Methodology

Strata uses a Convergence of Evidence approach to identify

Strata aggregates spatial data for climate, environmental, and peace and security stress indicators. It combines these with data layers on population exposure and socioeconomic vulnerability to produce hotspot maps that highlight where the climate, environmental and security stresses overlap, and where they coincide with populations vulnerable to these stresses.

The combination of data layers is based on the convergence of evidence approach, developed by the European Commission’s Joint Research Center. With this approach, each indicator is assigned a threshold value, above which the indicator is considered to be “red flagged”, i.e. at a “level of concern”. The hotspot map shows the sum of all the red flags across the chosen indicators, weighted by the population exposure and vulnerability.

You can find more detailed information about Strata’s methodology in our user guidebook and scientific publication.

The criteria that underpin the methodological development include:

  • → A transparent, robust theoretical framework
  • → User-friendly and easy to customise
  • → Aggregation and disaggregation of selected stresses
  • → Integration of climate and environmental stresses, peace and security stresses, and socio-economic vulnerability
  • → Multilevel approach from a sub-national to a global scale
  • → Support users in their choice of actions and solutions

Visualise

Strata provides various ways to visualise your custom climate security analysis.

Strata’s central feature is the hotspot map which visualises where environmental and climate-related stresses converge with insecurity and socio-economic vulnerability.

The hotspot results can be viewed as a:

  • bitmap: this shows the raw output of the hotspot calculation at the pixel scale available based on the indicators chosen;
  • heatmap: this smooths out the bitmap and highlights that impacts are likely to be experienced beyond the pixel being flagged;
  • district and regional-level maps: the hotspot data is aggregated within political boundaries, available in the dashboard;
  • charts and diagrams: they deepen insights into specific regions and indicators, available in the dashboard.

Users can view the separate data layers feeding into the Strata hotspot score, including the individual stresses, exposure and vulnerability scores. Further, users can choose from a range of basemap options to clearly identify locations below the hotspots, including satellite, terrain and hybrid options.

All of the maps, charts, and diagrams can be downloaded in picture format and as a data layer. The Strata guidebook provides more information about the methodology, customisation, visualisation, and interpretation of the outputs.

Strata Interactive dashboard.

Customise

On the left hand panel, Strata allows users to select indicators from different thematic baskets and run dedicated analysis. Each indicator block allows you to choose an indicator from the drop-down menu. You can add or remove indicators by dragging and dropping blocks, or by selecting different indicators from the drop-down menu.

By selecting “Advanced options” on the indicator block you can set your own threshold for this indicator. Before using advanced options, we recommend you read the section on indicators and thresholds in the User Guide since each indicator threshold is uniquely defined.

The code-free analysis and dashboard is powered by EarthBlox. The data incorporated in Strata is sourced from public, trusted sources that are available on Google Earth Engine.

Co-design

UNEP Haiti 2017

To incorporate the practitioners’ perspective in the project. The indicator selection, scientific methodology, and platform features are constantly strengthened with consultation rounds to ensure that Strata meets the needs and requirements of end-users in terms of applicability, usage, and uptake.

While Strata’s methodology has been developed based on a literature review of previous approaches to mapping and aggregating indicators of climate security, a set of dedicated discussions with experts from academia, think tanks, governments and international organisations continuously refine sand strengthens its approach.

Strata’s glossary provides definitions for key concepts and describes how data is processed and presented. The definitions take into account multidisciplinary perspectives across scientific fields, selecting definitions typically used in different literatures. The full glossary can be accessed through the link above. Key definitions to note are:

