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Water 2016, 8(12), 572; https://doi.org/10.3390/w8120572
Water Balance and Level Change of Lake Babati, Tanzania: Sensitivity to Hydroclimatic Forcings
Department of Physical Geography, and the Bolin Centre for Climate Research, Stockholm University, SE-106 91 Stockholm, Sweden
Department of Urban and Rural Development, Swedish University of Agricultural Sciences, Box 7012, SE-750 07 Uppsala, Sweden
Department of Earth Sciences, Uppsala University, SE-752 36 Uppsala, Sweden
Author to whom correspondence should be addressed.
Academic Editor: Karl-Erich Lindenschmidt
Received: 29 September 2016 / Accepted: 28 November 2016 / Published: 5 December 2016
We develop and present a novel integrated water balance model that accounts for lake water—groundwater interactions, and apply it to the semi-closed freshwater Lake Babati system, Northern Tanzania, East Africa. The model was calibrated and used to evaluate the lake level sensitivity to changes in key hydro-climatic variables such as temperature, precipitation, humidity and cloudiness. The lake response to the Coupled Model Intercomparison Project, Phase 5 (CMIP5) output on possible future climate outcomes was evaluated, an essential basis in understanding future water security and flooding risk in the region. Results show high lake level sensitivity to cloudiness. Increased focus on cloud fraction measurement and interpretation could likely improve projections of lake levels and surface water availability. Modelled divergent results on the future (21st century) development of Lake Babati can be explained by the precipitation output variability of CMIP5 models being comparable to the precipitation change needed to drive the water balance model from lake dry-out to overflow; this condition is likely shared with many other East African lake systems. The developed methodology could be useful in investigations on change-driving processes in complex climate—drainage basin—lake systems, which are needed to support sustainable water resource planning in data scarce tropical Africa.
Keywords:Lake Babati; water balance; lake level sensitivity; cloudiness; hydroclimatic forcings; East Africa
1. Introduction
Hydrological modeling of lake systems enhances our understanding of important processes controlling lake dynamics. It also allows for quantified assessment of the impacts of future climatic and anthropogenic changes on water availability and of the functioning of aquatic ecosystems. East African lakes have long been the subject of many hydrological modeling studies, mainly for the purpose of estimating their water budgets and their sensitivity to climatic forcings. Examples include the modeling of Lake Victoria's water balance with specific emphasis on the evolution of its water storage and the impacts of climatic changes and human management on the lake outflow [1,2,3]; modeling of water level fluctuations and estimation of surface evaporation at the shallow Lake Ziway (Ethiopia) [4]; assessing the sensitivity of Lake Tana (Ethiopia) to changes in rainfall [5]; and modeling the water balance of Lake Manyara (Tanzania) [6]. Hydrological modeling studies of lakes in the East African region have also aimed at improving the reconstruction of paleoclimatic conditions inferred from climate proxies such as fossil pollen and diatoms in lake sediments. For example, modeling the paleo-lake levels of Lake Naivasha and mega-lake Suguta (Kenya) allowed the validation of estimates of paleo-precipitation in East Africa [7,8].
Many of these lake-centric hydrological modelling studies have involved isolating the lake body from its surrounding catchment area; whereby catchment inputs are estimated independently and fed into the lake model. For example, [9] coupled their Lake Abiyata (Ethiopia) water balance model with surface inflow calculated using a catchment runoff model and applied groundwater fluxes estimated with a numerical groundwater flow model. Drawbacks of this de-coupled approach are that lake interactions with catchment processes and conditions, such as lake level—groundwater level interactions, are neglected, and that uncertainties inherent in various methods of estimating these internal fluxes are transferred into the lake model. Such uncertainties can make closing the water balance difficult, leading to relatively large discrepancies of the lake water balance [6]. In addition, these uncertainties can compound into an unrealistic calibration of model parameters or other water balance components.
Another challenge to the successful modelling of lake systems is the difficulty to reasonably estimate lake evaporation, which is often the largest component of lake water budget [7]. Indeed, lake evaporation cannot be easily measured and its calculation requires large amounts of location-specific data, which is typically not available in most remote areas of Africa or is only available through regional-scale databases (i.e., [10]). For example, lake surface evaporation can be sensitive to changes in cloudiness [3,11] but many lake modelling studies in the region have rarely considered this parameter in their estimates. Further, since lake systems, especially closed ones, tend to be dynamic over the course of the year and between years, they are particularly sensitive to climatic forcings both over the lake and within the surrounding catchment (e.g., [12]). While many of the available studies have been able to assess the sensitivity of lake systems to climatic changes, this is typically done to constrain parameter uncertainties and their contributions to model predictions. However, there is little documentation (e.g., [2]) of studies on future lake system changes based on actual projections from global circulation models in the region.
In this study, we present a novel water balance model of the semi-closed fresh water Lake Babati, Northern Tanzania. The lake supplies water to meet the various needs of the about one hundred thousand citizens in Babati town [13] and supports a diverse ecosystem, including between seventy and ninety hippos and several species of fish and lake birds [14,15]. Furthermore, like most of the neighbouring lakes [16,17,18,19], Lake Babati could be equally rich in proxy climate data, which is essential for local and regional paleoclimatic studies. A combination of extensive landscape changes in the lake's catchment and recurrent extreme precipitation events over the last century has triggered frequent lake flooding events, inundating Babati town, which is located at the downstream of the lake outlet [20]. The ever-increasing population density around the lake and prospective impacts of regional climate change and variability also pose a serious threat to the sustainability of the lake water resources. Despite its importance, the general hydrology of the lake remains little known. Previous efforts [21] have developed a lumped lake-centric water balance model to simulate the lake levels and flood discharge, based on daily rainfall, surface and groundwater fluxes, groundwater storage and evapotranspiration. The model, however, presented large uncertainties, since the approach did not allow consideration of water balance constraints imposed on the estimated fluxes by the lake catchment.
As such, the water balance model presented in this study is based on a rather novel approach of considering the lake and its catchment together in a truly integrated implementation. This allows highly uncertain fluxes, such as the groundwater discharge into the lake, to be adequately constrained through closure of overall water balances. Together, this coupled groundwater–lake water approach can provide a robust method to estimate lake level and volume changes in a data-scarce setting. With that, the purpose of the study is to evaluate the lake level sensitivity to climatic variables that may change in the future as a result of global climate change, such as temperature, precipitation, humidity and cloudiness, and response to future scenarios of climatic forcings. More generally, such knowledge is essential in assessments of future water security (e.g., surface water availability) and flooding risks.
2. Materials and Methods
2.1. Description of the Study Site
2.1.1. General
Lake Babati is located at approximately 35°45′ E and 4°15′ S about 200 km to the South West of the city of Arusha in northern Tanzania (Figure 1). It is a fresh water lake, with relatively shallow but highly fluctuating water levels [14]. The lake may have been formed following the East African Rift Valley floor uplift that resulted in the creation of both temporary and permanent lakes in the region, including the neighbouring Lake Manyara or Lake Burungi [22].
The lake is located at an altitude of 1345 mean above sea level (m a.s.l.). It has a current average surface area of 7 km2 and its hydrological catchment covers about 355 km2. The ratio of the lake to basin area has increased from 0.013 in 1960 to 0.02 in 1990. The catchment area can be subdivided into two geomorphologically distinct areas: the southern part, consisting of a steep landscape with hills and plateaux formed by Precambrian basement rocks; and the northern part, dominated by a volcanic landscape, where neogene volcanic deposits in the shape of pyroclasts and minor explosion vents and craters form the major features [20]. The area close to the lake is surrounded by wide plains of mbugas—black cotton soils [23] and clear sands. Large sandfans are observed upstream from the mbugas creating a large water infiltration area covering approximately 50 km2. Large-scale gully erosion takes place in the volcanic soils to the North and forms a well-developed drainage system that transports sediments into the alluvial sands and mbugas around the lake. At the northern downstream edge of the lake is Babati town, lying on a volcanic tuff ridge with dark brown soils, which is highly erodible and susceptible to infiltration. Groundwater flow from the lake has been observed through this feature and supports valley cultivation to the east of the town [20].
The lake's catchment has been used as grazing land since at least 2000 years ago [24]. The catchment was mostly dominated by forests, with agriculture occupying a small fraction at the beginning of the twentieth century [21,25], but due to the land management policy implemented in the 1970s, considerable parts of the forest have been converted into farmlands [21]. It has been suggested [26] that while there was still more bushland or woodland than cultivated areas in 1960s, cultivated land doubled the combined bushland and woodlands area in the 1990s.
