Abstract:
This study investigated spatial and temporal
trends of rainfall and temperature in the Amboseli ecosystem of
Kenya. The analysis were based on historical Climate Hazards
group InfraRed Precipitation with Station (CHIRPs) and
Climate Hazards group InfraRed Temperature with Station
(CHIRTs) data for the period 1960-2014 and the period
2006-2100 for the projections. This data was used due to
limitations in the observed station data. Projections of rainfall
and temperature were based on Regional Climate Models
(RCM) from Coordinated Regional Downscaling Experiment
(CORDEX) over the Amboseli ecosystem. The long-term annual
and seasonal trends of rainfall and temperature were analyzed
via Mann– Kendall’s statistical test and linear trend analysis.
The annual and seasonal rainfall declined slightly between 1960
and 2014 though not significant. However the temperatures
increased more in the annual minimum (1.23 °C) compared to
the annual maximum (0.79 °C). The maximum temperatures for
the October-November-December (OND) season had highest
increases of 0.88 °C while the March-April-May (MAM) season
showed an increase of 0.69 °C. The highest increase in minimum
temperatures of 1.35 °C was recorded for the
June-July-August-September season (JJAS), while the least
increase was in MAM (1.04°C). Projected rainfall based on
Representative Concentration Pathways (RCPs) for the periods
2006-2100 varied with RCP 2.6 showing a decline for the four
seasons. RCP 4.5 and 8.5 project marginal increase in annual
and OND with declines in the MAM and JJAS. Projected
maximum and minimum temperature for RCP 2.6 indicate
increments of less than 1 °C while for RCP 4.5 the maximum
range is between 0.57 °C and 1.85 °Cand minimum is between
0.51 °C to 1.98 °C. RCP 8.5 projected maximum increase are the
highest between 1.11°C and 4.34 °C and minimum is between
1.34 °C and 5.26 °C based on period – 2030, 2050 and 2070. The
increase of temperatures and changes in rainfall can have large
impacts on the resources in the savanna dry lands of East Africa
especially on its livestock, agriculture, wildlife and pastoral and
agro-pastoral communities.
Index Terms— Climate change, dry lands, mitigation,
Representative Concentration Pathways, temperature and
rainfall.
