Sea salt aerosol deposition in stalagmites

In this project, we evaluate whether the abundance of marine-derived salts in stalagmites from coastal regions can be used to estimate past changes in marine aerosol deposition, which in turn reflects wind intensity and changes in the strength and position of the westerly wind belt. Marine salts are transported inland to the catchment area of coastal caves by strong winds, dissolve in rainfall and infiltrate into caves, and the project will evaluate if they are subsequently incorporated into stalagmites in proportion to aerosol delivery. If confirmed, this new indicator would be applied in this project to produce the first direct records of past aerosol deposition and wind in this region on timescales from the last 300 to last 300,000 years. The indicator could later be applied globally in caves on coastal margins. Such records would resolve several key questions regarding the response of the climate system to orbital and solar forcing and the propagation of climate feedbacks from the North Atlantic to other regions.