2.1.2. Hydroclimatic Conditions and Independent Observations of Water Balance Components
The region experiences two rainy seasons between October and May, separated by a short dry spell (January–February), with the rest of the year consisting of a dry season [20,27]. Records from Babati meteorological station between 1973 and 2009 indicate that the area receives an average rainfall of 789 mm per year, with a standard deviation of 278 mm (Figure 2). The data poorly correlates with records of neighbouring stations, such as Galappo Mission (13 km), Mulu (45 km) and Haubi Mission (63 km), indicating a complex spatial distribution of rainfall in the region ([20,21,28]). Previous work [27] suggests that the region is subject to large regional inter-annual variations in rainfall due to the El Niño-Southern Oscillation (ENSO) as well as orographically induced precipitation in the highlands. Rainfall records around the study area indicate that the topographic effect is 3.6 mm/year/100 m, explaining a relatively modest percentage (4%) of total rainy season precipitation between stations. The annual average temperature is 19.4 °C observed over the same period.
Hydrologically, the lake has no natural permanent surface outlet, but following a major flooding event (lake overflow) in 1964, a 4 m3/s capacity artificial outlet connecting the lake to a gully system was constructed to prevent flooding of Babati town ([22,29]). Available lake level records are limited and erratic, covering two periods, i.e., 1978–1984, [25] and 2008–2012 (Internal Drainage Basin Water Office) (Figure 3). The records indicate an average lake depth of 5.27 m and 5.75 m for the first and second period respectively, with a standard deviation of 0.6 m for both periods. These correspond to 1–1.5 m less than the lake overflow level. The water level generally fluctuates about 1 m between the dry and wet season.
The Lake Babati water balance is dominated by lake evaporation and runoff into the lake from the catchment area. Surficial runoff approximates 10% of the total catchment rainfall in the area [21] and can partly be a result of recent catchment deforestation [26,30]. Regional potential evapotranspiration rates near 1300 mm/year [28], but actual evapotranspiration is much lower due to limited available water through precipitation. High lake surface evaporation is a main cause of a positive net lake evaporation depth. Water exchange between the lake and the surrounding groundwater also plays an important role in lake level and salinity moderation. Observations indicate that lake overflow usually occurs some months after the rainfall maxima.
2.2. The Lake Water Balance Model
In this study, we consider a coupled lake-catchment model that consists of three modules: the lake, the adjacent groundwater reservoir and the remaining catchment area. The basis for the modelling is to maintain the water mass balance between input and output over the lake and its catchment area on an annual time step:where and are changes in lake and groundwater storage volumes (L3) respectively; the time step (T). We have assumed that the change of the groundwater volume in the upstream part of the catchment is equal to zero (∆VC = 0). The reason is that ∆VC is expected to be small relative to ∆VL and ∆Vr, since the upstream part of the catchment is located further away from the lake, and will therefore be much less influenced by its (considerable) level variations. P is precipitation (L/T) estimated as being spatially uniform in this study for Lake Babati region from available rainfall records (Figure 2). , and are the surface areas (L2) of the lake, the groundwater reservoir adjacent to the lake, and the remaining upstream part of the catchment, respectively. These were determined from the lake bathymetry and catchment topography (Figure 4). , and are the evaporation over the lake, the actual evapotranspiration over the groundwater reservoir adjacent to the lake and the actual evapotranspiration over the catchment (L/T), respectively. is the groundwater flux (L3/T) draining out of the lake and the possible runoff volume (L3/T) due to lake overflow. These evaporative and water flux components were estimated as described in the following sections.
2.2.1. Catchment Topography and Lake Bathymetry
The area–volume relationship of the Lake Babati was derived from a combination of catchment topographic and lake bathymetric data (Figure 4). Catchment topography is based on a 90 m resolution Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM) ([31]) and paper topographical maps (1:50,000 scale and 50 feet contour spacing) produced by the Directorate of Overseas Surveys for the Tanganyika Government in 1964 from aerial photographs taken in 1958–1960. The paper maps were georeferenced and important features (contours, river channels, lake shore, extent of alluvial deposits) were digitized. Hence, a topo-to-raster interpolation with drainage enforcement [32] within ArcGIS 10.1 spatial analyst package was applied to the digitized contours to generate a hydrologically correct 50 m resolution DEM, based on which (together with the SRTM DEM) the catchment boundary was delineated and its area calculated.
Subsequently, the contour line corresponding to the lake overflow level was used to determine the maximum lake surface area. Then, lake bathymetry was derived by spatial interpolation from lake vertical profile measurements along five transects acquired during a 2010 field visit (Figure 4). From the bathymetric map, the area and volume corresponding to different lake depths (from the lowest point to the maximum lake level, at 1 cm step) were calculated using the "surface volume" tool in ArcGIS 3D analyst. Finally, the area of the groundwater reservoir around the lake was determined based on the extent of the alluvial deposits as digitised from the topographic and geological maps.
2.2.2. Evaporation over the Lake
Lake surface evaporation is one of the main factors controlling the water balance of closed basin lakes. There are several methods to estimate lake surface evaporation, including direct measurements, empirical methods, water budget, energy budget, mass transfer and combination methods [33,34,35,36] or from pan evaporation records [37]. The Penman [35] and the energy balance methods have been extensively applied in the study of East African lakes [3,4,5].
In this study, the energy budget method was adopted. The approach is among the best methods for estimating open water evaporation [38,39,40,41]. Comparatively speaking, the energy budget method is relatively simple and less data intensive [42] and considers the effect of cloud cover, which is often ignored in other methods, despite its large impact on evaporation estimates. The approach is based on the assumption that, under steady-state conditions, the energy gained by the lake water surface from net radiation is compensated by the energy loss through latent and sensible heat transfer, such that:where is the net radiation (W/m2), is the sensible heat flux (W/m2) and the latent heat flux to evaporate water from the lake (W/m2). In our case, it can be assumed that heat exchange between the lake surface and the deeper part of the lake is negligible, since the time step used (one year) is large enough to exclude the influence of diurnal cycles [33].
Equation (2) can be rewritten by introducing the Bowen ratio (B), which represents the fraction of sensible to the latent heat flux, as
The evaporation rate () can be introduced and represents the mass of water that needs to be evaporated to consume the latent heat energy of the latent heat and can be expressed as:where is the latent heat of water vaporisation ().
The net radiation () can be expressed in terms of the net short-wave radiation () and long-wave radiation () as:
Since there were no direct measurements, and were estimated in this study using empirical equations. The net shortwave radiation, which is the radiant flux resulting directly from solar radiation was estimated from [43] as:
being the albedo of the water surface ( [33]) and is the solar radiation at the top of the atmosphere, which is a function of latitude [43]. was estimated to be 416.4 W/m2 at Lake Babati.
The parameter C, the cloud cover, explains the portion of the day during which clouds are not obstructing the sun. C values are highly variable and may have a great influence on lake evaporation estimates. It can be estimated from Equation (8) as:where n and N are actual number of hours of bright sunshine and the number of daylight length, respectively [33]. The optimised value of C after model calibration was 0.4 (see following sections).
The net longwave radiation (), the radiant flux resulting from emissions of the atmospheric gases and the land and water surfaces on earth, was estimated following [44] as:where is the emissivity of water (); is the Stephan–Boltzmann's constant (), Ts is the lake surface temperature (K), and is the saturation vapor pressure (hPa), which can be calculated with Clausius–Clapeyron's relation as:where = 0.622 is the molar mass fraction of water vapour in dry air and is the gas constant of dry air (287 J/kg/K).
The Bowen Ratio (B) is based on the eddy diffusivity hypothesis and is given by the relationship:where Ts and Tr are the temperature (K) at lake surface and at a reference height respectively. An average value of 19.4 °C (292.55 K) for the reference temperature was used. The lake surface water temperature was considered to vary with the air temperature (Ta) by a constant quantity ΔT, using the relation:
This simplification holds, since for such a shallow lake, a low heat storage value in the lake and thus a similar evolution of the air and water temperatures can be expected [4].
and are the specific humidity (%) at a reference height and close to the water surface respectively. The latter is approximated, assuming the near surface air temperature and the water surface temperature are the same and the relative humidity close to the surface is 100% (saturated air) using the relation:where is the saturation vapour pressure (Pa) close to the water surface (Equation (10)); is the atmospheric pressure at the lake surface, calculated by the relation:where = 101,325 Pa is the sea level pressure, g = 9.81 m/s2 is the acceleration of gravity, R = 287 is the gas constant of dry air, is the average catchment temperature, and is the altitude difference between the lake level and sea level. and are the molar masses of water vapour and dry air respectively (g/mol), assuming that the masses of the water vapor and dry air are such that . The optimum value of 50% for relative humidity was determined from model calibration.
