Evolution of low-latitude climates and monsoon onset
Reconstructing past climate provides a powerful means to investigate how human-induced warming may be manifested in global climate. Over the last 65 million years, Earth experienced periods of extreme warmth with elevated greenhouse gas concentrations similar to projections of future climate. Of particular importance is understanding how low-latitude climate may respond to this warming due to its significance on both a local and global scale. At the local scale, low-latitude climate exerts a significant influence on the socio-economies of Earth’s most densely populated regions. Whilst at the global scale, low-latitude derived heat and moisture gets distributed poleward via a dynamic interplay of oceanic-atmospheric interactions. Thus, it is critical to fully understand a) how the low-latitudes will respond to this warming and b) the respective feedbacks on global climate. Yet characterisation of low-latitude climate during periods of warmer-than-modern climates is poorly constrained due to lack of data and limitations with the proxy methods applied to reconstruct climate variables (e.g. sea surface temperature (SST)). The past decade has seen the development of a new temperature proxy, clumped isotope thermometry, that does not suffer from the same limitations as other methods. ELMO will generate the first clumped isotope-based low-latitude records of SST and hydroclimate across the Cenozoic, including warm intervals that serve as analogues for future climate, from fossil carbonate shells (foraminifera). The novel analytical approach combining low (clumped isotopes)- and high-resolution (in-situ trace element analysis) methods will yield temperature reconstructions on a range of timescales relevant for assessing the different aspects of low-latitude and global climate evolution. ELMO will also, through comparison, provide new insights on methods of climate reconstruction applied thus far and lead to a more reliable picture of past climate in the low-latitudes.