Climate and hazards
Floods, droughts, heatwaves, storms, wildfires and earthquakes are natural hazards; whether they become disasters depends on exposure, vulnerability and preparation. A warming climate changes the frequency and intensity of several hazards and makes the past a weaker guide to the future. The Global Centre for Risk and Innovation (GCRI) studies hazard science together with its limits: what can be forecast, what can only be bounded as a range of scenarios, and what remains unknown. This page is part of global challenges.
- 01In briefThe short answer
- 02The challengeHazards are changing faster than the records that describe them
- 03Limits of predictionForecasts, projections and scenarios answer different questions
- 04MethodsThe science behind hazard evidence
- 05Key termsTerms used on this page
- 06Across the programmeGovernance and finance views of the same hazards
GCRI · Institution · service level R0
The short answer.
Climate and hazards covers floods, droughts, heatwaves, storms, wildfires and earthquakes, which become disasters only through exposure, vulnerability and weak preparation. A warming climate changes the frequency and intensity of several hazards and makes the past a weaker guide; GCRI studies what can be forecast, what can only be projected and what must be explored with scenarios.
Climate and hazard exposure in Southern Africa.
Coastal exposure, deserts, deltas and glaciers across the region, shown for Southern Africa as an example geography for this subject.
Hazards are changing faster than the records that describe them.
The past is a weaker guide
Return periods estimated from historical records assume a stable climate. Where that assumption fails, design standards and insurance estimates drift from reality.
Hazards that coincide
Heat with drought, storm surge with river flooding, or wildfire followed by debris flows do more damage together than separately.
Where people and assets are
Growth in floodplains, coasts and fire-prone land often matters as much for losses as changes in the hazard itself.
Forecasts, projections and scenarios answer different questions.
| Product | What it can tell you | What it cannot |
|---|---|---|
| Weather forecast | Likely conditions over days, with skill that falls as lead time grows | Precise local impacts far ahead |
| Seasonal outlook | Shifts in the odds of wetter, drier, warmer or cooler conditions | Whether a given event will occur |
| Climate projection | Plausible ranges under stated emissions pathways | A prediction for a specific year or place |
| Stress scenario | How systems behave under a severe but plausible event | The probability of that event |
GCRI labels every result as forecast, modelled, scenario or observed, and never presents a scenario as a prediction.
The science behind hazard evidence.
The work draws on climate and atmospheric science, extreme value theory and tail risk, Earth observation and forecasting and time-series analysis. Field work is organized through the Climate and Hazards platform, in development, and the climate and hazards field gateway.
Terms used on this page.
Each term as this page uses it. Where a standard-setting body defines the term, the wording follows that body.
| Term | Definition |
|---|---|
| Hazard | A process, phenomenon or human activity that may cause loss of life, injury or other health impacts, property damage, social and economic disruption or environmental degradation, in UNDRR terminology. |
| Exposure | The people, infrastructure, housing, production capacities and other tangible assets located in hazard-prone areas, in UNDRR terminology. |
| Vulnerability | The conditions that increase the susceptibility of people, assets or systems to the impacts of hazards. |
| Return period | The average interval between events of a given size, equal to the inverse of the annual exceedance probability; a one-in-a-hundred-year flood has a one in a hundred chance of being exceeded in any year. |
| Non-stationarity | A change over time in the statistical behaviour of a series, such as a trend in flood peaks, which invalidates return periods estimated from a fixed past. |
Governance and finance views of the same hazards.
How institutions govern climate and nature risk is examined by The Global Risks Forum (GRF) under climate and nature governance. What hazard evidence means for financial institutions is examined by The Global Risks Alliance (GRA) under climate and nature risk. Related GCRI pages: disaster resilience and early warning research.
Questions and answers.
Does GCRI issue hazard warnings?
Can climate change be blamed for a specific event?
Why does GCRI talk about exposure and vulnerability, not only hazards?
Where can I find country-level hazard evidence?
Around GCRI.
Start with an enquiry.
The current service level is R0: information and enquiries. An enquiry receives a reference and names the next step; applications, payments, compute allocations and registrations open only when their team, terms and review capacity exist.