2.2.3. Evapotranspiration over the Groundwater Reservoir and the Catchment
Evapotranspiration over the ground is governed by several parameters including (but not necessarily limited to) the amount of water available in the surface layer, atmospheric conditions, the soil hydraulic conductivity of the soil, and plant type. Due to limited information about these variables in the study area, we used the empirical equations by [45,46] to estimate ground evapotranspiration. These relate evapotranspiration with precipitation and ground temperature as:where and are the actual and potential evapotranspiration rate respectively (kg/y/m2 or mm/year), P the precipitation (mm/year), and Tg is average ground surface temperature (K). Since no measurements of catchment temperature were available, Tg was determined relative to the reference temperature at Babati town (1350 m a.s.l.), by assuming the standard atmosphere with a temperature increase of 0.6 K for every 100 m decrease in altitude. Therefore, and in the water balance Equation (1) correspond to the actual evapotranspiration calculated at the mean altitude of the groundwater reservoir adjacent to the lake (1400 m a.s.l.) and at the mean altitude of the remaining upstream part of the catchment (1800 m a.s.l.) respectively, and adjusted by a calibration factor () to account for catchment dependency uncertainties [47], such that:with Ea calculated at 1400 m a.s.l. andwith Ea calculated at 1800 m a.s.l.
The factor Xc was determined through calibration to be 1.15 (see Section 2.3).
2.2.4. Groundwater-Lake Water Interaction
Lake Babati water interaction with the surrounding groundwater reservoir also plays an important role in the water budget. The extent of the groundwater reservoir adjacent to the lake was determined from available topographical and geological information. The lake-groundwater interaction was modelled by assuming the change in groundwater storage depth equals the change in lake level from the net change in volume () after each time step, such that:with being the mean porosity of the aquifer (-).
The groundwater flux leaving the lake () was approximated by a Darcy flow, aswhere is the aquifer horizontal hydraulic conductivity (m/s) and the groundwater gradient (m/m), assumed equal to the topographical slope downstream of the lake. is the cross-sectional area perpendicular to the flow (m2), expressed by the product of the water depth in the lake () and the average width of the downstream edge of the lake. Based on hydrogeological maps showing sandy aquifer conditions in the Lake Babati vicinity [48], the hydraulic conductivity (kh) and porosity () were set accordingly [49,50] to 50 m/day and 40% respectively.
2.3. Model Structure, Input Parameters, Calibration, and Sensitivity
A Fortran-based program was developed to solve the mass balance (Equation (1)) following the calculation workflow in Figure 5. The program first calculates the net water volume change from the combined input (precipitation) and output (evaporation and groundwater leakage) fluxes at the end of a time step (1 year). Then, based on the area–volume relationship, the corresponding lake level change (positive or negative) is determined and used to update the lake level from the previous time step. The procedure is repeated iteratively starting from an initial lake water depth taken from observations until the lake level change between two successive iterations is small enough (<10 mm/year) or the lake has dried out completely. Upon convergence of a solution, the evolution of different water balance components over the simulation period is recorded in a text file for further analysis. The choice of the annual time step was motivated by data availability. Moreover, the annual time step was adequate since the study sought to establish the annual water balance of the lake-catchment system and assess the sensitivity to changes in long-term hydroclimatic conditions, rather than on seasonal dynamics such as in [3,51].
Model parameters (Table 1) were, to a large extent, independently derived from available meteorological, hydrogeological and lake level records, as described in previous sections. However, there were no site-specific data on the cloud cover fraction (C) and the factor for adjusting actual evapotranspiration Equations (17) and (18). Thus, these were determined through calibration, constraining them within physically reasonable parameter ranges derived from parallel studies. From sunshine duration estimates in this world region [28], cloud cover can be expected to be between 0.3 and 0.5. Furthermore, from analyses of different hydroclimatic regions (including tropical, temperate and arid conditions), has been found to range between 0.7 and 1.2 [12,47,52,53,54]. This reflects an error in the estimated evapotranspiration on the order of 20% to 30%, which e.g., is lower than errors of about 50% that were reported in a synthesis of [52]. A possible reason for the relatively low errors is that these studies consider annual or multi-annual averages over catchments, as opposed to short-term, point values which are considerably more difficult to predict.
Considering these bounds (Table 1), the model was run in steady state with several pairs of the two parameters (C, Xc) over the period 1978–1984, resulting in a response surface map (Figure 6) showing the evolution of the deviation between observed and simulated lake level. The parameter combination that gave the least deviation between observed and modelled lake levels during the calibration period was determined as C = 0.4 and Xc = 1.15. A factor contributing to the relatively good closure (i.e., Xc is close to unity) can be that, despite the previously mentioned large inter-annual variations, the average precipitation and other ambient conditions are shared with relatively many other regions of the world, which means that the empirical basis for the used model coefficients is good.
The ability of the model, calibrated to current conditions according to the above description, to reproduce available historical lake level variations was tested through simulation of lake level dynamics based on observed annual precipitation for the period 1978–1984. The inter-annual lake level variation was well reproduced with an average deviation from observed lake level of 8%. This is adequate, considering that variations in other variables (e.g., temperature) were not taken into account during simulation.
Moreover, since available historical data on average lake levels (covering 10 years; 1978 to 1984 and 2008 to 2011) did not overlap sufficiently with available data on average annual precipitation (covering the years 1973 to 2009), we investigated if the model, given a 50-year synthetic p data series with the same mean and standard deviation as the observed one (789 ± 278 mm/year), was able to yield lake levels that were consistent with the observed levels in terms of mean value and standard deviation. To ensure the synthetic time series is consistent with the observed series, we first performed normality and autocorrelation tests on the historical P dataset. Following the Weibull method [55], the observed p dataset was normally distributed with both its probability density function (PDF) and cumulative density function (CDF) within a 95% confidence range. Moreover, there was no significant autocorrelation within the dataset. Therefore, we assumed a Gaussian distribution, with zero autocorrelation to generate the synthetic time series.
Since estimates of the true standard deviation from only ten samples (historical lake level observations) are associated with uncertainty, we calculated a 95% confidence interval for this true standard deviation according to:where n is the sample size, is the sample standard deviation, and and are the right side and left side chi-square standard values for degrees of freedom. The performance of the model with respect to reproducing historical data was evaluated from the agreement between the mean lake level of the historical observations and the simulated one, as well as the consistency between the simulated lake level variation and the true value (checking if the simulated level variations fall within the confidence interval for the true level variations). We note that this test is based on an implicit assumption that precipitation variability is a main driver of lake level variation—this hypothesis was tested separately through sensitivity analysis.
A sensitivity analysis was performed in order to determine the influence of four important hydroclimatic parameters (precipitation, temperature, cloud cover and relative humidity) to the lake level and the lake evaporation. This sensitivity analysis involved varying one parameter at a time over a certain range of values and observing the resulting change in lake level and lake evaporation. Precipitation and air temperature were varied at regular intervals over a range of values to drive the lake level from dry-out to overflow conditions. Cloud cover and relative humidity were varied over their full range of possible values (0%–100%).
2.4. Assessment of Future Climatic Conditions
In order to assess the lake response to future climatic changes, ensemble means of projected future temperature and precipitation changes from four Representative Concentration Pathways (RCPs) of the Coupled Model Intercomparison Project, Phase 5 (CMIP5) [56] were used to force the calibrated model from current conditions. The data were retrieved from the Royal Netherlands Meteorological Institute (KNMI) Climate Change Atlas [57]. Accordingly, over the 21st century, the study area is expected to experience a temperature rise of between 0.75 to 3.5 °C and an increase in average annual precipitation of around 5% to 10% (Table 2). When using these future projections, simulations were run for the mean future changes as well as for the means plus/minus one standard deviation, to have an idea on possible variability. During simulation, the total projected changes were linearly distributed over a 100-year period, while keeping model parameters fixed at their present day calibrated values.
