Charting a new course: How maps are helping communities tackle climate change By Maya Teiman and Shannon Taylor

From youth mapping experts to urban geographers, how innovative mapping tools are guiding adaptation and resilience strategies.

Accra, Ghana’s capital, has witnessed an elevated population growth of around 2% per year over the last few years. The coastal city represents one of the fastest urban growth cases in Africa. In New York City, the largest urban area in the US, population growth was at its highest at 0.5% in the last 20 years, for reference. Currently with 4 million people in its metropolitan area, Accra is expected to surpass the 9 million mark in the next 25 years.

The capital city’s challenges are not limited to tacking its fast paced population increase. Increased flooding has long been a problem in Accra, an issue that David Rain, Associate Professor of Geography and International Affairs at George Washington University, outlines with his research.

Rain spent five years in Ghana between 2008 and 2013 investigating how social dynamics in Accra are affected by environmental challenges through the lens of mapping. In an interview, he shared how mapping surface types, among other aspects, is essential to understanding and mitigating pressing issues like flooding.

Photos - Courtesy of David Rain

Maps as problem solvers

Mapping surface types is essential in determining what percentage of the roofs, roads and other surfaces in an urban space are permeable, meaning they allow water to pass through. The less permeable surfaces, the more prone to flooding an area can be. Urbanization is often characterized by an increased presence of concrete roads, roofs, sidewalks, among other surface types that don’t typically let water filter through.

“Spatial data can come in any different size or look, but basically, spatial data has some kind of reference to a real world point on the surface of the Earth”.

In a place like Accra, where fast paced population growth is met with a flood prone region, mapping permeable surfaces can be essential in allowing the city to understand and address their environmental needs. To accurately map out which zones are at risk of flooding, Rain highlights how gathering spatial data is essential to the process.

Why are maps important?

Instead of saying Accra floods every rainy season, where exactly does it flood? And how bad is it and who is affected by it? - David Rain

To accurately make spatial data accessible, the use of geographic information systems, or GIS, becomes essential. GIS uses a computer system that allows this data to be linked to an exact coordinate on the Earth's surface. GIS users can contrast and compare spatial data, allowing them to understand how different factors in a specific location might relate to each other, such as flooding area and surface types.

Photo - Courtesy of David Rain

Precise data that depicts surface area and population growth in an ever-changing urban landscape can be difficult to obtain. To successfully conduct their research, Rain and his team developed an innovative data collection method shown on his paper “Accra Ghana: A City Vulnerable to Flooding and Drought-Induced Migration”, which received notable recognition with over 173 citations. By mapping all the waterways in Accra, including drainage canals, they were able to identify how the closer to a drainage canal a family lives, the higher the risk of being affected by floods. Rain explains how houses located closer to drainage canals are often a more affordable option, compared to pricier alternatives in areas less prone to flooding. His work highlights how mapping socioeconomic and environmental factors is essential to understanding how climate risks affect vulnerable populations in growing cities like Accra.

Maps are a way of making problems visual, and therefore, solvable - David Rain

As climate change and sea level rise are increasingly impacting communities all over the world, more and more people will be needed in the fight to protect coastal residences and developing nations. YouthMappers is a program that teaches students the importance of digital literacy and geospatial technology skills to address local issues. Co-founded in partnership with Texas Tech University, George Washington University, and West Virginia University, the organization is now an international community of students, teachers, and researchers with over 700 chapters worldwide. By contributing to open-source mapping projects, students involved with YouthMappers make their data freely available not only to the map making community, but anyone with access to the internet.

Photo - Courtesy of David Rain

"We can't wait for governments to update the maps all the time," said Richard Hinton, George Washington University Professor and manager of the school’s Spatial Analysis Lab. Hinton has been with YouthMappers since it began in 2014. As one of the founding academic advisors to the project, he highlighted how the project was born out of the need for more communities to be able to identify and address their own geospatial issues.

According to Hinton, the benefits of YouthMappers have been substantial, not only for GW students but for students around the globe. YouthMappers offers a leadership fellowship that students can apply for which includes a week’s worth of hands on training; GIS instruction, leadership skills, and communication skills. Although the selection process is rigorous, enrollees receive everything from leadership training, to technical GIS instruction, to practice utilizing open-source mapping projects, and Qgis and GIS products. The fellowship training has no out-of-pocket expenses for the students and is entirely covered by YouthMappers.

YouthMappers make socio-economic and environmental changes tangible because of the accessibility and open data sources collected by students. One example is of a student in Kathmandu, Nepal who noticed several trash dump sites within their community. This was a health hazard as well as unsightly. This student identified all the places where trash was building up and put them on a map. Hinton states the student can actually bring the community leaders together and show the locations of where the dump sites are and look for resources to combat dumping or other issues the community faces.

Photo - Courtesy of David Rain

"Impacting change like that is really, really, really powerful. I think that a student can come in and do that, because they have this sort of knowledge of open source datasets and geography to sort of bring those together, and then all those in power accountable for it"-Richard Hinton

Across the entire country, YouthMappers members have been able to contribute an extensive amount of entries into the OpenStreetMap database, as shown on the heat map on the right. According to Rain, there is a growing movement of populations towards urban areas in Ghana, partly due to adverse climate circumstances. As these trends continue, YouthMappers is already supplying vital new data on evolving population distribution trends in the Ghanaian context.