We use simple pattern scaling and time-shift to emulate changes in a set of climate extreme indices under future scenarios, and we evaluate the emulators’ accuracy. We propose an error metric that separates systematic emulation errors from discrepancies between emulated and target values due to internal variability, taking advantage of the availability of climate model simulations in the form of initial condition ensembles. We compute the error metric at grid-point scale, and we show geographically resolved results, or aggregate them as global averages. We use a range of scenarios spanning global temperature increases by the end of the century of 1.5 C and 2.0 C compared to a pre-industrial baseline, and two higher trajectories, RCP4.5 and RCP8.5. With this suite of scenarios we can test the effects on the error of the size of the temperature gap between emulation origin and target scenarios. We find that in the emulation of most indices the dominant source of discrepancy...

中文翻译：

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模拟气候极端指数

我们使用简单的模式缩放和时移来模拟未来情况下一组气候极端指数的变化，并评估模拟器的准确性。我们提出了一种误差度量，该误差度量利用内部条件集合形式的气候模型模拟的可用性，将由于内部可变性而导致的系统模拟误差与模拟值与目标值之间的差异分开。我们以网格点规模计算误差度量，并显示地理解析结果，或将其汇总为全局平均值。与工业化前的基线相比，我们使用了一系列情景，这些情景涵盖了到本世纪末全球温度升高1.5 C和2.0 C，以及两条更高的轨迹RCP4.5和RCP8.5。通过这套方案，我们可以测试对仿真源方案和目标方案之间的温差大小误差的影响。我们发现，在大多数指数的模拟中，差异的主要来源...