3. Results and Discussion
3.1. Reproducing Current Conditions and Historical Observations at Lake Babati
The estimated lake and its catchment water balance components are presented in Table 3. The simulated average water level is 5.32 m, that is 50 mm (1%) higher than the observed average level (5.27 m) between 2008 and 2012. Surface evaporation from the lake amounts to 1.44 × 107 m3 (2075.7 mm/year), i.e., more than twice the precipitation volume of 5.331 × 106 (789 mm/year), thus represents an important part of the water budget over the lake.
This is typical of many East African and tropical lakes, such as Lake Manyara [6], Lake Nakuru [58], Lake Ziway [4], and many others [59,60]. The total precipitation volume over the whole catchment (including the lake) is 2.72 × 108 m3/year which is however far greater (almost 20 times) than the lake surface evaporation volume (1.44 × 107 m3/year).
The current groundwater flux from the lake is estimated to be 3.67 × 106 m3/year representing about 26% of the average lake volume. The actual evapotranspiration loss over the catchment (excluding the lake) is 2.55 × 108 m3/year, which is approximately 93% of the total catchment precipitation. This is consistent with an earlier suggestion by [21], who reported a catchment runoff coefficient between 2% and 10% for the study area. The net lake evaporation depth (the difference between evaporation and precipitation depth over the lake) is 1286 mm/year while the lake inflow factor (i.e., the ratio of surface and groundwater inflow volume into the lake to the total input volume to the lake by surface inflow, groundwater flow, and direct precipitation) is 0.7. The latter is comparable to those of other East African terminal lakes, including Lake Manyara (0.5) [6], Lake Naivasha (0.7), Lake Awassa (0.5) and Lake Shala (0.7) [61].
Considering historical conditions, the simulated average lake level was 5.05 m, with a standard deviation of 0.9 m (Figure 7). This value corresponds to 4% less than the observed lake level (5.27 m). Furthermore, we calculated the 95% confidence interval for the true standard deviation of the historical lake level to range from 0.41 to 1.09 m (i.e., an observed standard deviation around 0.7 m). Hence, the simulated standard deviation of 0.9 m falls within this confidence range. Although this suggests about a 30% bias in temporal variability of lake level, we consider that the model can reproduce fairly well the variations of the past in terms of lake volume.
3.2. Sensitivity Analysis
The lake level sensitivity to changes in precipitation, temperature, cloud cover and relative humidity are presented in Figure 8. The horizontal dashed lines represent the current lake level and the vertical dashed lines correspond to the current value (present conditions) of the respective parameter. It is observed that precipitation change has a relatively large impact on lake level (Figure 8a). For example, an increase of about 10% (90 mm/year) in annual average precipitation would lead to lake overflow (1.5 m rise), while a 17% (140 mm/year) decrease in rainfall results in dry-out conditions (5.3 m drop). In contrast to this, temperature changes inversely affect lake levels (Figure 8b) with a 2.4 °C temperature decrease from present conditions resulting in lake overflow while a 3.6 °C increase leads to lake dry out.
Lake levels are also relatively sensitive to changes in cloud cover fraction (Figure 8c). A 30% increase in cloud cover fraction from present conditions results in lake overflow, however, complete dry-out could not be obtained even if the cloud cover fraction were to be reduced to its lowest value (0%). Apparently, there is no appreciable response in lake level when the cloud cover drops below 20%. Another important observation is the significant impact of cloud cover fraction on lake evaporation. Changing the cloud cover from 0% to 70% would cause lake evaporation to drop substantially by about 2000 mm/year, i.e., about 285 mm/year for every 10% change in cloud cover. Changing relative humidity (Figure 8d) seems to have little effect on lake levels; varying relative humidity from 0% to 100% results in only a 1 m water rise. The effect of relative humidity on lake evaporation is also less pronounced and mainly occurs above 50%. Over the full range of relative humidity (0%–100%), the change in lake evaporation is about 400 mm/year. This corresponds to an average reduction of 40 mm/year in lake evaporation for every 10% decrease in relative humidity. The magnitude of change in each of the four parameters required for bringing the lake level from dry-out to overflow conditions are summarised in Table 4.
The sensitivity analysis results indicate that the lake is highly sensitive to changes in precipitation, and relatively sensitive to air temperature and cloud cover fraction, while less sensitive to changes in relative humidity (Figure 8). Our results support those of [60], who studied the sensitivity of 10 East African lakes to climate fluctuations. They associated high lake level sensitivity not only to the size and morphology of the lakes, but also to higher values of the aridity index, a factor which directly reflects precipitation and evaporation contribution [62]. Likewise, high sensitivity to changes in precipitation has been observed at Lake Suguta, Kenya [8]. The exceptional low sensitivity to precipitation at Lake Tana has been associated with its relatively significant outflow [5].
High sensitivity to temperature has been reported for Lake Ziway, Ethiopia [4], and Lake Victoria [3,11] whereas the impact of cloud cover on the level of East African lakes seems not to have been reported before; its relatively high impact on lake evaporation has also been seen for Lake Victoria, where lake evaporation was reduced by 252 mm per year (15%) when cloud cover increased by 7%. Similar findings are reported for the Nakuru-Elmenteita lake basin, Kenya, where a 10% increase in cloudiness resulted in a 5.5% reduction of lake evaporation [58]. A methodologically similar study to ours was conducted by [63], who investigated the impact of sunshine index (a proxy of cloudiness) on the level of Lake Bosumtwi, Ghana (West Africa), showing as in the present case, a large impact. Finally, the relative humidity was found to have nearly no effect at Lake Ziway [4].
Considering that available precipitation and temperature data are often less uncertain than cloudiness data due to more frequent and direct measurement, our results emphasise the importance of considering the cloudiness as a crucial factor in estimating lake surface evaporation. This aspect has often been overlooked in most lake-catchment modelling studies in the region. However, it is important to note that the lake sensitivity results presented above are influenced by the calculation methods and assumptions made. For example, lake evaporation was calculated by the energy balance method, whose sensitivity to air temperature is relatively higher than in the Penman method [3]. Similarly, evaporation is slightly more sensitive to relative humidity changes in the Penman method than it is in the energy balance equation or the Complementary Relationship Lake Evaporation (CRLE) model [4]. Besides, as also observed by [60], lake size and morphology plays an important role in lake sensitivity to climatic forcing.
3.3. Lake Babati Response to Climate Change and Variability
The solid lines of Figure 9 show the lake response to the ensemble mean projection of changes in temperature and precipitation over the 21st century, for different climate forcing scenarios (green—RCP2.6: cyan—RCP4.5; blue—RCP6.0; red—RCP8.5). Two distinct lake evolution patterns can be observed, depending on the relative importance of the opposite effects of temperature and precipitation. The first pattern brought about by the RCP6.0 scenario (+2.5 °C, +10%P) and RCP8.5 (+3.5 °C, +10%P) indicates that the current lake level will drop by 1.6 m and 3.4 m, respectively, at the end of the century. Volumetrically, this corresponds to 61% and 93% reductions at the end of the century. Such depletion would directly impact the water supply availability for Babati town and would have serious implications on the sustainability of the lake aquatic ecosystem (e.g., hippos, fish and birds).
The second pattern brought about from the RCP2.6 scenario (+0.75 °C, +5%P) consists of a gradual water level rise, leading to lake overflow level after about 80 years. This would be positive in terms of water availability and aquatic ecosystem support, however, it would reduce considerably the lake's flood buffering capability and, thus, increase Babati town vulnerability to flooding. The RCP4.5 scenario (+1.5 °C, +5%P) does not seem to affect the lake level significantly.
Although the above discussed ensemble mean projections generally have better predictive capacity in hydrological and lake balance applications than individual model results ([12,53]), an important observation is that output from individual climate models in the present case yield large differences in predicted lake response. More specifically, the shaded area bordered by dashed lines in Figure 9 indicates simulation results for the ensemble mean temperature and precipitation plus/minus one standard deviation. The funnel-like shape of all shaded areas in Figure 9 suggests that for any of the four climate forcing scenarios, Lake Babati could reach overflow conditions in as soon as twenty years. On the other hand, with the exception of the RCP4.5 scenario, the lake could potentially dry out [about 45 years (RCP8.5), 60 years (RCP6.0), and 90 years (RCP2.6)]. This high variability in lake response can be explained by the high variability in precipitation predictions within individual climate model projections. The standard deviation of the projected precipitation increase ranged between 26% and 33% (Table 2). According to sensitivity results (Section 3.2), this is comparable to the amount of precipitation change that could drive the lake from dry-out to overflow conditions. On the other hand, the maximum standard deviation in projected temperature change across the four scenarios is 0.6 °C, which is only 10% of the total warming or cooling required to move the system from overflow to dry-out.
