Dramatic change in local climate patterns in the Amboseli basin, Kenya

Abstract

The Amboseli basin, a semi-arid, open savannah area of southern Kenya, has experienced extensive changes in habitat since the early 1960's. The present report documents patterns of air temperature and rainfall in Amboseli for the 25-year period beginning 1976. Daily temperatures increased dramatically throughout this time period, at a rate almost an order of magnitude greater than that attributed to global warming. Mean daily maximum temperature increased more than did daily minimum (0.275 vs. 0.071 8C per annum). Although increases in mean daily maxima were documented for all months of the year, they were greatest during the hottest months, February and March. Annual rainfall varied more than four-fold (x 346.5 mm, SD 120.0, range 132.0^553.4 mm), yet did not exhibit any directional or other regular pattern of variability among years over this same 25-year period. Empirical as well as theoretical investigation of relations between such changes in climatic conditions and habitat characteristics are needed at local and regional as well as global scales.

Glacier loss on Kilimanjaro continues unabated

“…A 25-year temperature and precipitation history recorded in the Amboseli Basin, a few kilometers from the northern base of Mount Kilimanjaro, reveals a warming trend in both maximum and minimum temperatures and large interannual variability in precipitation but no long-term trend (11). Altmann et al (11) note that the weather and water availability at Amboseli are highly affected by conditions on the mountain. Over recent decades there has been a continual transformation of the landscape surrounding Kilimanjaro into agricultural land, thus, unraveling large-scale climate forcing from regional forcing caused in part by landscape changes is difficult.…”

Coping with a challenging environment: Effects of seasonal variability and reproductive status on glucocorticoid concentrations of female baboons (Papio cynocephalus)

“…Over the several decades of the Baboon Project research, annual rainfall in Amboseli has varied from 150 mm to more than 550 mm but with no trend or predictability (Alberts et al, 2005;Altmann et al, 2002). In contrast, both average maximum and minimum daily temperatures gradually increased from the 1970s through the early to mid 1990's .…”

“…February and March are particularly hot; on average across the 4 years of the present study, for 63% of the days in February and 74% of those in March the weather station T max was at least 34°C, a temperature that is close to baboons' normal core body temperature of 38°C. In some years Amboseli experiences an 'inter-rain' season of lower rainfall during the January through March period (Struhsaker, 1967;Altmann et al, 2002), especially so during drought years. In such years, environmental stressors may resemble to some extent those in October at the end of normal dry season.…”

“…Monthly and seasonal patterns of (a) T min , T max and rainfall, (b) proportion of time spent feeding and resting, and (c) fGC. Months are ordered according to 'hydological year', beginning with November, the first month of the wet season (as in, e.g., Altmann et al, 2002). (a), each monthly value of T min , T max and cumulative rainfall represents a mean (± SE) across the 4 years of this study (2002)(2003)(2004)(2005) Comparison of (a) fGC levels, (b) feeding and (c) resting behavior of females for whom data were available in the same reproductive state during both the wet and the dry season.…”

Beyond ritual and economics: Maasai lion hunting and conservation politics

“…Rainfall is spatially and temporally variable, with averages of , 650 mm year −1 and concentrated in NovemberDecember and March-May (Prins & Loth, 1988;Altmann et al, 2002). In the dry season wildlife cluster around permanent water sources inside national parks.…”