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Dáithí Stone Maximilian Auffhammer Mark Carey Gerrit Hansen Christian Huggel Wolfgang Cramer David Lobell Ulf Molau Andrew Solow Lourdes Tibig Gary Yohe 《Climatic change》2013,118(2):381-395
Future scenarios of the energy system under greenhouse gas emission constraints depict dramatic growth in a range of energy technologies. Technological growth dynamics observed historically provide a useful comparator for these future trajectories. We find that historical time series data reveal a consistent relationship between how much a technology’s cumulative installed capacity grows, and how long this growth takes. This relationship between extent (how much) and duration (for how long) is consistent across both energy supply and end-use technologies, and both established and emerging technologies. We then develop and test an approach for using this historical relationship to assess technological trajectories in future scenarios. Our approach for “learning from the past” contributes to the assessment and verification of integrated assessment and energy-economic models used to generate quantitative scenarios. Using data on power generation technologies from two such models, we also find a consistent extent - duration relationship across both technologies and scenarios. This relationship describes future low carbon technological growth in the power sector which appears to be conservative relative to what has been evidenced historically. Specifically, future extents of capacity growth are comparatively low given the lengthy time duration of that growth. We treat this finding with caution due to the low number of data points. Yet it remains counter-intuitive given the extremely rapid growth rates of certain low carbon technologies under stringent emission constraints. We explore possible reasons for the apparent scenario conservatism, and find parametric or structural conservatism in the underlying models to be one possible explanation. 相似文献
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The Cascadia subduction zone fault lies just off the Pacific coast of the USA and Canada. Although this fault has been seismically inactive over the written history of the Cascadia region, it has the potential to produce catastrophic earthquakes and tsunamis. A variety of dating methods have been used to show that the most recent Cascadia earthquake occurred in 1700. Among these methods is an informal analysis of oral traditions handed down by Native American peoples that appear to refer to a major earthquake in this region. A central difficulty in analyzing these narratives quantitatively is their use of a generation and other qualitative measures of time that have no fixed lengths. Here, these narratives are analyzed under an explicit statistical model of the lengths of these measures. The results raise a question about the previous conclusion that these narratives all refer to the most recent Cascadia earthquake.
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Estimating monthly streamflow values by cokriging 总被引：1，自引：0，他引：1
Cokriging is applied to estimation of missing monthly streamflow values in three records from gaging stations in west central Virginia. Missing values are estimated from optimal consideration of the pattern of auto- and cross-correlation among standardized residual log-flow records. Investigation of the sensitivity of estimation to data configuration showed that when observations are available within two months of a missing value, estimation is improved by accounting for correlation. Concurrent and lag-one observations tend to screen the influence of other available observations. Three models of covariance structure in residual log-flow records are compared using cross-validation. Models differ in how much monthly variation they allow in covariance. Precision of estimation, reflected in mean squared error (MSE), proved to be insensitive to this choice. Cross-validation is suggested as a tool for choosing an inverse transformation when an initial nonlinear transformation is applied to flow values. 相似文献
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Andrew R. Solow 《Mathematical Geology》2001,33(1):95-102
This paper describes a simple empirical Bayes approach to inference about the eruption rate of a volcano under a Poisson process model. Under this approach, the prior distribution of the eruption rate is estimated from the eruption records of a group of similar volcanoes. The approach is illustrated using the eruption records of six Central American volcanoes. 相似文献
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Andrew R. Solow 《Climatic change》2001,49(3):359-366
In conjunction with early climate records, catch records from pre-industrialfisheries are a potentially valuable sourceof information about the effect of climate on fisheries. This paper describesa test for a temperature effect on an18th century catch record of Icelandic cod. The results of the test, which isbased on a model that incorporatesboth internal population dynamics and a potential temperature effect, supportthe existence of a temperature effect. 相似文献
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Andrew R. Solow 《Mathematical Geology》1993,25(1):53-57
A common problem in geostatistics is to determine whether or not the value of a random field at an unsampled location exceeds a specified threshold using observed values of the random field at sampled locations. Under the indicator approach, the only information used to classify the unobserved value is whether or not the observed values exceed the threshold. This note shows that the loss of information from applying the indicator approach may be modest in the case where the underlying random field is Gaussian. 相似文献