  • Climate-related security risks: Risks that can simultaneously undermine the security of humans, communities, states, the international system, the environment and ecology as a consequence of changing climate patterns, and their impacts on biophysical and socioeconomic systems.
  • Hotspot: A location where there is a convergence of stresses (which may include climate, environment, vulnerability, peace and security). A hotspot implies that further attention is required in that location. It does not mean that an event has occurred, nor does it imply any quantitative probability of anything occurring.
  • Stress: A natural or human-induced event (slow-onset or rapid-onset), trend or physical impact that may cause adverse effects to human security or the environment, or strain a system such as a local community or a state. (Also referred to as a “hazard”).
  • Indicator: A quantitative (georeferenced) dataset used to monitor a natural or socio-economic characteristic. This is either a data layer itself, used directly, or is based on one or more data layers combined in some way. For example, “rate of deforestation” is an indicator calculated using data layers of forest cover and forest change.
  • Basket: A basket is a categorisation of indicators and/or indices according to sector, issue or other logical or theoretically-defined grouping system. Strata categorises its indicators into three main baskets relevant to climate security: 1) Environment and climate; 2) Peace and security; and 3) Socio-economic vulnerability.
  • Threshold: The level of an indicator beyond which impacts are likely and/or action needs to be taken. Thresholds are generally set based on guidelines in scientific literature (e.g. heatwave is flagged when Maximum Apparent Temperature >41°C for at least 3 consecutive days). When no guidelines are available, they are calculated based on historical conditions. Details of how each threshold is calculated can be found in the technical documentation.
  • Vulnerability: The propensity of exposed elements (people or assets) to be adversely affected by a hazard, as determined by physical, social, economic or environmental factors or processes.

FAQ

Frequently asked questions

If you cannot find the information you need below, do not hesitate to contact us with your questions.

Strata is publicly available and can be used by anyone interested in exploring the convergence of environmental and climate stressors with social and economic variables relevant to peace and security. Strata has been developed for analysts, practitioners and policymakers working in the fields of climate change adaptation, natural resource management, and peace and security in conflict-affected regions. Its objective is to streamline climate security data and insights in their daily work and to support informed decision making and policy and programme development, It can also be a useful tool for researchers, analysts and students.

Strata is conceptualised as an environmental digital public good, and is free to use.

To get started, click here to access the platform. A quick starter guide is available here.

Follow the instruction on the access page to:

  1. use Strata’s open-access dashboard,
  2. create an account to use Strata’s full set of analytical features, and/or
  3. sign in as an existing user.

The main outputs of Strata are climate security stress maps visualised as heatmap and bitmap hotspots, together with diagrammes and tables to support interpretation of climate-related security risks. The goal of these output products is to streamline climate security data in peacebuilders and environmentalists daily work. They can strengthen:

  • baseline analyses (environmental, climate, conflict, political, multidimensional crisis situation),
  • design, monitoring, and evaluation of climate and environmental programmes, of conflict prevention and peacebuilding programmes,
  • awareness raising and training,
  • in-depth assessments, e.g. for climate-related strategies and environmental policies,
  • (adhoc) advice and prioritization for decision makers.

Strata is not designed as a forecasting tool to predict where certain impacts will be highest. Rather, it is designed to indicate locations where different stressors are occurring simultaneously, given the available time periods of each of the indicators.

Many of the stresses shown in Strata, whether climatic, environmental or security related, may be causes of other stresses, and there are complex pathways between different stresses, vulnerabilities, and impacts on people. Strata’s hotspots show the co-occurrence of risk factors, but do not indicate whether there is any connection, correlation, or causal pathway between those indicators. The quantitative data alone cannot fully explain these pathways and needs to be combined with local, in-depth, contextual, qualitative knowledge.

Strata’s indicators and datasets have different levels of confidence associated with them. These might be associated with the source of the data, the inputs it is based on, measurement errors, how frequently the dataset is updated, or the range of possible future conditions. While Strata does not currently provide an assessment of the confidence associated with each indicator, users should be aware that there will be uncertainty associated with the results, and should take this into account in their interpretation of the hotspot maps.

You can find the Strata Guidebook on under Resources. It provides support on the use and interpretation of Strata.

