The Southern Annular Mode (SAM) influences climate in the Southern Hemisphere. We investigate the effects of calculation method and data used to calculate the SAM index and how it influences the relationship between the SAM and climate. We propose a method to calculate a natural SAM index that facilitates consistency between studies, including when using different data resolutions, avoiding distortion of SAM impacts and allowing for more reliable results of past and future SAM trends.

One of the most common ways of reconstructing temperatures in the geologic past is by analyzing oxygen isotope ratios in fossil shells. However, converting these data to temperatures can be a technically complicated task. Here, we present a new online tool that automates this task.

Global mean surface temperatures are rising to levels unprecedented in over 100 000 years. This conclusion takes into account both recent global warming and likely future warming, which thereby enables a direct comparison with paleotemperature reconstructions on multi-century timescales.