Future Climate Scenarios for Great Lakes Cities

Plan for a future unlike the past


GLISA partnered with Great Lakes city adaptation practitioners to produce a set of plausible climate scenarios to aid in city and local planning. These scenarios can also be used at larger spatial scales (e.g., county) and are intended to be transferable across cities, meaning the basic scenario details are relevant for any city in the Great Lakes region with the option to customize them further. While the scenarios are informed by climate model projections, they provide much greater detail than what models alone tell us. Although still backed by models and projections, GLISA’s scenarios make it easier to understand what projected climate changes could look like in reality. Communities are also able to customize their scenarios to a greater degree based on the climate impacts that they are most concerned about or that are most relevant for them. This combination of model data and real-world experience represents a holistic and practitioner-driven approach to scenario development. 

Each scenario consists of a narrative description of weather conditions or events with details about sector-specific urban impacts (e.g., city transportation, emergency response, etc.). Cities can customize the impacts described in the scenarios based on their own vulnerabilities and planning priorities to make the scenarios more relevant for their planning needs. Example customizations are provided with each scenario and an accompanying scenario planning workbook also helps guide these customizations. The scenarios can be used as a starting point for thinking about a future that may look different than the past and to develop ideas, recommendations, and plans to better prepare for that future.

Download GLISA’s Scenario Resources

Click the buttons below to access GLISA’s climate scenarios for cities and an accompanying scenario planning workbook.


Climate Change Scenarios for Cities Climate Change Scenario Planning Workbook

Using GLISA's Scenario Resources

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Scenario Development 

Future climate scenarios can come in many different formats depending on who is developing them and who is using them. Typically climate model data is used as a starting point for thinking about the future. Future climate scenarios take it a step further and can provide quantitative data, qualitative narratives, or both. Quantitative information coming directly from climate models is limited to how different climate variables, like temperature or precipitation, may change over time. However, many variables of interest to practitioners, such as freezing rain or wind storms, are not available or reliable in climate model projections. In order to address this gap, GLISA’s scenarios are narrative-based and include plausible descriptions of weather and climate events that city practitioners may have to respond to in the future. GLISA’s team of climate experts use knowledge about physical climate processes, combined with climate projection data, to develop these scenarios about the future. The weather and climate challenges that define the scenarios are based on real concerns informed by city practitioners in GLISA’s Practitioner Working Group regarding current and future climate impacts.    

The scenarios presented here rely heavily on input from practitioners who understand well the climate impacts that cities face. The scenarios leverage the expertise embodied in GLISA’s Practitioner Working Group and professionals in the Great Lakes Climate Adaptation Network (GLCAN) and are designed around climate concerns (e.g., flooding, runoff, heat stress, etc.) raised by partners in these groups. GLISA developed narratives of climate patterns (long-term) and weather events (short-term) that speak directly to these concerns and offer plausible descriptions of future climate-related challenges. 

Read more about GLISA’s scenario planning approach and past work here.

How to use the Scenarios

The scenarios provided here offer a starting point for thinking about how cities may be impacted in the future by weather and climate events. Given the interconnected nature of public and private entities, city operations, and ways in which cities function, scenario planning requires the participation of diverse stakeholder groups (e.g., residents, business owners, transportation services, community organizations, and multiple municipal departments – health and human services, city planners, parks and recreation, wastewater managers, etc.). The impacts described in the scenarios typically cross many of these sectors, so all relevant stakeholders, including those who live, work, and play and those with and without decision making power within a community, can participate in the conversation. Some scenarios may be more or less relevant to specific cities depending on their vulnerabilities and capacity to manage the type of risks described in each scenario. 

Below is an outline of the basic steps GLISA follows in using scenarios in practice through scenario planning exercises. A more detailed description is available in the Scenario Planning Workbook.


The first step of the scenario planning process is for a core team of vested individuals to: 1) define the main problems, challenges, or management areas that will be addressed in the scenarios and 2) identify a diverse team of stakeholders willing and able to bring their expertise and experience to the process. This team should include anyone who will be asked to use the scenarios to inform future planning and it is important to engage stakeholders outside of government early in the process. It may help to start with a conversation about past and current vulnerabilities or challenges the city has faced with respect to climate and/or weather events. A formal vulnerability assessment is not required, but identification of the types of impacts that are most challenging for the city related to weather and climate (e.g., extreme heat, flooding, infrastructure integrity, etc.) is helpful to guide the selection of meaningful scenarios.


Several different scenarios are available that highlight various potential future challenges cities may face. The scenarios are organized by season, as climate changes are anticipated to have varying degrees of severity and variability throughout the year. The core team should determine which scenarios are most salient based on their past experiences, current challenges, and future management decisions. They should choose a small number (2-3) to focus on initially. These can be used independently of one another or in series where a scenario from each season is selected to depict an entire year (if a seasonal scenario describes conditions from earlier in the year, the series must reflect this for physical consistency across narratives).


In a workshop setting, all stakeholders will come together to customize and personalize the selected scenarios. Depending on the size of the group, scenarios may be discussed collectively or sub-groups may be assigned a specific scenario to focus on. Further guidance on the planning and execution of the workshop is available in the Scenario Planning Workbook. The goal is for each stakeholder to become familiar with the scenario(s) they’ve been assigned and as a group customize it to include details about local impacts not already identified. There is a lot of room for creativity, especially when describing climate impacts, because each city can manage and/or adapt to climate and weather risks differently. Within each scenario GLISA offers suggestions for how to further customize the scenario, but users are not limited to these options.


The scenarios are ultimately a planning tool for thinking about a future that is different from the past. They can be used to identify planning priorities, necessary changes to existing practices, and potential opportunities.

Scenario Customization Support

GLISA offers a basic template workbook to help facilitate the scenario planning process that includes conversation prompts to identify climate vulnerabilities, management goals, and priority areas to focus on in future planning and management decisions. The scenarios and accompanying workbook were designed for cities and communities to use without the required participation of a climate expert, however, this process will benefit from such expertise if it is available. GLISA is also available to provide consultation on this process and to discuss partnering together to develop a more customizable experience.