Our results emphasize that the high uncertainty in the ability of individual global climate models (GCMs) to project future rainfall changes in the tropics may result in high uncertainty in both magnitude and direction of the simulated hydrological responses of highly sensitive systems. This amplifies the vulnerability in Lake Babati owing to the lake's high sensitivity to slight changes in precipitation and makes it difficult to project robust future lake level estimates independent of the future emission scenario considered. While it is this sensitivity that has likely brought about the limited attempts to quantify actual impacts of future climate change, as projected by GCMs, on lakes response in East Africa, there is still a need to consider lake evolution through various scenarios as such investigations can potentially inform management options. For instance, ensemble mean projection results that are known to have better predictive than individual models results suggest in the present case that a future temperature increase by 2 °C or more increases the risk of complete lake dry-out. Managing the profound effect on regional water resources of such a development is associated with considerable challenges that most likely would need to be identified well in time in order to reach viable and efficient solutions. Future work coupling groundwater and lake interactions that allows characterization of, for example, spatiotemporal variability of landscape responses (e.g., [64]) thereby isolating sub-annual fluxes and process shifts could help isolate impacts of the largest GCM uncertainties. Further, utilization of downscaled modelling output or regional models may help refine the large uncertainties in future projections. Lastly, it should be noted that the validity of analysis above might be influenced by a number of other factors in addition to the GCM uncertainty which were not explicitly considered in the model. For example, future shifts in cloud cover fraction will affect lake evaporation and alter the lake response. Also, land cover changes could alter surface runoff (e.g., [65]), sedimentation, groundwater discharge, lake storage and buffering, eventually attenuating or aggravating the climate change impacts.
4. Conclusions
Based on region and site specific hydrogeological and hydro-climatic input, a novel coupled approach that accounts for lake water-groundwater interactions could reproduce existing observations on current and historic lake levels of the semi-closed freshwater Lake Babati in Tanzania (East Africa). Results on lake level sensitivity to cloudiness (cloud cover), which seems not to have been assessed for East African lake systems before, show that cloudiness is a main parameter affecting lake levels together with precipitation and temperature. Increased focus on cloud cover measurement and interpretation could likely improve projections of lake levels and surface water availability, since cloudiness generally is subject to less frequent and direct measurements than precipitation and temperature. Precipitation change had a relatively large impact on lake levels as seen previously in other studies. We conclude more specifically that the divergent results on the future (21st century) development of Lake Babati can be explained by the fact that the variability in precipitation output of individual CMIP5 global climate models is comparable to the amount of precipitation change that is needed to drive the model from lake dry-out to overflow; this condition is likely shared with many other East African lake systems. Relatively dependable ensemble mean projection results show that a future temperature increase by 2 °C or more increases the risk of complete lake dry-out. Managing the profound effect on regional water resources of such a development is associated with considerable challenges that most likely would need to be identified well in time in order to reach viable and efficient solutions. More generally, present results highlight key change-driving processes and factors in the complex dynamics relating lake systems response to future climatic changes, indicating that it could be useful to apply the methodology to study other water bodies in data-scarce areas of tropical Africa, in order to support sustainable water resource planning and management.
The authors acknowledge financial support from the Swedish International Development Agency (Sida) Project Number SWE-2011-066 and Sida Decision 2015-000032 Contribution 51170071 Sub-project 2239.
Author Contributions
René P. Mbanguka and Jerker Jarsjö conceived and designed the study, René P. Mbanguka performed simulations, analysed the data and wrote majority of the manuscript, Jerker Jarsjö and Steve W. Lyon contributed analysis and write-up, Marc Girons Lopez provided initial modelling codes, and Karin Holmgren contributed to write up.
Conflicts of Interest
The authors declare no conflict of interest.
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Figure 6. Model Response Map for calibration of cloud cover C and factor Xc (contour levels represent deviation between simulated and observed lake water level).
Figure 7. Simulation of Lake Babati level variation based on a 50-year random precipitation time series generated using historical mean and standard deviation values of precipitation for the period 1973 to 2009.
Figure 8. Lake water level sensitivity to changes in (a) Precipitation; (b) Temperature; (c) Cloud Fraction and (d) Relative Humidity. The horizontal dashed line represents the current lake level and the vertical dashed line corresponds to the current value of the respective parameter.
Figure 9. Lake Babati response to climate change scenarios. The thick solid lines represent lake response to ensemble mean change in precipitation and temperature; the shaded areas represent the one standard deviation confidence range for each scenario; bounded with thin dashed lines of the same color as the mean response lines.
Table 1. Summary of model input variables, physically plausible range of parameters used in the calibration, and resulting optimum parameter value after calibration to observations.
|Model Input
|Estimated Current Value
|Precipitation (mm/year)
|Temperature (°C)
|Relative Humidity (%)
|Lake surface area (km2)
|GW reservoir area (km2)
|Total catchment area (km2)
|Groundwater conductivity (m/day)
|Porosity (%)
|Calibrated parameters
|Physical range
|Optimum value
|Cloud Cover (C) (%)
|Calibration factor for ET (Xc)
Table 2. Projected future climate change at Lake Babati based on CMIP5 ensemble mean (2080–2100). The values in brackets represent the standard deviation.
|Climate Variable
|Temperature Change (°C)
|+0.75 (0.6)
|+2 (0.1)
|+2.5 (0.4)
|+3.5 (0.5)
|Precipitation Change (%)
|+5 (21)
|+10 (16)
|+10 (27)
|+10 (33)
|Lake depth (m)
|Lake volume (m3)
|1.391 × 107
|Precipitation over the lake (m3/year)
|5.331 × 106
|Precipitation over ground (m3/year)
|2.679 × 108
|Lake Evaporation (m3/year)
|1.437 × 107
|Actual ET over ground (m3/year)
|2.552 × 108
|Groundwater Leakage (m3/year)
|3.671 × 106
|Lake overflow volume (m3/year)
|Discrepancy (as % of Lake Volume)
|Net lake evaporation depth (mm/year)
|Lake inflow factor (-)
|Lake Level Change
|Temperature (°C)
|Precipitation (mm/Year)
|Cloud Cover (%)
|Relative Humidity (%)
|Current to Overflow
|did not occur
|Current to Dry-out
|did not occur
|did not occur
|Dry-out to overflow (absolute)
Note: n/a stands for "not applicable".
© 2016 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC-BY) license (http://creativecommons.org/licenses/by/4.0/).


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can someone give me tips on composing classically in the likes of Mozart, Dvorak, Beethoven etc.
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can someone give me tips on composing classically in the likes of Mozart, Dvorak, Beethoven etc.
This is Vash Hartman's alternate account because google hates me.
and if you think other wise go jump in a river
This is my third Nocturne in Db Major, composed for "Mrs.Topping." I like how this one turned out to be honest, much better than the previous one at least.
Nocturne No.3 in Db Major (KJC 7): https://musescore.com/kjc/scores/5884144
Hi! I seem to recall there used to be a way to specify/choose various muted brass timbres, but I'm having trouble relocating that info: am I misremembering? (My present need is for an F-horn "con sordino," but I'd appreciate the general knowledge of either how to or where to find such timbre mods.) Thanks!
I arranged another piece from Morse. Check it out, let me know what you think. Chances are, if you comment on mine, I'll take a look at yours. https://musescore.com/user/31989152/scores/5882300
Revised and extended!
Being totally honest, I kind of ran out of ideas for this nocturne. However, I might as well upload it anyway since it is listenable at least.
Nocturne No.2 in B Major: https://musescore.com/user/31902485/scores/5882219
Made my first Nocturne (E Major) today. If you want to listen, here is the link:
I have a challenge!!! Who can write / re-write Bonobo : Black Sands into sheet music?
Hi there composers,
This is a song without words for Trumpet, and my first attempt with that instrument. I'd be thrilled for your feedback. Thanks! - J
I finished my second prelude. I have to admit that I didn't expect to finish it so quickly and I think the result is very good.
