Geological Weather Station-past weather events documented in daily growth bands of marine Giant Clam shells (Tridacna spp.)

Paleoclimate research has built a framework for earth's climate changes over the past 65 million years or even longer. However, the knowledge of weather-timescale extreme events (WEEs, also named paleoweather), such as tropical cyclones, cold/hot temperature waves and rainstorms, under different climate regimes is almost a blank because paleoclimatic reconstructions rarely provide the related information with temporal resolution of shorter than monthly or seasonal scale. Here we show that Giant Clam shells (Tridacna spp.) from the western Pacific have clear daily growth bands and several daily to hourly resolution biological and geochemical records, including daily growth rate, elements/Ca ratios and fluorescence intensity, can be obtained by the Laser Scanning Confocal Microscope (LSCM) and NanoSIMS. The pulsed changes in these ultra-high-resolution proxy records clearly recorded the activities of past WEEs, such as the TCs, marine phytoplankton bloom events, cold surges, and more. Our results open a new window to study the past WEEs using natural paleo-archives and demonstrate that Tridacna paleoweather records could be a useful vehicle for building the relationships between weather and climatic scales in paleoclimate researches. Tridacna are widely distributed in the coral reef systems of the Indo-Pacific tropical oceans. The fossil Tridacna samples under the different climate backgrounds have been proved and could be collected from Indo-Pacific tropical oceans from at least the Miocene. When the Tridacna shells can record the past daily to hourly resolution weather/climate changes, they can be built as Geological Weather Station (GWS) in the tropical areas and we can further investigate the WEEs variations in various climate backgrounds, especially in the past warm and warming periods, which could help us to understand the dynamics of the WEEs and predict their future trends.