GRID3’s support across various African borders enabled over a million US dollars in savings for Liberia’s government in a recent purchase of high-resolution satellite imagery. These funds can now be used to make other critical investments that modernise Liberia’s geospatial capabilities for census and national population data systems.
A population and housing census is among the most complex and massive peacetime exercises a nation can undertake. It requires careful planning, resourcing and implementation. Ensuring a modern and accurate census process increases data collection efficiency and reduces costs..
High-resolution satellite imagery is a vital data source and one of the key components of census modernisation, but purchasing the images is generally expensive. Within the space industry, the field of Earth Observation represents 14% of the total market, and governments account for a significant number of clients.
Imagery data is crucial to obtaining a comprehensive “birds eye” view of a given territory which, in conjunction with other data, allows decision makers to develop policies and improve infrastructure and access to vital services.
The important data is expensive, and funding is not always easy to secure, especially for countries that have to face financial hardship. Despite the price tag, access is indispensable. Aerial photography and high-resolution satellite imagery provide essential information to support census activities. Satellite imagery is especially useful for census cartography and can also aid the deployment of enumerators when satellite imagery maps complement or replace traditional vector map data loaded onto data collection tablets or in printed form.
While preparing for a census, satellite imagery can be used to update base maps and to capture and identify different land-use and land cover classes, and other geographic features. These products are then used by census cartography teams to optimise their field operations and logistical planning, leading to cost savings and ensuring that most settlements and buildings can be reached.
In the field, satellite imagery can help cartographers navigate built up areas, validate settlements, capture household and building information, and delineate enumeration areas (using the GPS enabled mobile tablets and their built-in applications). Supervisors, controllers, and back office teams also rely on satellite imagery to monitor field work and engage in quality control, making sure that no building is uncounted. While high-resolution satellite imagery can be expensive, it is an indispensable tool to modernise census cartography.
In addition to its role in the census process, satellite imagery can be used by governments for a variety of purposes, including producing or updating cadastral maps, spatial planning and territory development, land-use mapping, and household or enterprise surveys that track changes between urban and rural areas. Imagery is also fundamental to monitoring coastal changes, flooding, desert encroachment, and disaster response. The versatile use of satellite imagery is made possible by the fact that the negotiated license for the imagery allows data sharing across multiple government entities in the country.
To ensure Liberia’s access to important imagery, GRID3 through UNFPA, utilised a UN system contract to purchase satellite imagery at a fraction of its market price. GRID3 then bundled satellite imagery mosaic data packages for Zambia and South Sudan with the additional purchases for Liberia creating a collaborative cross-border approach that encompassed more than one million square kilometres of imagery to unlock an additional significant discount for Liberia.
According to Professor Francis Fonanyeneh Wreh, Director-General of the Liberia Institute of Statistics and Geo-Information Services (LISGIS),
“Access to satellite imagery is paramount for us to be able to ensure that we can prepare and conduct our census in a timely and efficient manner. We thank GRID3 for the role they played in facilitating the acquisition of these crucial data.”
Professor Wreh added that
“the collaborative initiative yielded an unprecedented milestone towards the acquisition of the high-resolution satellite imagery (HRS) of 30 cm for major urban areas in Liberia and 50 cm for the entire country. This was never thought possible compared to the available spatial data used for the 2008 census, and places Liberia amongst the league of first few African nations to execute census mapping with the use of HRS covering the entire landscape of the country.”
During a year when the spread of COVID-19 has forced many governments to divert funding away from geospatial data related efforts and towards crisis response on the ground, the case for purchasing satellite imagery can be challenging to make. Not investing in satellite imagery, however, would hinder a country like Liberia, which needs the data to prepare and execute their census set to take place in December 2021, achieve increased accuracy, and conduct successful post-enumeration analyses with even less time to prepare than normal.
Lorant Czaran, head of the GRID3 team at UNFPA, explains:
“We are learning in our interactions with National Statistical Offices (NSOs) that satellite imagery is becoming more and more essential for census preparations. It is also helping to reduce the time it takes to conduct cartographic activities and identify every structure on the ground. During the current pandemic, time available to many countries preparing for the census is even tighter, and imagery can efficiently help to lower the risk of delays or postponement.”
The discounted purchase of satellite imagery in support of the Liberian government is just a beginning. The partnership plans to continue to advise and assist NSOs and other government partners to ensure that they will be able to acquire satellite imagery at affordable prices, which will enable the modernisation of national statistical ecosystems and improve surveys, censuses, and other methods of geospatial data collection in the future.