Here are my compositions so far (the ones that fit this group). Comments would be appreciated.
Sequence Study in C Minor: https://musescore.com/user/31902485/scores/5880373
A front ensemble lot tune! It has sound effects and panned audio! MANY time signatures (9 to be exact) and it sounds spectacular! You wouldn't wanna click away! Enjoy!
Be sure to like, critique, and follow! Also, check out our penultimate project, Never Forget!
I've been playing it for 1 1/2 years
Hello Fellow Brass Musicians,
I have been playing trumpet for a while now. My range goes all the way to double C and a Double B flat(Meaning a good tone on B Flat). As my range goes up, I noticed that my resistance is not as good (I loose my chops faster, and can only practice my music for an hour before I have to stop) I have tried loosening up and using more air to hit high notes but it still doesn't work. If any of you could help, I would appreciate it so much!
Ok, so I finally finished Rain and I would really appreciate your opinion and some advices.
Thanks a lot ;D

subset: commoncrawl


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Using project teams to create MIS products
a life cycle analysis
Traditional management theory suggests that there should be parity of authority and responsibility in MIS project management.A survey was sent to 1610 randomly selected managers from the Directory of Top Computer Executives to answer the question, Do MIS project groups tend to have consistent responsibility across the stages of the product life cycle? The survey focused on five stages of the life cycle which are: project initiation, project approval, project design, project implementation, and project maintenance.462 replies showed the results that there is not parity of responsibility throughout the product life cycle. Rather, responsibility increases with each phase of the project.
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A villager walks through a parched paddy in Tianlin county, in the Guangxi Zhuang autonomous region, on Saturday.
A lingering drought has resulted in below-average water levels in 549 small and mid-size rivers and has left 673 small reservoirs dry in south China's Yunnan province, provincial drought relief authorities said Tuesday.
Affected by the drought, the total water inflow volume into all river courses in Yunnan is about 31 percent below the annual average, according to the Yunnan provincial flood control and drought relief headquarters.
To date, the Yunnan provincial government has earmarked 2.552 billion yuan (about 404 million U.S. dollars) as drought relief funds.
To date, the drinking water shortage has been temporarily solved for over 5.56 million people and 2.7 million large heads of livestock, said the headquarters.
As of May 8, the severe drought had affected 8.97 million people and destroyed more than 12.63 million mu (about 842,000 hectares) of cropland.


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{A Dash Of Luxury was born in 2013. However, some posts are from before A Dash Of Luxury was created and made public. Therefore, dates may be older.}
Montjuic is located just off Plaza Espana. It's high on a hill with views overlooking the harbor and city. There's a castle, fortress, fountain, the National Palace, and so much more! Visitors can actually take a cable car up, however, we arrived on the opposite side and walked it.
We were so tired by the time we got here (we did this on the same day as Parc Guell), so we didn't make it very far. We saw the Magic Fountain and National Palace (which now houses the National Art Museum of Catalonia).
I'm a little sad we didn't visit at night, as the Magic Fountain lights up to music. It looks so pretty in pictures. Truthfully, I wish we got to explore more of this area, because there's so much to see and do. Nevertheless, my feet couldn't take anymore, so we headed back to the hotel earlier than I had expected. No regrets. Anyway, learn from me and do NOT do this the same day you visit Parc Guell. It's too much in one day!
Here are some pictures of what we did see of Montjuic!


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Like all children of military families, Susan spent her childhood moving from one duty station to the next. An ardent student of human nature, she acquired a love for ancient history and myth, a fascination for the ridiculous and unusual, and is the first to admit, she still collects way too much useless information. These days, when not working as a Registered Nurse, she writes whenever she can. When not writing, her favorite things to do are spend time with family, read, watch movies, garden, take black-and-white photos, travel, and remodel her house.
Romance versus Science. Which one will win?
The love of Lacey Daniels life is her comic strip, Love Lessons 101, with principle players, Georgette and Frank, more like real people than made-up characters. Georgette wants a man. And not just any man. A real man who can weather life's storm. Lacey just wants to make the old-fashioned idea of courtship look sexy and fun for her readers, and she wants national syndication. Two things stand in her way. A contrived contest pitting her romance against the science of a new book, The Power Of Pheromones. And the book's author, hunky, catch-your-breath Zane Tyler.
Zane Tyler's mission is to give his sister and niece a stable, comfortable life. When he literally bumps into a beautiful stranger on the way to giving a lecture on how women choose their mates by smell, he's surprised to learn she makes a living by promoting old-fashioned romance as the primary ingredient to finding that one special person. Before he can get out of the line of fire, he's caught up in a battle of words that quickly escalates into a hokey competition where he has to come out the winner or lose everything he's worked so hard to build.
Go on a couple of dates with Doc Michaels and you'll find true love with someone else.
Dr. Gavin Michaels has somehow turned into the town matchmaker. Now it's his turn. The first step in his grand scheme is to sell his practice and take a teaching position at the Health Sciences University in nearby Portland. But Rosewood has other plans for his heart—in the form of a vulnerable woman who needs more from him than to buy his practice.
On the run from the memory of an abusive marriage, newly widowed Dr. Vivan Buchanan is looking for a place to lick her wounds and start over. Not just for herself, but for her step-daughter and unborn child. Landing in Rosewood, Oregon on Valentine's Day, she finds lodging at Irene's Boarding House. But can the lover's holiday, a new practice, and a man unlike her late husband open her heart to the possibilities of trust and love one more time?
Heartwarming stories about family...community...and the journey home
When friends become lovers, is there a chance friendship can turn into something more?
Cyber security consultant, Sloane Cooper is dumped by her wanna-be politician boyfriend, his parting shot—not only are you the worst girlfriend I've ever had, but you're a lousy kisser, too! So she turns to game developer Miles Preston for "kissing lessons", but very quickly realizes, though there's a surprising attraction there, playing kissing games with her safe, easy-to-talk-to best friend isn't the solution to her problem.
Who is the real Sloane Cooper?
For two years Miles has been Sloane's best friend while he watched her play house with another guy. Secretly he's wanted more, but never once thought he'd catch her on the rebound. How does he convince the enchanting woman steamy kisses are not enough? Helping her open a cyber cafe is a start, but the real fun begins when he hires her to alpha test his new game. Traditional wooing won't work. Can a few well chosen gaming obstacles do the trick instead?
"Deck the halls with boughs of holly..."
It's time to put down roots, and all Victoria Cahil wants is to keep the promise she made to her eight-year-old niece, MacKenzie. They would spend Christmas Eve in their new Queen Anne colonial home. There was only one hitch in her plan. The house needs more work than she anticipated, and Chief Deputy Gavin Stevens has put the derelict house on his "dangerous buildings" list.
Okay with his bachelor status, Gavin hasn't given a second thought to finding a family of his own...or the love of a good woman. He's survived being orphaned at a young age, Marine boot camp, three tours in a war zone, and is not often taken by surprise. But when a fiesty house renovator calls him on the carpet for condemning the sow's ear she's determined to make into a silk purse, he begins to wonder. Can he survive the provocative Tori Cahil with his heart...and bachelorhood intact during a holiday season when Christmas miracles are practically the norm?
Heartwarming stories about family...community...and the journey home
Alice York lives a nomadic life working as a classic car mechanic so she can follow her dream of painting landscapes. Then she breaks down in Sellwood and takes a temporary job with sexy Zach Barret, but getting drawn into this single dad's delightful family is not on the menu.
Zach Barret has two priorities – be the best dad he can to his twelve-year-old daughter and keep Martha's Elder House running without hiccups, a challenge at the best of times since his granddad persists on chasing off the hired help.
When a gypsy caravan-style truck breaks down at Martha's curbside, the last thing Zach needs is an impulsive pixie rocking his boat. The more determined he is to stay away from the free-spirited, green-eyed nomad, the more he finds one kiss is not enough. Uncovering her secrets in paintings of empty swings and merry-go-rounds puts a new priority in the top spot on his short list. Can he convince this stunning woman to park her truck permanently in his drive?
Rediscover the magic and romance of Valentine's Day with these nine stories of Gifts From The Heart. Stories of best friends, lost chances, first love, love renewed, and new love will bring a tear to your eye and a little skip in the beat of your heart.
