Long instrumental records are crucial for investigating mechanisms of climate variability, for comparing with paleo-proxy datasets, and for contextualizing present-day climate changes. They are especially valuable for understanding the hydrological cycle, where the noisiness of time series can complicate the separation of external forcing signals from internally-generated variability.

In this talk I will discuss research on hydroclimate variability around the tropical and subtropical Atlantic Basin using (mainly) instrumental time series over the past few centuries. I will present work examining recently-digitized precipitation stations from former German colonies in Togo and Cameroon, historical African and South American river discharge, and gridded Atlantic sea surface salinity going back to the early-20th century. I will also discuss investigation back to the 18th century using the record of Nile flood level known as the Nilometer and the recently-developed ModE-RA paleo-reanalysis from the University of Bern, which incorporates disparate instrumental and non-instrumental source data.

Examining these datasets can shed light on processes of hydroclimate variability such as the African monsoon response to volcanic eruptions (particularly the high-latitude eruptions of Laki in 1783 and Katmai in 1912) and meridional shifts of the intertropical convergence zone (ITCZ). I will also discuss some of the interdisciplinary historical and social science questions related to this work.

Lieu
LOCEAN-IPSL, couloir 45-55, 4^e étage, pièce 417

Visio
https://ird-fr.zoom.us/j/92533318933?pwd=E9XKPA5J319gwAOVtN1jt0403rSjas.1