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Despite the essential role of ecosystem goods and services in sustaining all human activities, they are often ignored in engineering decision making, even in methods that are meant to encourage sustainability. For example, conventional Life Cycle Assessment focuses on the impact of emissions and consumption of some resources. While aggregation and interpretation methods are quite advanced for emissions, similar methods for resources have been lagging, and most ignore the role of nature. Such oversight may even result in perverse decisions that encourage reliance on deteriorating ecosystem services. This article presents a step toward including the direct and indirect role of ecosystems in LCA, and a hierarchical scheme to interpret their contribution. The resulting Ecologically Based LCA (Eco-LCA) includes a large number of provisioning, regulating, and supporting ecosystem services as inputs to a life cycle model at the process or economy scale. These resources are represented in diverse physical units and may be compared via their mass, fuel value, industrial cumulative exergy consumption, or ecological cumulative exergy consumption or by normalization with total consumption of each resource or their availability. Such results at a fine scale provide insight about relative resource use and the risk and vulnerability to the loss of specific resources. Aggregate indicators are also defined to obtain indices such as renewability, efficiency, and return on investment. An Eco-LCA model of the 1997 economy is developed and made available via the web (www.resilience.osu.edu/ecolca). An illustrative example comparing paper and plastic cups provides insight into the features of the proposed approach. The need for further work in bridging the gap between knowledge about ecosystem services and their direct and indirect role in supporting human activities is discussed as an important area for future work.

The forced Korteweg-de Vries equation is now established as the canonical equation to describe resonant, or critical, flow over topography. However, when the fluid is uniformly and weakly stratified, this equation degenerates in that the quadratic nonlinear term is absent. This anomalous, but important, case requires an alternative theory which is the purpose of this paper. We derive a new evolution equation to describe this case which, while having some similarities to the forced Korteweg-de Vries equation, contains two important differences. First, a topography of amplitude α now produces a finite-amplitude response, whereas in the canonical forced Korteweg-de Vries equation, the response scales with α½. Secondly, the maximum amplitude the fluid flow response can achieve is limited by wave breaking, whose onset is characterized by an incipient flow reversal. Various numerical solutions of the new evolution equation are presented spanning a parameter space defined by a resonance detuning parameter, the topographic amplitude and a parameter measuring the strength of the stratification.

Long-term simulations using version 5.1 of the National Center for Atmospheric Research' Community Atmosphere Model at low (T42), medium (T106), and high (T266) resolutions were carried out to study the impact of horizontal resolution on the model's performance in reproducing the climatological features of precipitation over East Asia. The simulated spatial pattern of annual mean precipitation amount improves significantly with increased resolution. The low-resolution model is inadequate to reproduce the precipitation closely associated with fine-scale orographic forcing, such as the narrow large-rainfall belt along the southern edge of the Tibetan Plateau. The distribution of rainfall over and around the elevation of the Tibetan Plateau and high-altitude mountains becomes more realistic at higher resolutions. The proportion of the large-bias (small-bias) area continuously reduces (increases) when moving from T42 to T266 resolution. Simulations at all three resolutions can capture the key features of the major seasonal variation of rainfall arising from the onset and advancement of the Asian monsoon. A novel method is used to evaluate the sensitivity of the simulated intensity-frequency structure to the horizontal resolution. The proportion of light rain, which demonstrates large positive bias in climate models, decreases dramatically at higher resolution. The intensity-frequency structures averaged over steep-terrain regions and plain areas become more distinctive and realistic as the resolution increases.

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Numerical experiments are conducted to investigate the differences between summer precipitation over continental East Asia simulated by the Community Atmosphere Model, version 5 (CAM5), and superparameterized CAM5 (SPCAM5, a multiscale modeling framework). The results show that SPCAM5 effectively alleviates several original biases. Overestimates of precipitation on the eastern periphery of the Tibetan Plateau are reduced from CAM5 to SPCAM5 as a result of decreases in both the average hourly precipitation frequency and mean hourly intensity. Underestimates along the coastal regions in southern China are improved following a corresponding increase in mean hourly intensity and a decrease in average hourly precipitation frequency. The frequency–intesnsity relationship is also more realistic in SPCAM5. For western China, overestimated frequency values (in CAM5) of both weak-to-moderate (0–20 mm day−1) and heavy (20–50 mm day−1) intensity ranges are reduced in SPCAM5. For southern China, overestimates of frequency values (in CAM5) in the weak-to-moderate range are also reduced, whereas underestimates in the intense ranges are enhanced. In terms of diurnal variability, SPCAM5 generally exhibits a delay in the afternoon peak time and greater diurnal amplitude. The possible physical reasons for the variations in the precipitation between the models are further investigated. It is found that the change in deep convection intensity is a primary factor governing the shift in the precipitation simulations. SPCAM5 better simulates an intermediate transition stage from shallow to deep convection, which helps the deep convection to grow more fully to a greater magnitude, thus delaying the peak time and increasing the precipitation maxima.

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