Read about a wounded warrior saved by a ring. Empathize with two different widows as they strive to overcome their past and open their hearts to trust again. Follow a survivor of the Titanic as she boards another ship and her past and future collide.
Shiver with the cautionary tale of the prison of love in the legend of Ann'er from the dark world of Thorn. Laugh at the humorous escapades of a young woman led to find love through the questionable assistance of her cat. Then finish this volume by relaxing in the fairy-tale world of a little dog who helps a sad and lonely princess learn to accept the unconditional love of pets.
"The Telltale Heart" by Sarah Raplee, "Is He the One?" by Judith Ashley, "Saved by the Ring" by Diana McCollum, "Be My Valentine" by Susan Lute, "Dancing on Water" by Mercer Addison, "Heart of a Highlander" by Collette Cameron, "The Flaming Heart of Winter" by Pamela Cowan, "Matchmaker Cat" by Jane Killick, "Metro Goes to London" by Susie Slanina
Five Friends. Five Yearbook Predictions. Twelve years. Was it Destiny? Or the last act of girls ready to take on the world?
As thirty approaches so does their Thirty-Years-Old-and-Made-It Reunion Party. Who will have conquered New York? Become a CEO? Be married with a bunch of kids? Which girl will have nailed the lucky Charley Vargas? Is Prince William safe? Because someone is supposed to marry a prince.
It's the midnight hour and the scramble is on. Not one of them wants to admit her life hasn't turned out the way she expected. Maybe reaching thirty and living up to friends' predictions is not all it's cracked up to be.
From the Dragonkind Chronicles – the battle is just beginning...
In a post apocalyptic world where Darwin changelings emerge from hiding and humans struggle to reclaim their former glory, mercenary Logan Pen doesn't want to save the world. His mission is to protect his greatest treasure - his family. That is until he tries to capture a shadow thief. Beyla, a beguiling, emotionless Umbra steals his telein - a talisman forged at his birth while escaping his grasp, making her by ancient dragon law his mate.
Her enemy - a fiery Naga - and the talisman she's stolen from him rouse emotions Beyla has spent three long years in the land of shadows stripping away. Still she hasn't been able to banish the grief and pain left by the murder of her human family.
Fighting a desire that flames out of their control, and scrambling to save humanity and their own kind, Logan and Beyla are forced to join forces to keep a weapon of incredible destructive power out of the hands of the man who would use it to conquer their world. With evil on the brink of victory, only through sacrifice do they learn to trust and embrace the love that will change them forever.
Same great novelette. New cover.
Celebrating Christmas is the last thing on former Marine David Randall's mind when he leaves behind his military life to take care of his newly orphaned nephew. But when the job waiting for him is suddenly eliminated, he takes the only position available – a temp position with the buttoned-down daughter of the CEO of Banks Sportswear. Appearances are not always what they seem. And a growing attraction for his new boss spells trouble with a capital T.
A frustrated overachiever, whether playing the spoiled rich girl, or trying to prove she has what it takes to make it in her father's corporate world, Charlee Banks has until the company Christmas party to come up with a proposal to expand the family business in the domestic market. Saddled with a temporary administrative assistant who is a mis-fit for the job if ever there was one, it's not long before a shattered heirloom ornament, a little boy's tears, and a hero's broken heart has workaholic, Charlee Banks realizing there's one Christmas proposal she'd better get right.
Dr. Dana Murphy has everything a physician can want. Everything except the one thing she can't get back. When she's diagnosed with a degenerative condition that threatens the career she loves, and her husband discovers he has a teenage daughter, it all begins to unravel. When her crazy mother and sister come to stay, in the chaos that follows, she scrambles to scotch tape her life back together and instead finds herself on the brink of losing everything she holds dear.
Stella Carmichael can't believe her life with her husband, though not always perfect, is over. All she wants is to shut herself away in their too empty house, and turn her back on the world she's quite certain will go on happily without her.
Thanks to her interfering daughters, she's exiled to London. Instead of licking her wounds in solitude, Stella's babysitting a rebellious teenager, and having to make sense of her life thousands of miles from home. Repairing her family's fragile relationships is not an easy task. While getting to know her sullen granddaughter, meeting new friends, and embarking on an unexpected flirtation, she discovers family is a gift; and living, something to be treasured.
All Benjamin Quincy wants is to make a stable home for his ten year old daughter in the town where he spent his childhood – the same town he later left in bitter disappointment. Young and hot headed, he made a mistake. Eleven years later, he's a divorced, single dad with a troubled kid, and a lot to make up for.
Sydney Marshall has finally wrangled the perfect job at the most coveted travel magazine in New York. Does she care that her ex-boyfriend has returned to the tiny town of Rosewood with a precious daughter who's not hers? Does it matter that every time he comes near, her heart flutters madly like in the old days? No! Her bags are packed; plane tickets are stashed in her backpack; the adventure of a lifetime is about to begin.
There's only one problem. Life and Rosewood insist on interfering with the best laid plans.
Ten years before Madrid, Jane Donovan is a kid growing up in an orphanage and flirting with the wrong side of the law. Looking for the family that has eluded her, she has a choice to make. Live her mother's doomed life, or get off the streets. Finding the courage to reach for her dreams isn't easy, but in the end, will she take the road that will give her everything she's always wanted?
There's no place like home, and to Gunnery Sergeant Jane Donovan, home is the US Marine Corps. But, she's made a mistake. A tragic mistake that cost an orphaned kid from the poorest part of Madrid his life. Because of a little insubordination and disorderly conduct on her part, she's about to lose the one thing she values most. The family and good life she's forged in the Corps. Now she has one option. Put her future in the hands of Dr. Chase Russell, or become a civilian. The choice is hers.
Chase Russell has royally screwed up. Busy chasing a lucrative book deal that would legitimize his theories about treating war veterans suffering from Post Traumatic Stress Disorder, and let's face it, give him a certain amount of fame too, he missed a client's cry for help and subsequent admission to the hospital for a failed drug overdose. That the client was his brother makes his arrogance more reprehensible. In the aftermath, he leaves his lucrative practice in Chicago to start over on a lovely, neglected Central Oregon ranch, looking for the peace and sanctuary he craves, but hardly deserves.
When the Marine arrives, nursing a cranky hip and an even crankier disposition, he wants nothing to do with her, but the fun is just beginning. Between helping two runaway kids, and taking the stubborn Marine through play therapy, what's an ex-counselor to do, but make sure this hero finds her way home.


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Dirk Nowitzki makes season debut after knee surgery, scores 8 points in Mavs' loss to Spurs (VIDEO)
Merry Christmas Eve, Dallas Mavericks fans. I got you a 7-foot German. I hope it fits:
After being sidelined for the Mavericks' first 27 games following mid-October arthroscopic surgery on his right knee, legendary power forward Dirk Nowitzki made his 2012-13 season debut for Dallas on Sunday, checking in at the 6:28 mark of the first quarter of the Mavs' contest against their longtime nemeses and in-state rivals, the San Antonio Spurs. Dirk took a few minutes to work himself into the flow of the game, grabbing a pair of defensive rebounds and testing out the knee as he loped up and down the court before beating the Spurs' defense in transition, slipping to the rim and finishing a Darren Collison dish with a dunk for his first points of the season.
Nowitzki had tested his right knee in Dallas' practices last week, but he wasn't expected to return to the floor until after Christmas. Instead, the 2007 NBA MVP and 2011 NBA Finals MVP decided to give it a go "less than an hour before tipoff," according to Raul Dominguez of The Associated Press:
"Before the game I felt decent, so I said I'm going to give it a go," Nowitzki said. "I felt actually good out there. I thought the wind was OK, but my legs were a little heavy there after a couple of trips up and down but I thought I fought through it OK."
Nowitzki's return didn't affect Sunday's outcome too significantly — not many things could have, really, with San Antonio unleashing a franchise-record 20 3-pointers to turn the Sunday affair into a 129-91 laugher — but he acquitted himself well enough, scoring eight points on 3 for 4 shooting and grabbing six rebounds in the loss. Most importantly for Mavs fans, of course, is the fact that after some worry-inducing stall-outs in his rehabilitation and Dirk's own impatience about the progress of his comeback, he made it through his maiden voyage safely and without incident.
