and microwave
- Hydropower and irrigation exposure
- Sea level contribution
- Ice sheet dynamics and deep uncertainty
- Low-likelihood high-impact storylines in IPCC AR6
- Planning horizons for coastal decisions
- Reproduction lab
- Extend the discipline's method with one frontier method and compare its results
- State the uncertainty and the limits of the result
- Peer review against a shared checklist
- Technology that helps and the risks it carries
- Machine learning forecasting, carbon dioxide removal and climate data infrastructure.
- The governance of solar radiation modification and the integrity of carbon removal.
Labs with Academy tools
- MethodFrom a degree of warming to peak water: how a glacier's mass balance drains a water tower and raises the seaThe discipline's method on the discipline page, with its cited sources, worked through a documented case
- InstrumentTerrain cross-sectionA faculty instrument on the faculty page, run on the faculty's digital twin data
- InstrumentIndex timelineA faculty instrument on the faculty page, run on the faculty's digital twin data
- InstrumentDrought and flood recordA faculty instrument on the faculty page, run on the faculty's digital twin data
- Twin builderDigital twin builderBuild the faculty's place in 3D, switch layers and read the credits and dates of each
- Map layerSurface water, 30 m (OPERA DSWx-HLS)An open map layer the Academy's licence register admits, read in the map tools
- Map layerSurface water through cloud, 30 m (OPERA DSWx-S1 radar)An open map layer the Academy's licence register admits, read in the map tools
- Map layerRiver discharge forecast, 30 days with range (GloFAS via Open-Meteo)An open map layer the Academy's licence register admits, read in the map tools
- Research hubResearch hubToday's open data and publications in the faculty's subjects, filtered to this discipline
- Foundry roomChange room, NXS-EOPGlacier, snow cover and sea ice change products
- Foundry roomWarning Desk room, NXS-EWSWarning-support products for glacial lake outbursts and mountain slope failure
Open data
- NSIDC Sea Ice Index NSIDC open use; link only
- IMBIE ice sheet mass balance link only
- ICESat-2 products NASA open data
Assessment
- 50%Method reproductionReproduce one frontier method on open data and state the uncertainty of the result
- 30%Study reviewA critical review of a 2024 to 2026 study: question, data, method, limits, what it changes
- 20%Peer reviewReview two other learners' reproductions against a shared checklist
Delivery
- Self-paced online, with the labs in the browser
- Cohort study over six to eight weeks, with a weekly lab review
- Co-delivered with a partner institution, inside its own courses
Partner on this course
- Co-teach a module and bring a current case from your work
- Host a cohort for your learners, with your own schedule and review
- Contribute a lab: a dataset your institution publishes openly, or a model
- Review the course content and its references before it opens
- Translate the course and adapt its cases to your region
How institutions and experts take part
In the Academy LMS
- Course on the learning platform
- Expert, 6 topics
- Cohort group
- A community group for each cohort of learners
- Achievement
- Recorded on completion of the assessed work
References
- Nature, Community estimate of global glacier mass changes from 2000 to 2023 (The GlaMBIE Team), 2025
- Nature Communications, Glacial lake outburst floods threaten millions globally (Taylor et al.), 2023
- IPCC, Special Report on the Ocean and Cryosphere in a Changing Climate, 2019
- Hugonnet et al., Accelerated global glacier mass loss in the early twenty-first century, 2021
- Huss and Hock, Global-scale hydrological response to future glacier mass loss, 2018
- Bahr, Meier and Peckham, The physical basis of glacier volume-area scaling, 1997
How the mapping to the Nexus Standards is read
The Academy proposes how each discipline teaches toward the Nexus Standards; the mapping is open for public review. 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.
Take part in the work
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Questions, answers and key terms
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Where do the data and the places come from?
How do I take part beyond the course?
Key terms
Glacier mass balance
The net gain or loss of ice of a glacier over a year, the basic measure of its health.
Glacial lake outburst flood
The sudden release of water from a lake dammed by ice or a moraine.
Water tower
A mountain region whose snow and ice store and release water for downstream populations.
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.
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