Monitoring and quantifying the impact of forest degradation associated
to charcoal production in sub Saharan Africa through the integration of
medium, high and very high-resolution remote sensing data and
field-based information
Abstract
Urban population in sub Saharan Africa (SSA) is rapidly growing. While
only 30% of its population lived in urban centers in 2000, this figure
will reach 60% by year 2050. Urban energy demand is closely tied to
forest degradation. Charcoal is the main source of cooking fuel for
eighty percent of African urban households and its overall consumption
is expected to rise by 2040. Charcoal production is already the main
driver of forest degradation in SSA. REDD+ guidelines encourage
countries to identify and describe individual activities and drivers
causing forest degradation as an initial step to define suitable methods
for measuring and monitoring and formulate appropriate strategies and
policies. Yet, forest degradation associated to charcoal production
remains largely under reported. Charcoal production results in partial
removals of forest cover that do not necessarily involve significant
variations of the spectral signal. As a consequence, efforts to monitor
forest degradation associated to charcoal production with medium
resolution data has proved elusive. We present initial results of our
effort to monitor and quantify carbon emissions from forest degradation
due to charcoal production in SSA. Our work combines time series of
multi sensor medium (20 – 30m), high (2m) and very high (0.5m) spatial
resolution sensors with field data to characterize the spatial and
temporal dynamics of charcoal production in charcoal production sites
across SSA. The integration of these datasets provides the means to map,
monitor and measure charcoal kilns, and subsequently quantify the
magnitude and intensity of aboveground biomass removals associated to
charcoal production at a level of detail and precision not reported
previously. Our initial results reveal that charcoal production accounts
for a larger share of greenhouse gas emission than previously reported,
highlight its negative impacts on the ecosystem, and question the
long-term sustainability of charcoal production under current and future
urban energy demands. This work is a first step towards the development
of a monitoring, reporting and verification system specific to forest
degradation in the SSA context.