Dirk didn't get quite as much burn as he would've liked on Sunday — he'd planned to play about 25 minutes, but only saw 20, as he explained to reporters, including the Dallas Morning News' Brad Townsend, after the game:
"At the end of the third [quarter] we were down 80, so I didn't really have to go back in," Nowitzki said.
Glad to see Dirk's sense of humor is in midseason form. Welcome back, big guy. With Dallas at 12-16 and sitting 2 1/2 games outside the Western Conference playoff bracket, we know Mavericks fans are glad to see you; until you start draining daggers against the rest of our favorite teams, so are the rest of us.


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What You'll Need
After you get your location, model, and camera setup you're ready to start trying to catch a great hair flip shot. I always start out by having my model face away from the camera because you want them to turn fast towards the camera so you can catch the motion of their hair as they turn. I always tell my models to pick the expression they want to have in the photo and try to keep that expression as they turn fast towards the camera. Have your model keep their shoulders locked and their arms and hands locked into a position that doesn't have them flailing all around. Try to find an arm pose before hand so your model doesn't have to try and figure one out on the spot because this will make getting the perfect photo a lot easier. In the photo below I have my model hold flowers with her forward facing arm locked in an upright position holding the flowers and her other arm at her side so it doesn't take away from the photo at all.
Once you have your model's facial expression and body position it's time to shoot. If you are just starting out then you'll want to use the Continous Shooting mode on your camera. Start shooting a second before you have your model turn and flip their hair so you have enough time to capture the photo. Then just have your model turn towards the camera flipping their hair! After you get the hang of it you'll be able to shoot the photo without haveing the continous shooting mode on. It's just a process of trial and error, just keep shooting till you finally figure out a method that gets's you that perfect hair flip shot!
Thank you for checking my site out! Find me on Instagram: @moreboom7
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October 2019


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First I would suggest you use the search on the bottom of your screen and search for the Bright AO. It is free and has really nice animations so you don't have to do the Linden duck walk. Next, you can keep the original avi you have or start tricking in out. A good way to do that is to join several Midnight Mania groups. That way you can get a variety of skins, avatars, clothes, buildings, etc and get to know some of the stores around. There are also a number of hunts going on where you go from store to store looking for a hidden object of some kind that will have a free gift from the store, which is another way of getting to know the grid and what is available out there. I have found some of my favorite stores from a grid hunt.Again, using your search, look under events and then search under education. There are a number of classes offered by NCI, among others, that give you a lot of information about SL and what to do. You can also look under Showcase for some of the places to go to in SL. From there, use your imagination and have fun.


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Premier Brad Wall is ripping into the federal government after Prime Minister Justin Trudeau's announcement of a federal tax on carbon emissions Monday.
"I cannot believe that while the country's environment ministers were meeting on a so-called collaborative climate change plan, the Prime Minister stood in the House of Commons and announced a carbon tax unilaterally," Wall said in a statement.
"This meeting is not worth the CO2 emissions it took for environment ministers to get there," the statement continued. "The level of disrespect shown by the Prime Minister and his government today is stunning. This is a betrayal of the statements made by the Prime Minister in Vancouver this March. And this new tax will damage our economy."
Wall called it "one of the largest national tax increases in Canadian history," saying Saskatchewan would investigate "all options" to mitigate the impact.
Environment ministers from Saskatchewan, Nova Scotia, and Newfoundland and Labrador walked out of the meeting Monday with federal counterpart Catherine McKenna before what was to have been a joint photo opportunity.
"We're struggling to understand where the PM's message came from today and what's going to happen moving forward," said Margaret Miller, explaining Nova Scotia feels let down and surprised.
In a statement, Miller said NovaScotia has already met Canada's target of a 30 per cent reduction in emissions from 2005 by 2030, and has hoped the province would be spared carbon pricing.
In stark contrast, the B.C. reaction was complacent to the point of smugness.
"B.C.'s carbon tax is the highest and most comprehensive carbon price in North America," said Environment Minister Mary Polak. "But we need other jurisdictions to catch up to our carbon price before we raise our carbon tax, to ensure B.C. remains a competitive place to invest."
The B.C. government has already said its carbon tax will start increasing only in four years when the rest of the country catches up to the current levy of $30 a tonne.
Trudeau announced on Monday the federal government would establish a "floor price" of $10 a tonne on carbon pollution in 2018. That price will rise to $50 a tonne by 2022.
Trudeau gave the provinces just two options for implementing the carbon price: Either impose their own direct price on carbon that meets or exceeds the national floor price, as British Columbia has already done, or set up a cap and trade system, such as Ontario and Quebec are developing.
If provinces don't play along, Trudeau said, a tax would be implemented by the federal government on them. Any revenue generated from the tax, Trudeau told the House of Commons, would stay in the province it came from.
"There is no hiding from climate change," he told the Commons on Monday. "It is real and it is everywhere."
"We cannot undo the last 10 years of inaction. What we can do is make a real and honest effort — today and every day — to protect the health of our environment and, with it, the health of all Canadians."
Trudeau's pre-emptive announcement landed like a grenade in the midst of the environment ministers' meeting in Montreal, where federal minister Catherine McKenna was supposed to be hashing out an agreement on carbon pricing with her provincial counterparts.
"The air was sucked out of the room," Yukon's Currie Dixon said of Trudeau's announcement.
Moe suggested the federal government forcing a tax could be on par with Pierre Trudeau's National Energy Program, which was introduced in 1980 and led to ongoing animosity between western provinces and the federal Liberals.
"Many westerners will see this as National Energy Program 2.0," he said.
Moe said the carbon tax will cost each family in the province about $1,250 a year and the province $2.5 billion, while at the same time threatening jobs in the energy sector.
Wall has long said the province cannot afford a carbon tax, especially since the energy sector is already seeing lower profits.
"As I have said many times before, we are having the wrong conversation in Canada," Wall said in his statement. "The national focus on carbon pricing holds the lowest potential for reducing emissions, while potentially doing the greatest harm to the Canadian economy. We produce less than two per cent of global GHG emissions. Whatever impact the federal carbon tax will have on Canada's emissions, global GHG emissions will continue to rise because of the developing world's reliance on coal-fired electricity. Canada can make an important contribution in the battle against climate change by developing made-in-Canada solutions in areas like power production, transportation, natural resource development, manufacturing and construction."
Wall had previously threatened legal action against the federal government imposing a tax on provincial crown corporations, such as SaskEnergy.
"We'll have to look at what our opportunities are," said Moe, when asked about the possibility of a legal challenge on Monday.
While Alberta's NDP government supports a common price on carbon across the country, Premier Rachel Notley served notice that she'll oppose the federal plan until she sees "serious concurrent progress" on the pipelines that her province needs to get its oil sands crude to tidewater.
"Albertans have contributed very generously for many years to national initiatives to help other regions address economic challenges," Notley said in a written statement.
"What we are asking for now is that our landlock be broken, in one direction or another, so that we can get back on our feet."
Quebec's David Heurtel, the chairman of the meeting, and Ontario's Glen Murray both welcomed the new federal policy, saying it fully recognizes their provincial jurisdiction.
With files from Vaughn Palmer of theVancouver Sun, and the Canadian Press


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"What is your state of residence?" will likely be one of the first questions asked. The plaintiff must be a resident of the state where the divorce proceedings are filed. The defendant's residency does not usually affect the state's jurisdiction over the divorce action, but it may affect issues such as child custody and visitation. States have varying requirements for someone to establish residency, with most requiring that the person live in the state for a specified period of time and acquire a permanent address.
"Why are you divorcing the defendant?" will be another important question as many state courts require grounds or reasons for a divorce. Unless the state is strictly a no-fault divorce state, one or more pre-established reasons must be stated for filing for divorce. Fault-based grounds in many states include physical abuse, abandonment, adultery and drug abuse. Most states also recognize less accusatory grounds such as irretrievable breakdown of the marriage or irreconcilable differences.
"How long have you been separated?" Some states require a statutory period of separation in which the parties may not live together prior to beginning divorce proceedings. If that period is broken by any period of cohabitation in which it can be established that the parties shared marital relations, then the time period for separation may restart. Waiting periods may range from 6 months to 1 year in many states, and may be conditioned upon whether there are children born of the marriage.
"Do the two of you have minor children?" Whether there are children under the age of adulthood is a very important question as issues such as custody, visitation, child support and relations with parties of the opposite sex may become hotly debated. These issues are often emotional and complex and can extend the length of the proceedings.