We investigate acceleration in global temperature, defining acceleration as a supralinear (greater-than-linear) increase over time. We develop a statistical framework to test for supralinear trends using a linearithmic specification. Our results indicate evidence of acceleration in global temperature since at least 1990, with significance strengthening as more recent data are included. In contrast, evidence for acceleration under a quadratic specification is significant only in the longest estimation window. We also show that, if the true temperature trend is supralinear, standard break-point tests will eventually detect changes in the slope of a linear trend model, which may explain reported structural breaks in global temperature trends.

翻译：我们研究了全球温度的加速现象，将加速定义为随时间呈现的超线性（大于线性）增长。我们构建了一个统计框架，采用双对数线性模型检验超线性趋势。结果表明，至少自1990年以来，全球温度存在加速证据，且随着纳入更近期数据，显著性不断增强。相比之下，在二次型设定下，加速证据仅在最长估计窗口中显著。我们还证明，若真实温度趋势为超线性，标准断点检验将最终检测到线性趋势模型中的斜率变化——这或许可以解释文献中报告的全球温度趋势结构突变现象。