ABSTRACT Mountain glacier moraine sequences and their chronologies allow us to evaluate the timing and climate conditions that underpin changes in the equilibrium line altitudes (ELAs), which can provide valuable information on the paleoclimatology of understudied regions such as tropical East Africa. However, moraine sequences are inherently discontinuous, and the precise climate conditions that they represent can be ambiguous due to the sensitivity of mountain glaciers to temperature, precipitation, and other environmental variables. Here, we used a two-dimensional (2-D) ice-flow and mass-balance model to simulate glacier extents and ELAs in the Rwenzori Mountains in East Africa over the past 31,000 yr (31 k.y.), including the Last Glacial Maximum (LGM), late glacial period, and the Holocene Epoch. We drove the glacier model with two independent, continuous temperature reconstructions to simulate possible glacier length changes through time. Model input paleoclimate values came from branched glycerol dialkyl glycerol tetraether (brGDGT) temperature reconstructions from alpine lakes on Mount Kenya for the last ~31 k.y., and precipitation reconstructions for the LGM came from various East African locations. We then compared the simulated fluctuations with the positions and ages (where known) of the Rwenzori moraines. The simulated glacier extents reached within 1.1 km of the dated LGM moraines in one valley (93% of the full LGM extent) when forced by the brGDGT temperature reconstructions (maximum cooling of 6.1 °C) and a decrease in precipitation (−10% than modern amounts). These simulations suggest that the Rwenzori glaciers required a cooling of at least 6.1 °C to reach the dated LGM moraines. Based on the model output, we predict an age of 12–11 ka for moraines located halfway between the LGM and modern glacier extents. We also predict ice-free conditions in the Rwenzori Mountains for most of the early to middle Holocene, followed by a late Holocene glacier readvance within the last 2000 yr.

The long-term success of water projects in water-stressed communities hinges not only on providing access to safe water, but also on equipping communities for sustainable resource management. Coupling research with education facilitates sustainability by growing local hydrogeologic knowledge and supporting prudent management. Adjusting management practices requires time, and it is helped through collaboration and trust between researchers and stakeholders. Research and education were integrated during an evaluation of groundwater resource sustainability and wastewater management practices at Restoration Gateway, an orphanage in northern Uganda. Basic hydrogeologic understanding was established through field work, staff interviews, and literature. An opportunity to collaborate with a visiting surveying and master planning team leveraged time spent on-site for greater results. Hydrologic education occurred formally and informally, through science lessons at the orphanage school and daily interactions with the Restoration Gateway population. Staff were interviewed regarding as-built designs, water usage, and wastewater management practices. Knowledge gained enabled researchers to make recommendations for preserving groundwater quantity and quality. Site-specific information was incorporated into a master plan for future development. Education efforts and trust gained through immersion in the life of Restoration Gateway increased awareness and acceptance regarding groundwater sustainability. In international work, it can be easy to focus on maximizing time for research and associated tasks. This case study presents ideas for spending time in local participation and education. Participation in the local community, involving them in research efforts, and building their hydrogeologic understanding improve the chances of recommendations being adopted and can foster long-term partnerships that enhance groundwater sustainability.

Significant impacts on cave microclimate from large populations of the bat Rousettus aegyptiacus have been documented in three simple caves in pyroclastic rock of Mount Elgon National Park, Kenya, one of which, Kitum Cave, with few bats, acts as a control, indicating microclimatic variations in the absence of significant biological activity. Seven days of temperature logger records, and on-site mapping of rock and air temperature, humidity, and air flow provide the basis for modeling of heat, water, and CO 2 production and dispersion. Internal temperatures in the presence of bats in Mackingeny Cave and Ngwarisha Cave rise to ~18 °C above ambient (from ~12 °C to ~30 °C), but in the control site by only ~2 °C. Excess bat-generated energy is dissipated by conduction to rock and by ongoing air circulation, the strongest of which accompanies bat entry and exit flights. In Kitum Cave, temperatures that are substantially lower than bat thermo-neutral zone raise concern for Allee effects on long-term colony fitness: Modeling indicates that a population of at least 100,000 bats should promote colony vitality. Metabolic outputs were modeled to yield corrosional potential: At these population densities, were the caves in limestone, rates of surface denudation caused directly by metabolic outputs would be 1 m in ~80,000 yr. These results confirm that tropical bats can be effective niche constructionists, by optimizing microclimatic roost conditions, by longer-term bioerosional optimization of rock surfaces for roosting, and by long-term niche engineering through zoo-speleogenetic enlargement of roost volume.

