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Forest landscape management for climate
change resilience in West and Central Africa
L. V. Verchot, K. Fernandes, D.J. Sonwa, W. Baethgen, and
Our Common Future, Paris, July 2015
Cameroon Policy responses
• Forest-Environment Sector Programme document
(FESP) does not mention CC
• 1st communication to the UNFCCC deals with sustainable
forest management, but proposes no changes to meet
• Poverty reduction strategy paper (PRSP) does not
Why climate adaptation is poorly reflected in
national development planning documents
• Poor data on adaptation options
• Limited awareness of adaptation among
stakeholders and the population
• Low staff capacity for planning, monitoring and
• Lack of mechanisms for information sharing and
management across sectors
• Inadequate institutional capacity
• Lack of commitment and incentives to enforce forest
• Lack of information about climate patterns
The PERSIANN dataset has the advantage of extending back to 1983
and is ¼ degree resolution. Combines satellite and gauge information.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Central Africa domain Climatology from PERSIANN
in Central Africa
JJA trends of TRMM precipitation (left) and PERSIANN
precipitation (right). Period 2000-2014.
JJA trends in EVI (left), VHI (right).
Vegetation indices (above)
indicate a decrease in
greenness since 2000.
The precipitation trends (left)
are much more modest and
Correlation between the vegetation indices (columns) and precipitation datasets
(rows) for JJA. The correlations are calculated for the common period 2000-2014,
constrained by EVI availability.
As reported in Zhou 2014,
the correlations between
and Veg. indices are not
high over the rainforest.
between VHI and
precipitation seem to
perform better than EVI.
The areas over the
rainforest show a poorer
relationship perhaps due
Changes in the northern sector are minimal, as JJA vegetation would respond to
concurrent wet season precipitation (JJA) as previous months are very dry towards
JJA: dry season in
southern sector of the
Rainforest core is never
with a longer period
(MAMJJA), especially in
Cumulative effect of
precipitation over a 6
mo. is more relevant to
veg response during
The point of the last 4 slides is to establish that
TRMM and PERSIANN data are consistent and that
trends found in TRMM can be found in PERSIANN.
We want to use PERSIANN to see if the trends
extend further back in time than what Zhou et al.
Correlation between JJA VHI and PERSIANN MAMJJA precipitation
(a). Trends in VHI (b), PERSIANN JJA precipitation (c) and MAMJJA
precipitation (d) for the period 1985-2014.
Message: Long time-series are needed for trend analysis. The
shorter period shown previously (2000-2014) shows decrease in
vegetation indices and no consistent precipitation trend, whereas a
longer time series show less significant vegetation trends, but
better agreement with precipitation trends in the northern sector.
MAMJJA precipitation trends. (a) PERSIANN 1985-2014, (b) GPCC 1985-
2014 and, (c) GPCC 1955-1984. Unit: mm/month per year.
(a) (b) (c)
The plot (a) is the same as figure (d) in the previous slide. Plot b is for the
same period, but the dataset is GPCC rain gauge only data. The spatial
distribution of trends are consistent: patches of positive trends in the Sahel
and negative in Central Africa. Plot (c) is GPCC MAMJJA trends but for last
30 years, showing opposite Sahelian trend.
MAMJJA SPI Trends 1955-1984 MAMJJA SPI Trends 1985-2014
Top: Same plots (b) and (c) from previous slide. Bottom: Bar plot is
MAMJJA SPI calculated for the domain marked with a box in the map
Equatorial (western) Africa
Equatorial Africa for the
purpose of this analysis is the
area 5S-5N and 8E-30E.
Monthly mean precipitation for the domain 5S-5N and 8E-30E.
Precipitation in the Congo follows a bimodal pattern with dry
seasons (JJA and DJF) and 2 wet seasons (MAM and SON).
The trends shown
are 90% significant.
Units are mm/month
Note the marked
negative trend in
MAM and DJF that
reflect in the annual
Timescales of variability- Domain 5S-
Annual precipitation anomalies (mm/month). Note the
predominance of dry years beginning in the 1970s and only
recently recovering (with a vengeance)