1 of 18

Unlocking the promise of Tomorrow�

Edward Boamah

Technical Manager

2 of 18

Agenda

Introduction - DE Africa
DE Africa Datasets/Services, Platforms
Use Cases and diversity
Questions and Open Discussion

Digital Earth Africa

2

3 of 18

01

What is Digital Earth Africa?

3

4 of 18

What is Digital Earth Africa?

Guiding Principle: Diversity and inclusion

Our platform and services provide free, open and accessible analysis ready satellite data.

Our users, including African governments, industry and decision makers can use the Digital Earth Africa Map and Sandbox to track changes across the continent in unprecedented detail. This provides valuable insights for better decision making across many areas, including:

Flooding
Drought
Soil and coastal erosion
Agriculture
Forest cover
Land use and land cover change
Water availability and quality
Changes to human settlements

Gender equality today for a sustainable tomorrow

5 of 18

5

Eye of Sahara: Credit: Contains modified Copernicus Sentinel data 2021, processed by Digital Earth Africa.

Coastal erosion

Urbanisation

Agriculture and food security

Water resources and flood risks

Land degradation

Our Vision

DE Africa will provide a routine, reliable and operational service, using Earth observations to deliver decision-ready products enabling policy makers, scientists, the private sector and civil society to address social, environmental and economic changes on the continent and develop an ecosystem for innovation across sectors.

Digital Earth Africa works to improve the lives of people across the African continent by translating Earth observations into insights that will support sustainable water management, agricultural practice, food security and urbanisation.

We make Earth observation (EO) data readily available, delivering decision-ready products to the African continent.

With free and rapid access to the data they need, policy-makers, scientists, the private sector and civil society can innovate to address social, environmental and economic changes across the continent and respond effectively to the challenges of sustainable development.

Data generated by Digital Earth Africa will provide valuable insights for better decision making across many areas, including:

Land degradation

coastal erosion

urbanisation

water resources and flood risks

agriculture and food security

Image: Eye of Africa - in the Sahara desert of west–central Mauritania, Northwest Africa. This is a dome of rock about 40 km across, the top of which has been eroded through time to reveal its internal layers - which appear a concentric ‘onion’ rings

6 of 18

Added value of satellite data and products available through Digital Earth Africa

Space agencies

Find out more technical detail in Digital Earth Africa Docs

p

Study of the coast of Tanzania with GeoMAD, 2019, RGB

Crop monitoring in Egypt 2001-2020, Landsat, RGB

Mount Nyiragongo monitoring, 2018 Sentinel-2 RGB and 2021 Sentinel-1

Measuring water extent on rangelands in Etosha National Park, Namibia 1992-2021, Landsat, False Color

Analysis ready Data

Free access, even for commercial purposes, to 3.1 petabyte of optical and radar data captured by 7 satellite missions, centralised on the African continent, at Cape Town AWS Hub
Analysis-ready data optimised for remote research, discovery and analysis, updated regularly. no need to download data.
Continental derivative services ready for decision-making and adapted to the challenges of Africa, for monitoring water, land and the coastline
Full visibility into the generation of continental services
Data available through interactive or programmatic interfaces in French and English, or via GIS software
Complex analyses on a specific topic supported by a large library of open source SDG-oriented tools
A large network of institutional partners in Africa and experts allowing capacity building and the dissemination and use of services
Free learning and support platforms in FR and ENG

STAC

7 of 18

DE Africa is diverse and inclusive

DE Africa will seek to be an exemplar of diversity and inclusiveness. The governance framework will be mindful particularly of gender and geographic diversity in its makeup at all levels.

DE Africa Governance Framework, 2019

Guiding Principle: Diversity and inclusion

DE Africa is committed to ensuring our work promotes geographic and language diversity across the African continent, gender equality, and inclusion of youth and people with disabilities.

8 of 18

Who are we working with?

8

South African National Space Agency
Regional Centre for Mapping for Resource Development (RCMRD), Kenya
AGRHYMET Regional Centre, Niger
African Regional Institute for Geospatial Science and Technology (AFRIGIST), Nigeria
Centre de Suivi Ecologique (CSE), Senegal
Observatoire du Sahara et du Sahel (OSS), Tunisia
AfriGEO

Digital Earth Africa is working with Partners across Africa:

9 of 18

02

Datasets, services and platforms

10 of 18

DE Africa Dataset and Services

10

Geomedian annual images provide seamless, cloud-free coverage over the whole continent, useful for characterising landscape changes, monitoring crops, etc.
Median Absolute Deviation to characterise and measure change in the landscape. This service can be used in machine learning for change detection, land cover mapping, and environmental monitoring. Detecting seasonal variation supplements long-term decision-making by policy makers and industry with short-term, cyclical environmental management considerations.
Water Observations from Space (WOfS) allows users to understand the location and movement of water present in a landscape. This product can be used for environmental monitoring, flood mapping, monitoring planned water releases, and management of water resources in highly regulated systems.
Food Security - cropland extent map identifies areas that have been cropped in a given year. A consistent, up-to-date cropland extent map for the continent would assist in implementing the GEOGLAM crop monitor program.
Seasonal fractional cover allows users to understand large scale patterns and trends and inform evidence based decision making and policy on topics including wind and water erosion risk, soil carbon dynamics, land surface process monitoring, land management practices, vegetation studies, fuel load estimation, ecosystem modelling and rangeland condition.
NDVI anomalies - demonstrating monthly anomalies going back to 1980s using the Landsat archive to allow effective monitoring of seasonal and long-term changes in cropping patterns across the African continent, allowing farm-level action.

Geomedian

Crop mask

WOfS

11 of 18

Crop Mask

11

Crop Land a piece of land of minimum 0.01 ha (a single 10m x 10m pixel) that is sowed/planted and harvestable at least once within the 12 months after the sowing/planting date.

This definition will exclude non-planted grazing lands and perennial crops which can be difficult for satellite imagery to differentiate from natural vegetation.

Overall accuracy 83% - 94%

https://docs.digitalearthafrica.org/en/latest/data_specs/Cropland_extent_specs.html

12 of 18

Crop Mask – Datasets

12

In total, around >25,000 training samples

1,800 validation samples were collected

Random Forest Algorithm was used

The model is online, and can be used for other types of classification

13 of 18

Crop Mask

13

14 of 18

Crop Mask – Ghana

14

Stats

~28012.1475km² or 2801214.75 hectare

~12% of the country land are crop land

15 of 18

Measuring crop health/Mesurer la santé des cultures

Crop_health.ipynb

15

Study area: Croplands, Senegal

lat = 14.789064

lon = -17.065202

buffer = 0.005

date = '2020-08-01'

16 of 18

Measuring vegetation phenology

Phenology_optical.ipynb

16

Steps:

Calculate phenology statistics using xr_phenology

DE Africa function xr_phenology can calculate a number of land-surface phenology statistics that together describe the characteristics of a plant's lifecycle.

17 of 18

Acknowledgements

Digital Earth Africa –

17

18 of 18

Thank you Merci obrigada

Edward Boamah

Technical Manager

Digital Earth Africa

edward.boamah@digitalearthafrica.org

Jërëjëf. Kea leboga. meda wo ase

Asante. E ṣeun. Murakoze.

Amesegnalaw. Weebale.