Abstract The Volcano Sensor Web (VSW) is a globe-spanning net of sensors and applications for detecting volcanic activity. Alerts from the VSW are used to trigger observations from space using the Earth Observing-1 ( EO-1 ) spacecraft. Onboard EO-1 is the Autonomous Sciencecraft Experiment (ASE) advanced autonomy software. Using ASE has streamlined spacecraft operations and has enabled the rapid delivery of high-level products to end-users. The entire process, from initial alert to product delivery, is autonomous. This facility is of great value as a rapid response is vital during a volcanic crisis. ASE consists of three parts: (1) Science Data Classifiers, which process EO-1 Hyperion data to identify anomalous thermal signals; (2) a Spacecraft Command Language; and (3) the Continuous Activity Scheduling Planning Execution and Replanning (CASPER) software that plans and replans activities, including downlinks, based on available resources and operational constraints. For each eruption detected, thermal emission maps and estimates of eruption parameters are posted to a website at the Jet Propulsion Laboratory, California Institute of Technology, in Pasadena, CA. Selected products are emailed to end-users. The VSW uses software agents to detect volcanic activity alerts generated from a wide variety of sources on the ground and in space, and can also be easily triggered manually.

Abstract DOWNFLOW is a probabilistic code for the simulation of the area covered by lava flows. This code has been used extensively for several basaltic volcanoes in the last decade, and a review of some applications is presented. DOWNFLOW is based on the simple principle that a lava flow tends to follow the steepest descent path downhill from the vent. DOWNFLOW computes the area possibly inundated by lava flows by deriving a number, N , of steepest descent paths, each path being calculated over a randomly perturbed topography. The perturbation is applied at each point of the topography, and ranges within the interval ±Δ h . N and Δ h are the two basic parameters of the code. The expected flow length is constrained by statistical weighting based on the past activity of the volcano. The strength of the code is that: (i) only limited volcanological knowledge is necessary to apply the code at a given volcano; (ii) there are only two (easily tunable) input parameters; and (iii) computational requirements are very low. However, DOWNFLOW does not provide the progression of the lava emplacement over time. The use of DOWNFLOW is ideal when a large number of simulations are necessary: for example, to compile maps for hazard and risk-assessment purposes.

Abstract Geochemical data from drill cuttings of a 3,392 m deep well drilled on the shores of Lake Albert-Uganda, East Africa were used to investigate a longterm paleoenvironmental history of the Lake Albert rift basin-Uganda. The Ngassa-2 well was drilled through loose and coarse-grained sands in the upper section, massive mudstone deposits interbedded with siltstones in the middle sedimentary section, and a thin conglomerate at the base. Statistical treatment of data by using Principal Component Analysis shows that Fe, Ti and Rb (silicate mineral elements) account for much of the variability in the data, with about 40% of the total variance compared to 20% for total organic carbon (TOC) and Si (organic and quartz). Results from XRF data and TOC are indicative of warm and wet conditions around the late Miocene, later developing into cooler and dryer climatic conditions around the late Pliocene. Anoxic lacustrine conditions in the early Pliocene are documented by a dramatic rise in TOC and coinciding trends with iron for the depth interval 3,000–3,250 m. Lithological observations, seismic data attributes, and down-hole gamma ray logs provide evidence of a basin that transitioned from fluvial to mixed fluvial-lacustrine and subsequently dominantly lacustrine environment before shifting back to fluvial and shallow lacustrine system in the late Pleistocene and Holocene.

Abstract The project area is the onshore Ugandan Lake Edward-George basin, Albertine rift that is located in the northernmost part of the western arm of East African Rift System (EARS). Dominion Petroleum Ltd carried out petroleum exploration in the Lake Edward basin; i.e. , field geological mapping, seismic data acquisition, and interpretation, etc. This resulted in the drilling of the Ngaji-1 well, the only deep well in the entire area. The major aspects of this research are: (1) to evaluate the sedimentology and stratigraphy of different lithologies in this area using ‘lithofacies’ or ‘lithofacies associations,’ (2) revisit the lithostratigraphic framework of this area, and (3) determine how climate and tectonism have influenced sedimentation style, with the major emphasis on further unravelling the petroleum potential of the area. XRF and clay mineralogy (XRD) studies proved to be of little significance in the paleoclimatic interpretations of sediments within the study area, Lake Edward basin and therefore only ICP-MS/OES data has been used in this project. From field geology and geochemical data (ICP-MS/OES), it is confirmed that climate and tectonism played a significant role during sedimentation in this basin. It has been found that all scenarios raised in the predictive coupled climatic-tectonic model are present within the Lake Edward-George basin. Results from this research however also show that rift-fill sediments in the south and eastern Lake Edward-George basin (close to the rift shoulders) are strongly dominated by fluvial and alluvial distributary fan complexes, and within these fan complexes, could be recognized and described during detailed stratigraphic logging the different lacustrine packages encountered within the basin-fill sediments close to the present-day Lake Edward. Sediments within the study area were identified and classified into four members: (1) Kabagwe, (2) Rushaya, (3) Kiruruma, and (4) Kisenyi members. However, as in previous research work within the area, the main challenge was to locate the definitive chronostratigraphic markers for these members. It has been further confirmed that sediments in the Lake Edward-George basin represent a petroleum play for hydrocarbon generation and accumulation, in which the necessary elements of a valid petroleum system were identified; i.e. , there was excellent or good potential for reservoirs and top seals as well as circumstantial evidence of regionally source rocks, possible seals, traps and hydrocarbon migration pathways.