To combine the indicators across the three baskets into a hotspot map, Strata uses a methodology based on a Convergence of Evidence approach. The Convergence of Evidence is a methodology developed by the European Commission Joint Research Centre for the World Atlas of Desertification. For each of the selected variables related to climate and environmental security, a threshold is defined above which the level of that variable is considered a stress. The Convergence of Evidence approach stacks all the data layers of the selected indicator and counts how many of them surpass a critical threshold. The hotspot map shows the sum of all the red flags, i.e., the number of indicators that passed their threshold, across the chosen indicators, weighted by the population exposure and vulnerability. Some indicators have absolute thresholds fixed across all locations (e.g., peace and security); others have thresholds relative to past conditions (e.g. drought and deforestation) or relative to other locations (e.g. internally displaced people and access to healthcare). By selecting ‘advanced options’ on the indicator in the Strata platform, you can set your own threshold per indicator. Before using advanced options, we recommend you read the section on indicators and thresholds in the Guidebook since each indicator threshold is uniquely defined.

Strata has no predictive or future modelling capacity itself. However, it includes 3 variables representing future climate risks derived from climate projection models: flood likelihood, precipitation, and temperature. For these predictive variables one can select between two climate change scenario (RCP4.5 or RCP8.5), as well as the time horizon of the projection (2030, 2050, or 2080).

A climate-security hotspot is a location where there is a convergence of stresses related to climate and environment, socioeconomic vulnerability, and peace and security. A hotspot implies that further attention is required in that location; it does not mean that an event has occurred, nor does it imply any quantitative probability of anything occurring.

Strata works with three main baskets of indicators:

  • Climate and environment: Drought (agricultural), drought (meteorological), heatwave, deforestation, land degradation, flood likelihood, and coastal inundation risk.
    • Predictive trends: flood likelihood (future), precipitation (future), temperature (future).
  • Peace and security: Recent explosions/remote violence, recent violence against civilians, recent protests, recent riots, history of battles.
  • Socioeconomic vulnerability: Population density, percentage of elderly, children, and female population, number of internally displaced people, urban expansion, travel time to urban area, sanitation (fresh water availability), access to electricity, access to healthcare, irrigation, food insecurity.

Details of the data sources and thresholds used for each indicator can be found in the Overview of indicators and data sources as well as in the Guidebook.

Strata uses publicly available geospatial datasets, most of them derivatives of satellite imagery. All datasets incorporated into Strata have been tested and validated scientifically in relation to a defined set of criteria relevant to climate security and the provision of safe and trusted data.

The data sources for each individual indicator are specified on the online platform. Details on all the data sources is explicitly included in the Overview of indicators and data sources as well as in the Guidebook.

We are always looking to improve our data. If you are experiencing issues with a dataset or believe it is outdated or inaccurate, please contact our support team as described in the Contact tab.

UNEP Strata. 2022. United Nations Environment Programme. unepstrata.org (date accessed: Day Month Year).

Please note that citation of the original data provider(s) is required for any map created on the platform. This is a requirement for use of many datasets, and is a standard good practice. You can find links and references to the original data providers in the platform itself and in the Overview of indicators and data sources.

The development of the first prototype of Strata (for Somalia) was finalised in December 2021. During 2022, Strata has been expanded to the Horn of Africa region, included climate chagne projection indicators and improved its ease-of-use. Upcoming developments include a catalogue of Nature-based Solutions for Peace and Security, further regional expansions, continued improvement of its ease-of-use, automated alert functions, and indications of confidence/uncertainty. Within 2023, Strata will also ensure global coverage.

Strata is fully operational for Somalia since February 2022, and for the whole Horn of Africa region since July 2022. Further regional expansions are planned in the coming months and are prioritized depending on demand and access to regional stakeholders. If you are interested in having Strata available for your region of interest, do not hesitate to contact us and become part of its co-design. Within 2023, Strata will also ensure global coverage.

Strata is continuously being improved in terms of ease-of-use and analytical features.