Abstract
The North Atlantic experiences basin‐wide, multidecadal changes in sea surface temperature (SST), and this SST variability is linked with regional‐to‐continental scale impacts. These impacts often serve as motivation to study the underlying contributors to Atlantic Multidecadal Variability (AMV). However, these impacts can be more than motivation—they can be tools to study the AMV itself. Herein, we consider the positive correlation between Florida summertime rainfall and the AMV (Enfield et al., 2001, https://doi.org/10.1029/2000GL012745). First, we show that this relationship is apparent in updated observational data sets. Next, we demonstrate that large ensembles of climate models are capable of producing the observed relationship between the AMV and Florida summertime rainfall. Finally, using large ensembles from multiple climate models, we show that historical forcing makes models more likely to capture the observed relationship in summer precipitation. Our findings have implications for our understanding of the AMV and for precipitation projections in at‐risk South Florida.
Plain Language Summary
Ocean temperatures in the North Atlantic fluctuate from decade to decade. When the waters are warmer than average, we show that Florida gets more rain in late summer—at the same time as the region's highest high tides. Planning for the impacts of climate change on Florida requires that we understand the relationship between the temperature of the Atlantic Ocean and Florida precipitation. We show that changes in atmospheric composition (e.g., from greenhouse gases, pollution from industry, and ash and gases from volcanoes) make this connection more likely. So long as Atlantic Ocean temperatures continue to rise, we expect wetter late summer months in Florida in the future.
Key Points
We find an observed in‐phase relationship between multidecadal North Atlantic SST variability and Florida summertime rainfall
In climate models, runs with historical forcing are more likely to produce the observed relationship than control runs
We add evidence that external forcing plays a meaningful role in the AMV with implications for future rainfall during Florida's flood season
